1
0
Fork 0
Commit Graph

1315 Commits (e86283071fb0eed28136adb52997888f4beb202b)

Author SHA1 Message Date
Vegard Nossum f1f1007644 mm: add new mmgrab() helper
Apart from adding the helper function itself, the rest of the kernel is
converted mechanically using:

  git grep -l 'atomic_inc.*mm_count' | xargs sed -i 's/atomic_inc(&\(.*\)->mm_count);/mmgrab\(\1\);/'
  git grep -l 'atomic_inc.*mm_count' | xargs sed -i 's/atomic_inc(&\(.*\)\.mm_count);/mmgrab\(\&\1\);/'

This is needed for a later patch that hooks into the helper, but might
be a worthwhile cleanup on its own.

(Michal Hocko provided most of the kerneldoc comment.)

Link: http://lkml.kernel.org/r/20161218123229.22952-1-vegard.nossum@oracle.com
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-27 18:43:48 -08:00
Dave Jiang 11bac80004 mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf
->fault(), ->page_mkwrite(), and ->pfn_mkwrite() calls do not need to
take a vma and vmf parameter when the vma already resides in vmf.

Remove the vma parameter to simplify things.

[arnd@arndb.de: fix ARM build]
  Link: http://lkml.kernel.org/r/20170125223558.1451224-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/148521301778.19116.10840599906674778980.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:54 -08:00
Markus Elfring 843574a3ed KVM: Return an error code only as a constant in kvm_get_dirty_log()
* Return an error code without storing it in an intermediate variable.

* Delete the local variable "r" and the jump label "out" which became
  unnecessary with this refactoring.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-02-17 12:30:14 +01:00
Markus Elfring 58d6db3491 KVM: Return an error code only as a constant in kvm_get_dirty_log_protect()
* Return an error code without storing it in an intermediate variable.

* Delete the local variable "r" and the jump label "out" which became
  unnecessary with this refactoring.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-02-17 12:30:06 +01:00
Markus Elfring f6a3b168e5 KVM: Return directly after a failed copy_from_user() in kvm_vm_compat_ioctl()
* Return directly after a call of the function "copy_from_user" failed
  in a case block.

  This issue was detected by using the Coccinelle software.

* Delete the jump label "out" which became unnecessary with
  this refactoring.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-02-17 12:29:42 +01:00
Cao, Lei bbd6411513 KVM: Support vCPU-based gfn->hva cache
Provide versions of struct gfn_to_hva_cache functions that
take vcpu as a parameter instead of struct kvm.  The existing functions
are not needed anymore, so delete them.  This allows dirty pages to
be logged in the vcpu dirty ring, instead of the global dirty ring,
for ring-based dirty memory tracking.

Signed-off-by: Lei Cao <lei.cao@stratus.com>
Message-Id: <CY1PR08MB19929BD2AC47A291FD680E83F04F0@CY1PR08MB1992.namprd08.prod.outlook.com>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-02-16 18:42:46 +01:00
Paolo Bonzini 4bd518f159 KVM: use separate generations for each address space
This will make it easier to support multiple address spaces in
kvm_gfn_to_hva_cache_init.  Instead of having to check the address
space id, we can keep on checking just the generation number.

Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-02-16 18:42:41 +01:00
Paolo Bonzini 5a2d4365d2 KVM: only retrieve memslots once when initializing cache
This will make it a bit simpler to handle multiple address spaces
in gfn_to_hva_cache.

Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-02-16 18:42:33 +01:00
Jintack Lim 7b6b46311a KVM: arm/arm64: Emulate the EL1 phys timer registers
Emulate read and write operations to CNTP_TVAL, CNTP_CVAL and CNTP_CTL.
Now VMs are able to use the EL1 physical timer.

Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-08 15:13:37 +00:00
Jintack Lim f242adaf0c KVM: arm/arm64: Set up a background timer for the physical timer emulation
Set a background timer for the EL1 physical timer emulation while VMs
are running, so that VMs get the physical timer interrupts in a timely
manner.

Schedule the background timer on entry to the VM and cancel it on exit.
This would not have any performance impact to the guest OSes that
currently use the virtual timer since the physical timer is always not
enabled.

Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-08 15:13:36 +00:00
Jintack Lim fb280e9757 KVM: arm/arm64: Set a background timer to the earliest timer expiration
When scheduling a background timer, consider both of the virtual and
physical timer and pick the earliest expiration time.

Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-08 15:13:35 +00:00
Jintack Lim 58e0c9732a KVM: arm/arm64: Update the physical timer interrupt level
Now that we maintain the EL1 physical timer register states of VMs,
update the physical timer interrupt level along with the virtual one.

Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-08 15:13:35 +00:00
Jintack Lim a91d18551e KVM: arm/arm64: Initialize the emulated EL1 physical timer
Initialize the emulated EL1 physical timer with the default irq number.

Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-08 15:13:34 +00:00
Jintack Lim 9171fa2e09 KVM: arm/arm64: Decouple kvm timer functions from virtual timer
Now that we have a separate structure for timer context, make functions
generic so that they can work with any timer context, not just the
virtual timer context.  This does not change the virtual timer
functionality.

Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-08 15:13:33 +00:00
Jintack Lim 90de943a43 KVM: arm/arm64: Move cntvoff to each timer context
Make cntvoff per each timer context. This is helpful to abstract kvm
timer functions to work with timer context without considering timer
types (e.g. physical timer or virtual timer).

This also would pave the way for ever doing adjustments of the cntvoff
on a per-CPU basis if that should ever make sense.

Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-08 15:13:33 +00:00
Jintack Lim fbb4aeec5f KVM: arm/arm64: Abstract virtual timer context into separate structure
Abstract virtual timer context into a separate structure and change all
callers referring to timer registers, irq state and so on. No change in
functionality.

This is about to become very handy when adding the EL1 physical timer.

Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-08 15:13:32 +00:00
Shanker Donthineni 0bdbf3b071 KVM: arm/arm64: vgic: Stop injecting the MSI occurrence twice
The IRQFD framework calls the architecture dependent function
twice if the corresponding GSI type is edge triggered. For ARM,
the function kvm_set_msi() is getting called twice whenever the
IRQFD receives the event signal. The rest of the code path is
trying to inject the MSI without any validation checks. No need
to call the function vgic_its_inject_msi() second time to avoid
an unnecessary overhead in IRQ queue logic. It also avoids the
possibility of VM seeing the MSI twice.

Simple fix, return -1 if the argument 'level' value is zero.

Cc: stable@vger.kernel.org
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-08 15:13:14 +00:00
Christoffer Dall 11710dec8a KVM: arm/arm64: Remove kvm_vgic_inject_mapped_irq
The only benefit of having kvm_vgic_inject_mapped_irq separate from
kvm_vgic_inject_irq is that we pass a boolean that we use for error
checking on the injection path.

While this could potentially help in some aspect of robustness, it's
also a little bit of a defensive move, and arguably callers into the
vgic should have make sure they have marked their virtual IRQs as mapped
if required.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-02-01 11:56:35 +01:00
Vijaya Kumar K e96a006cb0 KVM: arm/arm64: vgic: Implement KVM_DEV_ARM_VGIC_GRP_LEVEL_INFO ioctl
Userspace requires to store and restore of line_level for
level triggered interrupts using ioctl KVM_DEV_ARM_VGIC_GRP_LEVEL_INFO.

Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@cavium.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-01-30 13:47:29 +00:00
Vijaya Kumar K d017d7b0bd KVM: arm/arm64: vgic: Implement VGICv3 CPU interface access
VGICv3 CPU interface registers are accessed using
KVM_DEV_ARM_VGIC_CPU_SYSREGS ioctl. These registers are accessed
as 64-bit. The cpu MPIDR value is passed along with register id.
It is used to identify the cpu for registers access.

The VM that supports SEIs expect it on destination machine to handle
guest aborts and hence checked for ICC_CTLR_EL1.SEIS compatibility.
Similarly, VM that supports Affinity Level 3 that is required for AArch64
mode, is required to be supported on destination machine. Hence checked
for ICC_CTLR_EL1.A3V compatibility.

The arch/arm64/kvm/vgic-sys-reg-v3.c handles read and write of VGIC
CPU registers for AArch64.

For AArch32 mode, arch/arm/kvm/vgic-v3-coproc.c file is created but
APIs are not implemented.

Updated arch/arm/include/uapi/asm/kvm.h with new definitions
required to compile for AArch32.

The version of VGIC v3 specification is defined here
Documentation/virtual/kvm/devices/arm-vgic-v3.txt

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@cavium.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-01-30 13:47:25 +00:00
Vijaya Kumar K 5fb247d79c KVM: arm/arm64: vgic: Introduce VENG0 and VENG1 fields to vmcr struct
ICC_VMCR_EL2 supports virtual access to ICC_IGRPEN1_EL1.Enable
and ICC_IGRPEN0_EL1.Enable fields. Add grpen0 and grpen1 member
variables to struct vmcr to support read and write of these fields.

Also refactor vgic_set_vmcr and vgic_get_vmcr() code.
Drop ICH_VMCR_CTLR_SHIFT and ICH_VMCR_CTLR_MASK macros and instead
use ICH_VMCR_EOI* and ICH_VMCR_CBPR* macros.

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@cavium.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-01-30 13:47:21 +00:00
Vijaya Kumar K 94574c9488 KVM: arm/arm64: vgic: Add distributor and redistributor access
VGICv3 Distributor and Redistributor registers are accessed using
KVM_DEV_ARM_VGIC_GRP_DIST_REGS and KVM_DEV_ARM_VGIC_GRP_REDIST_REGS
with KVM_SET_DEVICE_ATTR and KVM_GET_DEVICE_ATTR ioctls.
These registers are accessed as 32-bit and cpu mpidr
value passed along with register offset is used to identify the
cpu for redistributor registers access.

The version of VGIC v3 specification is defined here
Documentation/virtual/kvm/devices/arm-vgic-v3.txt

Also update arch/arm/include/uapi/asm/kvm.h to compile for
AArch32 mode.

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@cavium.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-01-30 13:47:07 +00:00
Vijaya Kumar K 2df903a89a KVM: arm/arm64: vgic: Implement support for userspace access
Read and write of some registers like ISPENDR and ICPENDR
from userspace requires special handling when compared to
guest access for these registers.

Refer to Documentation/virtual/kvm/devices/arm-vgic-v3.txt
for handling of ISPENDR, ICPENDR registers handling.

Add infrastructure to support guest and userspace read
and write for the required registers
Also moved vgic_uaccess from vgic-mmio-v2.c to vgic-mmio.c

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@cavium.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-01-30 13:47:02 +00:00
Christoffer Dall 10f92c4c53 KVM: arm/arm64: vgic: Add debugfs vgic-state file
Add a file to debugfs to read the in-kernel state of the vgic.  We don't
do any locking of the entire VGIC state while traversing all the IRQs,
so if the VM is running the user/developer may not see a quiesced state,
but should take care to pause the VM using facilities in user space for
that purpose.

We also don't support LPIs yet, but they can be added easily if needed.

Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-01-25 13:50:03 +01:00
Christoffer Dall 8694e4da66 KVM: arm/arm64: Remove struct vgic_irq pending field
One of the goals behind the VGIC redesign was to get rid of cached or
intermediate state in the data structures, but we decided to allow
ourselves to precompute the pending value of an IRQ based on the line
level and pending latch state.  However, this has now become difficult
to base proper GICv3 save/restore on, because there is a potential to
modify the pending state without knowing if an interrupt is edge or
level configured.

See the following post and related message for more background:
https://lists.cs.columbia.edu/pipermail/kvmarm/2017-January/023195.html

This commit gets rid of the precomputed pending field in favor of a
function that calculates the value when needed, irq_is_pending().

The soft_pending field is renamed to pending_latch to represent that
this latch is the equivalent hardware latch which gets manipulated by
the input signal for edge-triggered interrupts and when writing to the
SPENDR/CPENDR registers.

After this commit save/restore code should be able to simply restore the
pending_latch state, line_level state, and config state in any order and
get the desired result.

Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-01-25 13:26:13 +01:00
Radim Krčmář 1b1973ef9a KVM/ARM updates for 4.10-rc4
- Fix for timer setup on VHE machines
 - Drop spurious warning when the timer races against
   the vcpu running again
 - Prevent a vgic deadlock when the initialization fails
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJYeLkqAAoJECPQ0LrRPXpDpasP/iynAP2/28LNQ7L8r3be0m7N
 PCZv3gpsTtu1cmTlpiPQVPqzBUVPXQMJJAnDIhA7e1YbYfYJUIhEirVUQ56oT+lY
 nmnoquzNFGUNkYRHUj8RTeQ8ISuP/iPlWOVlSh4n2rbrHFAxX1+W1xXdOedbdFJp
 oFDRR6DCB4qdIxt7dtTcfObhwVlro8WDOfClNqiUDUdhxfDBD7mEPYNO2J2D0/ca
 6YQAkxPzP/MJgKl0mVRjjxhkoNSt6lP0uyU65X67g7i2ZlFRyU3PvqwPm3JOY++V
 Uuff2ud81D5yYwf0+6sA+i+707jezgsoiuFnwUFQVjW/9rpIK7W1gzqht2VWZNgJ
 NjhFPtNhOFkam/sxPFiSaTNyhUNgrg6C/qPDBF0pPlyGd0mtrvJdVG4y/R9YGSB3
 JoiwaFdoi9buEakpRbhu4y5bhcDZZPAo+l+2OanpeE6y3zypqTsJRop8H/qhnv8R
 FFzqycBjeEcVo9ZKIpqQVEnp0njBcHKmqblMswgSgGKe3816iGC+kj4oMm7J57Yq
 vy1OKQMuur+rSRyH7LpVN1HYiq9yBHdbHsXxUjEWSD5dtPAGdOhAP0kAzXlPbEot
 WkVQO2uEV3EKs0UQjWkLKNVJKh/pPaWH3z8ENRlf+pASzvO+UYRmY3sjfDcg3AsI
 7Lxc+CVJJ4ExJbFe/OTk
 =7cIH
 -----END PGP SIGNATURE-----

Merge tag 'kvm-arm-for-4.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm

KVM/ARM updates for 4.10-rc4

- Fix for timer setup on VHE machines
- Drop spurious warning when the timer races against
  the vcpu running again
- Prevent a vgic deadlock when the initialization fails
2017-01-17 15:04:59 +01:00
Marc Zyngier 1193e6aeec KVM: arm/arm64: vgic: Fix deadlock on error handling
Dmitry Vyukov reported that the syzkaller fuzzer triggered a
deadlock in the vgic setup code when an error was detected, as
the cleanup code tries to take a lock that is already held by
the setup code.

The fix is to avoid retaking the lock when cleaning up, by
telling the cleanup function that we already hold it.

Cc: stable@vger.kernel.org
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-01-13 11:19:35 +00:00
Jintack Lim 488f94d721 KVM: arm64: Access CNTHCTL_EL2 bit fields correctly on VHE systems
Current KVM world switch code is unintentionally setting wrong bits to
CNTHCTL_EL2 when E2H == 1, which may allow guest OS to access physical
timer.  Bit positions of CNTHCTL_EL2 are changing depending on
HCR_EL2.E2H bit.  EL1PCEN and EL1PCTEN are 1st and 0th bits when E2H is
not set, but they are 11th and 10th bits respectively when E2H is set.

In fact, on VHE we only need to set those bits once, not for every world
switch. This is because the host kernel runs in EL2 with HCR_EL2.TGE ==
1, which makes those bits have no effect for the host kernel execution.
So we just set those bits once for guests, and that's it.

Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-01-13 11:19:25 +00:00
Christoffer Dall 63e41226af KVM: arm/arm64: Fix occasional warning from the timer work function
When a VCPU blocks (WFI) and has programmed the vtimer, we program a
soft timer to expire in the future to wake up the vcpu thread when
appropriate.  Because such as wake up involves a vcpu kick, and the
timer expire function can get called from interrupt context, and the
kick may sleep, we have to schedule the kick in the work function.

The work function currently has a warning that gets raised if it turns
out that the timer shouldn't fire when it's run, which was added because
the idea was that in that case the work should never have been cancelled.

However, it turns out that this whole thing is racy and we can get
spurious warnings.  The problem is that we clear the armed flag in the
work function, which may run in parallel with the
kvm_timer_unschedule->timer_disarm() call.  This results in a possible
situation where the timer_disarm() call does not call
cancel_work_sync(), which effectively synchronizes the completion of the
work function with running the VCPU.  As a result, the VCPU thread
proceeds before the work function completees, causing changes to the
timer state such that kvm_timer_should_fire(vcpu) returns false in the
work function.

All we do in the work function is to kick the VCPU, and an occasional
rare extra kick never harmed anyone.  Since the race above is extremely
rare, we don't bother checking if the race happens but simply remove the
check and the clearing of the armed flag from the work function.

Reported-by: Matthias Brugger <mbrugger@suse.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-01-13 11:15:30 +00:00
Wanpeng Li 4f3dbdf47e KVM: eventfd: fix NULL deref irqbypass consumer
Reported syzkaller:

    BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
    IP: irq_bypass_unregister_consumer+0x9d/0xb70 [irqbypass]
    PGD 0

    Oops: 0002 [#1] SMP
    CPU: 1 PID: 125 Comm: kworker/1:1 Not tainted 4.9.0+ #1
    Workqueue: kvm-irqfd-cleanup irqfd_shutdown [kvm]
    task: ffff9bbe0dfbb900 task.stack: ffffb61802014000
    RIP: 0010:irq_bypass_unregister_consumer+0x9d/0xb70 [irqbypass]
    Call Trace:
     irqfd_shutdown+0x66/0xa0 [kvm]
     process_one_work+0x16b/0x480
     worker_thread+0x4b/0x500
     kthread+0x101/0x140
     ? process_one_work+0x480/0x480
     ? kthread_create_on_node+0x60/0x60
     ret_from_fork+0x25/0x30
    RIP: irq_bypass_unregister_consumer+0x9d/0xb70 [irqbypass] RSP: ffffb61802017e20
    CR2: 0000000000000008

The syzkaller folks reported a NULL pointer dereference that due to
unregister an consumer which fails registration before. The syzkaller
creates two VMs w/ an equal eventfd occasionally. So the second VM
fails to register an irqbypass consumer. It will make irqfd as inactive
and queue an workqueue work to shutdown irqfd and unregister the irqbypass
consumer when eventfd is closed. However, the second consumer has been
initialized though it fails registration. So the token(same as the first
VM's) is taken to unregister the consumer through the workqueue, the
consumer of the first VM is found and unregistered, then NULL deref incurred
in the path of deleting consumer from the consumers list.

This patch fixes it by making irq_bypass_register/unregister_consumer()
looks for the consumer entry based on consumer pointer itself instead of
token matching.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Suggested-by: Alex Williamson <alex.williamson@redhat.com>
Cc: stable@vger.kernel.org
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-01-12 14:42:34 +01:00
Linus Torvalds 3ddc76dfc7 Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer type cleanups from Thomas Gleixner:
 "This series does a tree wide cleanup of types related to
  timers/timekeeping.

   - Get rid of cycles_t and use a plain u64. The type is not really
     helpful and caused more confusion than clarity

   - Get rid of the ktime union. The union has become useless as we use
     the scalar nanoseconds storage unconditionally now. The 32bit
     timespec alike storage got removed due to the Y2038 limitations
     some time ago.

     That leaves the odd union access around for no reason. Clean it up.

  Both changes have been done with coccinelle and a small amount of
  manual mopping up"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ktime: Get rid of ktime_equal()
  ktime: Cleanup ktime_set() usage
  ktime: Get rid of the union
  clocksource: Use a plain u64 instead of cycle_t
2016-12-25 14:30:04 -08:00
Linus Torvalds b272f732f8 Merge branch 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull SMP hotplug notifier removal from Thomas Gleixner:
 "This is the final cleanup of the hotplug notifier infrastructure. The
  series has been reintgrated in the last two days because there came a
  new driver using the old infrastructure via the SCSI tree.

  Summary:

   - convert the last leftover drivers utilizing notifiers

   - fixup for a completely broken hotplug user

   - prevent setup of already used states

   - removal of the notifiers

   - treewide cleanup of hotplug state names

   - consolidation of state space

  There is a sphinx based documentation pending, but that needs review
  from the documentation folks"

* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/armada-xp: Consolidate hotplug state space
  irqchip/gic: Consolidate hotplug state space
  coresight/etm3/4x: Consolidate hotplug state space
  cpu/hotplug: Cleanup state names
  cpu/hotplug: Remove obsolete cpu hotplug register/unregister functions
  staging/lustre/libcfs: Convert to hotplug state machine
  scsi/bnx2i: Convert to hotplug state machine
  scsi/bnx2fc: Convert to hotplug state machine
  cpu/hotplug: Prevent overwriting of callbacks
  x86/msr: Remove bogus cleanup from the error path
  bus: arm-ccn: Prevent hotplug callback leak
  perf/x86/intel/cstate: Prevent hotplug callback leak
  ARM/imx/mmcd: Fix broken cpu hotplug handling
  scsi: qedi: Convert to hotplug state machine
2016-12-25 14:05:56 -08:00
Thomas Gleixner a5a1d1c291 clocksource: Use a plain u64 instead of cycle_t
There is no point in having an extra type for extra confusion. u64 is
unambiguous.

Conversion was done with the following coccinelle script:

@rem@
@@
-typedef u64 cycle_t;

@fix@
typedef cycle_t;
@@
-cycle_t
+u64

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
2016-12-25 11:04:12 +01:00
Thomas Gleixner 73c1b41e63 cpu/hotplug: Cleanup state names
When the state names got added a script was used to add the extra argument
to the calls. The script basically converted the state constant to a
string, but the cleanup to convert these strings into meaningful ones did
not happen.

Replace all the useless strings with 'subsys/xxx/yyy:state' strings which
are used in all the other places already.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Link: http://lkml.kernel.org/r/20161221192112.085444152@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-25 10:47:44 +01:00
Linus Torvalds 7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Lorenzo Stoakes 8b7457ef9a mm: unexport __get_user_pages_unlocked()
Unexport the low-level __get_user_pages_unlocked() function and replaces
invocations with calls to more appropriate higher-level functions.

In hva_to_pfn_slow() we are able to replace __get_user_pages_unlocked()
with get_user_pages_unlocked() since we can now pass gup_flags.

In async_pf_execute() and process_vm_rw_single_vec() we need to pass
different tsk, mm arguments so get_user_pages_remote() is the sane
replacement in these cases (having added manual acquisition and release
of mmap_sem.)

Additionally get_user_pages_remote() reintroduces use of the FOLL_TOUCH
flag.  However, this flag was originally silently dropped by commit
1e9877902d ("mm/gup: Introduce get_user_pages_remote()"), so this
appears to have been unintentional and reintroducing it is therefore not
an issue.

[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/20161027095141.2569-3-lstoakes@gmail.com
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-14 16:04:09 -08:00
Linus Torvalds 93173b5bf2 Small release, the most interesting stuff is x86 nested virt improvements.
x86: userspace can now hide nested VMX features from guests; nested
 VMX can now run Hyper-V in a guest; support for AVX512_4VNNIW and
 AVX512_FMAPS in KVM; infrastructure support for virtual Intel GPUs.
 
 PPC: support for KVM guests on POWER9; improved support for interrupt
 polling; optimizations and cleanups.
 
 s390: two small optimizations, more stuff is in flight and will be
 in 4.11.
 
 ARM: support for the GICv3 ITS on 32bit platforms.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQExBAABCAAbBQJYTkP0FBxwYm9uemluaUByZWRoYXQuY29tAAoJEL/70l94x66D
 lZIH/iT1n9OQXcuTpYYnQhuCenzI3GZZOIMTbCvK2i5bo0FIJKxVn0EiAAqZSXvO
 nO185FqjOgLuJ1AD1kJuxzye5suuQp4HIPWWgNHcexLuy43WXWKZe0IQlJ4zM2Xf
 u31HakpFmVDD+Cd1qN3yDXtDrRQ79/xQn2kw7CWb8olp+pVqwbceN3IVie9QYU+3
 gCz0qU6As0aQIwq2PyalOe03sO10PZlm4XhsoXgWPG7P18BMRhNLTDqhLhu7A/ry
 qElVMANT7LSNLzlwNdpzdK8rVuKxETwjlc1UP8vSuhrwad4zM2JJ1Exk26nC2NaG
 D0j4tRSyGFIdx6lukZm7HmiSHZ0=
 =mkoB
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "Small release, the most interesting stuff is x86 nested virt
  improvements.

  x86:
   - userspace can now hide nested VMX features from guests
   - nested VMX can now run Hyper-V in a guest
   - support for AVX512_4VNNIW and AVX512_FMAPS in KVM
   - infrastructure support for virtual Intel GPUs.

  PPC:
   - support for KVM guests on POWER9
   - improved support for interrupt polling
   - optimizations and cleanups.

  s390:
   - two small optimizations, more stuff is in flight and will be in
     4.11.

  ARM:
   - support for the GICv3 ITS on 32bit platforms"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (94 commits)
  arm64: KVM: pmu: Reset PMSELR_EL0.SEL to a sane value before entering the guest
  KVM: arm/arm64: timer: Check for properly initialized timer on init
  KVM: arm/arm64: vgic-v2: Limit ITARGETSR bits to number of VCPUs
  KVM: x86: Handle the kthread worker using the new API
  KVM: nVMX: invvpid handling improvements
  KVM: nVMX: check host CR3 on vmentry and vmexit
  KVM: nVMX: introduce nested_vmx_load_cr3 and call it on vmentry
  KVM: nVMX: propagate errors from prepare_vmcs02
  KVM: nVMX: fix CR3 load if L2 uses PAE paging and EPT
  KVM: nVMX: load GUEST_EFER after GUEST_CR0 during emulated VM-entry
  KVM: nVMX: generate MSR_IA32_CR{0,4}_FIXED1 from guest CPUID
  KVM: nVMX: fix checks on CR{0,4} during virtual VMX operation
  KVM: nVMX: support restore of VMX capability MSRs
  KVM: nVMX: generate non-true VMX MSRs based on true versions
  KVM: x86: Do not clear RFLAGS.TF when a singlestep trap occurs.
  KVM: x86: Add kvm_skip_emulated_instruction and use it.
  KVM: VMX: Move skip_emulated_instruction out of nested_vmx_check_vmcs12
  KVM: VMX: Reorder some skip_emulated_instruction calls
  KVM: x86: Add a return value to kvm_emulate_cpuid
  KVM: PPC: Book3S: Move prototypes for KVM functions into kvm_ppc.h
  ...
2016-12-13 15:47:02 -08:00
Linus Torvalds edc5f445a6 VFIO updates for v4.10-rc1
- VFIO updates for v4.10 primarily include a new Mediated Device
    interface, which essentially allows software defined devices to be
    exposed to users through VFIO.  The host vendor driver providing
    this virtual device polices, or mediates user access to the device.
    These devices often incorporate portions of real devices, for
    instance the primary initial users of this interface expose vGPUs
    which allow the user to map mediated devices, or mdevs, to a
    portion of a physical GPU.  QEMU composes these mdevs into PCI
    representations using the existing VFIO user API.  This enables
    both Intel KVM-GT support, which is also expected to arrive into
    Linux mainline during the v4.10 merge window, as well as NVIDIA
    vGPU, and also Channel I/O devices (aka CCW devices) for s390
    virtualization support. (Kirti Wankhede, Neo Jia)
 
  - Drop unnecessary uses of pcibios_err_to_errno() (Cao Jin)
 
  - Fixes to VFIO capability chain handling (Eric Auger)
 
  - Error handling fixes for fallout from mdev (Christophe JAILLET)
 
  - Notifiers to expose struct kvm to mdev vendor drivers (Jike Song)
 
  - type1 IOMMU model search fixes (Kirti Wankhede, Neo Jia)
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.14 (GNU/Linux)
 
 iQIcBAABAgAGBQJYSyCtAAoJECObm247sIsi+rIP/3Q/GE3zaDdz1iKQK/c/qhs6
 0Pl45opAqw4wCJDCZIhRmoHmsCaT4KkeJKU1fiYc0mKJhW11HfA4DTFwzBqrHBj7
 7wPjHTaWwlFRHCYVCWYEp5g9UASyD8ubWGyZKzqIXELFoAvwuBL3SULNj4neJKKR
 rPcHTVxJ7laYIjHFzuNUi/MWEdjxPT9oJn8Bm9mhISwPglIMU9nkIR20ChaSeFJb
 MiFqFW7BcvkVyqupjpksM9DodpNZu+3uSMVtgASNVNbilf0FXJr0d8RCbeSxTIfm
 rEsZ5+0PrklhCtmRRl5EB+tNawgaism8wAF74KIO//76vE02Usrxb0b5mTIZ8TiN
 6/Z+WID5D+ZRt8hp9hJIJmGE/sM/odH4r174dPaiEkMvOB9ksDIPkzgbtDbVY40c
 DACb7/n3ZZA0an2Eq2HEx/BqTOvt9sgu367KVvhuoIArQcb5SM94GT03Dv+pKnax
 Cxmro2oaWmAV3IS0vNzbCIddsFqlPjkFIYxjtzBy+bVLg2RN3STyaSL6cwJsydSU
 KLcCPiYtovczKFj7RJlgVlqh5/8uZ7SEffTkIggehdnVPAfDlK9p9BYqLCgAoWpN
 vwWidM3qOIjooRXQgxUwJgJsl4MLRMoA/gFP4iHbqOgIAGtUDRHuQ4muvkf+LLxg
 wpgfXsBQNRuVcZHBUEVe
 =gc6j
 -----END PGP SIGNATURE-----

Merge tag 'vfio-v4.10-rc1' of git://github.com/awilliam/linux-vfio

Pull VFIO updates from Alex Williamson:

 - VFIO updates for v4.10 primarily include a new Mediated Device
   interface, which essentially allows software defined devices to be
   exposed to users through VFIO. The host vendor driver providing this
   virtual device polices, or mediates user access to the device.

   These devices often incorporate portions of real devices, for
   instance the primary initial users of this interface expose vGPUs
   which allow the user to map mediated devices, or mdevs, to a portion
   of a physical GPU. QEMU composes these mdevs into PCI representations
   using the existing VFIO user API. This enables both Intel KVM-GT
   support, which is also expected to arrive into Linux mainline during
   the v4.10 merge window, as well as NVIDIA vGPU, and also Channel I/O
   devices (aka CCW devices) for s390 virtualization support. (Kirti
   Wankhede, Neo Jia)

 - Drop unnecessary uses of pcibios_err_to_errno() (Cao Jin)

 - Fixes to VFIO capability chain handling (Eric Auger)

 - Error handling fixes for fallout from mdev (Christophe JAILLET)

 - Notifiers to expose struct kvm to mdev vendor drivers (Jike Song)

 - type1 IOMMU model search fixes (Kirti Wankhede, Neo Jia)

* tag 'vfio-v4.10-rc1' of git://github.com/awilliam/linux-vfio: (30 commits)
  vfio iommu type1: Fix size argument to vfio_find_dma() in pin_pages/unpin_pages
  vfio iommu type1: Fix size argument to vfio_find_dma() during DMA UNMAP.
  vfio iommu type1: WARN_ON if notifier block is not unregistered
  kvm: set/clear kvm to/from vfio_group when group add/delete
  vfio: support notifier chain in vfio_group
  vfio: vfio_register_notifier: classify iommu notifier
  vfio: Fix handling of error returned by 'vfio_group_get_from_dev()'
  vfio: fix vfio_info_cap_add/shift
  vfio/pci: Drop unnecessary pcibios_err_to_errno()
  MAINTAINERS: Add entry VFIO based Mediated device drivers
  docs: Sample driver to demonstrate how to use Mediated device framework.
  docs: Sysfs ABI for mediated device framework
  docs: Add Documentation for Mediated devices
  vfio: Define device_api strings
  vfio_platform: Updated to use vfio_set_irqs_validate_and_prepare()
  vfio_pci: Updated to use vfio_set_irqs_validate_and_prepare()
  vfio: Introduce vfio_set_irqs_validate_and_prepare()
  vfio_pci: Update vfio_pci to use vfio_info_add_capability()
  vfio: Introduce common function to add capabilities
  vfio iommu: Add blocking notifier to notify DMA_UNMAP
  ...
2016-12-13 09:23:56 -08:00
Paolo Bonzini f673b5b2a6 KVM/ARM updates for 4.10:
- Support for the GICv3 ITS on 32bit platforms
 - A handful of timer and GIC emulation fixes
 - A PMU architecture fix
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJYStI0AAoJECPQ0LrRPXpD6kcP/0J+fynLo/uhe3VAP7pZ0fH5
 dFmvcgZaHQ6wpWgkHYbyuAkZ2tiQfthylErjt9Xay2qf3f0BZScsNKSkTOmVTOJH
 NO+4yo7YDIbRbQO3h+QX2YB3uBqdZvn6eRLCDWNLwSa/GkNmLGvhcorQer0GduCl
 qnsRRrNIewzSYI+U3821jVUjLgXuBuGoFt0yT/197ZBRIrowNJ4vqAvaqVaLQ4jt
 aOd+aCPKCaatkeewEo6Es4lX86JOytpxtVfNpRe6/gSr1mK2fHAfycQ5Txkl7oTX
 T/vsYUusYDSJbiz7PUMFBfNYvVijBY8QCtm6yJZHQNg6q25r3pjn//3BiuSDf4Dz
 o0DDMoFPjEi23myfGI91oeL9Svbtk06ERGyN7MY2vMNtORrwhmgNiSfIsqI9V0d8
 Slru3REMZg+ZbY6rgyJZa9/09vlwKfqZpkwJlfQkJO9tsXn4WwwdyvwIXmaH9p5X
 mqnjgbIMRipBs5Teedb++pC5XQcbC8ed2KMEBXlgORDm6fC0Pz/q623tVRYhIm4B
 4YKHI1A8I8XaYd0VJkZOns2Uq7/Uwc2j5wGWRIa0IwB6LXlzNw4kbD+omj0Mmo0V
 Fxio610jyTfrPidx/XzO0zsEzVW794Si8S4F1nFShdkk1NuzClVnQzce5TA8K3Zu
 cCUKISR4oi5IWVcimDQt
 =zxXl
 -----END PGP SIGNATURE-----

Merge tag 'kvm-arm-for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/ARM updates for 4.10:

- Support for the GICv3 ITS on 32bit platforms
- A handful of timer and GIC emulation fixes
- A PMU architecture fix
2016-12-12 07:29:39 +01:00
Ingo Molnar 6f38751510 Merge branch 'linus' into locking/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-11 13:07:13 +01:00
Christoffer Dall 8e1a0476f8 KVM: arm/arm64: timer: Check for properly initialized timer on init
When the arch timer code fails to initialize (for example because the
memory mapped timer doesn't work, which is currently seen with the AEM
model), then KVM just continues happily with a final result that KVM
eventually does a NULL pointer dereference of the uninitialized cycle
counter.

Check directly for this in the init path and give the user a reasonable
error in this case.

Cc: Shih-Wei Li <shihwei@cs.columbia.edu>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-12-09 15:47:00 +00:00
Andre Przywara 266068eabb KVM: arm/arm64: vgic-v2: Limit ITARGETSR bits to number of VCPUs
The GICv2 spec says in section 4.3.12 that a "CPU targets field bit that
corresponds to an unimplemented CPU interface is RAZ/WI."
Currently we allow the guest to write any value in there and it can
read that back.
Mask the written value with the proper CPU mask to be spec compliant.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-12-09 15:46:59 +00:00
Jike Song 2fc1bec158 kvm: set/clear kvm to/from vfio_group when group add/delete
Sometimes users need to be aware when a vfio_group attaches to a
KVM or detaches from it. KVM already calls get/put method from vfio to
manipulate the vfio_group reference, it can notify vfio_group in
a similar way.

Cc: Kirti Wankhede <kwankhede@nvidia.com>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Jike Song <jike.song@intel.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-12-01 10:42:17 -07:00
Dan Carpenter a0f1d21c1c KVM: use after free in kvm_ioctl_create_device()
We should move the ops->destroy(dev) after the list_del(&dev->vm_node)
so that we don't use "dev" after freeing it.

Fixes: a28ebea2ad ("KVM: Protect device ops->create and list_add with kvm->lock")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-12-01 16:10:50 +01:00
Radim Krčmář 0f4828a1da KVM/ARM updates for v4.9-rc7
- Do not call kvm_notify_acked for PPIs
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJYNzGYAAoJECPQ0LrRPXpDwC8P/3SlsYK9ickZfxoX05tfwbmy
 H5IVmMvnhqQwi2ALe1PycKU9a9c5MISEvFyzGtr/SVkwZdiGRztGCQsYgxAyL0Tr
 mJDttavNU8B9YKC/d+pNNl18uue1Ny297aPDwL6eo3i9s7MX7EZRdRG3U0MiGlbB
 MFVCOLCAd8eUGI68eE5CsRC5+3OFqbkh2JlgtZJPV1BDu/K1ojViijUnpv/CJX52
 8g8qKU9xTgHnd1pTAaE22u5+odgOvOa62rGqVAF8T9eOMpVHxUDeAvzaFLXQAgty
 tVwYlEtoglLKXFa/B0dqBX639J8hLKBC3gBM/1sEbUU4Ii026iPuCbWLjDGju7Ra
 ggaeFp9X8IK9wcwyT88yUAFLwk/neApm5YemzdD7VWSb/5Np3mJpuIH7McwoJp3p
 cvXrTV4P+XBSYgYSdBsGKSQo38dynW8m8Gqq3D5DEAJc33P/kvwBMFRuzj/F3GwZ
 5w1uTDJx+tTdGhpEvxY+Mwb17XDid9WPKyYdgI5Xy662g904m7WmQvP08VezxVcw
 woMlqqSpJvsNxOphj3xRb00W61MTu7zcfYQlwiDwtEqXgIPlpk3tBZO651eMMaSF
 bQmP2qPDKw5UQHtRfcDq4SmcyvaDn6j9BMYCR/XvXmtlFi7+zyglhkIn+wkJF0Dz
 J/hmZNTPVN6rtRv9wY/2
 =1IXI
 -----END PGP SIGNATURE-----

Merge tag 'kvm-arm-for-4.9-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm

KVM/ARM updates for v4.9-rc7

- Do not call kvm_notify_acked for PPIs
2016-12-01 14:56:34 +01:00
Suraj Jitindar Singh ec76d819d2 KVM: Export kvm module parameter variables
The kvm module has the parameters halt_poll_ns, halt_poll_ns_grow, and
halt_poll_ns_shrink. Halt polling was recently added to the powerpc kvm-hv
module and these parameters were essentially duplicated for that. There is
no benefit to this duplication and it can lead to confusion when trying to
tune halt polling.

Thus move the definition of these variables to kvm_host.h and export them.
This will allow the kvm-hv module to use the same module parameters by
accessing these variables, which will be implemented in the next patch,
meaning that they will no longer be duplicated.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-11-28 11:48:47 +11:00
Marc Zyngier 8ca18eec2b KVM: arm/arm64: vgic: Don't notify EOI for non-SPIs
When we inject a level triggerered interrupt (and unless it
is backed by the physical distributor - timer style), we request
a maintenance interrupt. Part of the processing for that interrupt
is to feed to the rest of KVM (and to the eventfd subsystem) the
information that the interrupt has been EOIed.

But that notification only makes sense for SPIs, and not PPIs
(such as the PMU interrupt). Skip over the notification if
the interrupt is not an SPI.

Cc: stable@vger.kernel.org # 4.7+
Fixes: 140b086dd1 ("KVM: arm/arm64: vgic-new: Add GICv2 world switch backend")
Fixes: 59529f69f5 ("KVM: arm/arm64: vgic-new: Add GICv3 world switch backend")
Reported-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-11-24 13:12:07 +00:00
Pan Xinhui 4ec6e86362 kvm: Introduce kvm_write_guest_offset_cached()
It allows us to update some status or field of a structure partially.

We can also save a kvm_read_guest_cached() call if we just update one
fild of the struct regardless of its current value.

Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: benh@kernel.crashing.org
Cc: boqun.feng@gmail.com
Cc: borntraeger@de.ibm.com
Cc: bsingharora@gmail.com
Cc: dave@stgolabs.net
Cc: jgross@suse.com
Cc: kernellwp@gmail.com
Cc: konrad.wilk@oracle.com
Cc: linuxppc-dev@lists.ozlabs.org
Cc: mpe@ellerman.id.au
Cc: paulmck@linux.vnet.ibm.com
Cc: paulus@samba.org
Cc: rkrcmar@redhat.com
Cc: virtualization@lists.linux-foundation.org
Cc: will.deacon@arm.com
Cc: xen-devel-request@lists.xenproject.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1478077718-37424-8-git-send-email-xinhui.pan@linux.vnet.ibm.com
[ Typo fixes. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-22 12:48:07 +01:00
Paolo Bonzini 22583f0d9c KVM: async_pf: avoid recursive flushing of work items
This was reported by syzkaller:

    [ INFO: possible recursive locking detected ]
    4.9.0-rc4+ #49 Not tainted
    ---------------------------------------------
    kworker/2:1/5658 is trying to acquire lock:
     ([ 1644.769018] (&work->work)
    [<     inline     >] list_empty include/linux/compiler.h:243
    [<ffffffff8128dd60>] flush_work+0x0/0x660 kernel/workqueue.c:1511

    but task is already holding lock:
     ([ 1644.769018] (&work->work)
    [<ffffffff812916ab>] process_one_work+0x94b/0x1900 kernel/workqueue.c:2093

    stack backtrace:
    CPU: 2 PID: 5658 Comm: kworker/2:1 Not tainted 4.9.0-rc4+ #49
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
    Workqueue: events async_pf_execute
     ffff8800676ff630 ffffffff81c2e46b ffffffff8485b930 ffff88006b1fc480
     0000000000000000 ffffffff8485b930 ffff8800676ff7e0 ffffffff81339b27
     ffff8800676ff7e8 0000000000000046 ffff88006b1fcce8 ffff88006b1fccf0
    Call Trace:
    ...
    [<ffffffff8128ddf3>] flush_work+0x93/0x660 kernel/workqueue.c:2846
    [<ffffffff812954ea>] __cancel_work_timer+0x17a/0x410 kernel/workqueue.c:2916
    [<ffffffff81295797>] cancel_work_sync+0x17/0x20 kernel/workqueue.c:2951
    [<ffffffff81073037>] kvm_clear_async_pf_completion_queue+0xd7/0x400 virt/kvm/async_pf.c:126
    [<     inline     >] kvm_free_vcpus arch/x86/kvm/x86.c:7841
    [<ffffffff810b728d>] kvm_arch_destroy_vm+0x23d/0x620 arch/x86/kvm/x86.c:7946
    [<     inline     >] kvm_destroy_vm virt/kvm/kvm_main.c:731
    [<ffffffff8105914e>] kvm_put_kvm+0x40e/0x790 virt/kvm/kvm_main.c:752
    [<ffffffff81072b3d>] async_pf_execute+0x23d/0x4f0 virt/kvm/async_pf.c:111
    [<ffffffff8129175c>] process_one_work+0x9fc/0x1900 kernel/workqueue.c:2096
    [<ffffffff8129274f>] worker_thread+0xef/0x1480 kernel/workqueue.c:2230
    [<ffffffff812a5a94>] kthread+0x244/0x2d0 kernel/kthread.c:209
    [<ffffffff831f102a>] ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:433

The reason is that kvm_put_kvm is causing the destruction of the VM, but
the page fault is still on the ->queue list.  The ->queue list is owned
by the VCPU, not by the work items, so we cannot just add list_del to
the work item.

Instead, use work->vcpu to note async page faults that have been resolved
and will be processed through the done list.  There is no need to flush
those.

Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-11-19 19:04:17 +01:00
Radim Krčmář e5dbc4bf0b KVM/ARM updates for v4.9-rc6
- Fix handling of the 32bit cycle counter
 - Fix cycle counter filtering
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJYLsbzAAoJECPQ0LrRPXpDXdoQAL4tI3HDNKGP71aNNBrCqmOw
 WZFYagsTRgpAePctjxkFZAGHmJoQ/SDOeg6qcb0LKTMQ6ZaorV8+MGWOjvpNtQHz
 ltpdbVUxPCfLzZAUYWyg6PoF5geHrSVHfb+AMShiZePp2/5Rf+9M2MioGz53cDZW
 UmjmvUYi3LF9lwSqdbGJZtpfEOZp4aNeKLQ6I9Cw65NuVjrJzEJ4cRKCk4id9PlW
 jeULDNX5EsnKnyjwROyghCV2RITZ7lpgvQr9PGBleZ0k5kEAqN0pxi9gAWA8D2lC
 uLdBdfFBW9wM31urCFeOMu6S3Ff0v3tquPZK6f2m1Ul+Bii+Kfr5i0U6VfwsvOc6
 TRn6r6FiiQV/OXz3GYqHkd7qEGyIPNv7j5Y3OFZo1uN3v60nnkU32NfalBRDCJE4
 9Q4SvZ3z5oZ12QYYNaCwwR1g3Xd6wuV4JYH+6Z4JFfazJLQ5zgr123iglhmDAneC
 Gurmn1GnkgiwXzMaYCRYKXxX/D+Gob6hRCT9OszqqrpgOzlRIIbZcEKua8T9ihnS
 xDY4+QFwaVsGeWJCjOXPw4wU0l0HUQ+J5u/3DRwv9u0qnW4VBvWCoHHeXxjypqtC
 Lzw04M8ZH98p0zsN4SX7pXjkkRtcTOnwdW7gVyIbq10kT/ylBvrOaFfiXtuIZCQ2
 yD0Qvg/cUs4vWZqhFx2t
 =cJHy
 -----END PGP SIGNATURE-----

Merge tag 'kvm-arm-for-4.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm

KVM/ARM updates for v4.9-rc6

- Fix handling of the 32bit cycle counter
- Fix cycle counter filtering
2016-11-19 18:02:07 +01:00
Wei Huang b112c84a6f KVM: arm64: Fix the issues when guest PMCCFILTR is configured
KVM calls kvm_pmu_set_counter_event_type() when PMCCFILTR is configured.
But this function can't deals with PMCCFILTR correctly because the evtCount
bits of PMCCFILTR, which is reserved 0, conflits with the SW_INCR event
type of other PMXEVTYPER<n> registers. To fix it, when eventsel == 0, this
function shouldn't return immediately; instead it needs to check further
if select_idx is ARMV8_PMU_CYCLE_IDX.

Another issue is that KVM shouldn't copy the eventsel bits of PMCCFILTER
blindly to attr.config. Instead it ought to convert the request to the
"cpu cycle" event type (i.e. 0x11).

To support this patch and to prevent duplicated definitions, a limited
set of ARMv8 perf event types were relocated from perf_event.c to
asm/perf_event.h.

Cc: stable@vger.kernel.org # 4.6+
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Wei Huang <wei@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-11-18 09:06:58 +00:00
Radim Krčmář 813ae37e6a Merge branch 'x86/cpufeature' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into kvm/next
Topic branch for AVX512_4VNNIW and AVX512_4FMAPS support in KVM.
2016-11-16 22:07:36 +01:00
Longpeng(Mike) fd5ebf99f8 arm/arm64: KVM: Clean up useless code in kvm_timer_enable
1) Since commit:41a54482 changed timer enabled variable to per-vcpu,
   the correlative comment in kvm_timer_enable is useless now.

2) After the kvm module init successfully, the timecounter is always
   non-null, so we can remove the checking of timercounter.

Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-11-15 11:54:16 +00:00
Vladimir Murzin 2988509dd8 ARM: KVM: Support vGICv3 ITS
This patch allows to build and use vGICv3 ITS in 32-bit mode.

Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-11-14 10:32:54 +00:00
Vladimir Murzin e29bd6f267 KVM: arm64: vgic-its: Fix compatibility with 32-bit
Evaluate GITS_BASER_ENTRY_SIZE once as an int data (GITS_BASER<n>'s
Entry Size is 5-bit wide only), so when used as divider no reference
to __aeabi_uldivmod is generated when build for AArch32.

Use unsigned long long for GITS_BASER_PAGE_SIZE_* since they are
used in conjunction with 64-bit data.

Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-11-14 10:32:24 +00:00
Paolo Bonzini 05d36a7dff KVM/ARM updates for v4.9-rc4
- Kick the vcpu when a pending interrupt becomes pending again
 - Prevent access to invalid interrupt registers
 - Invalid TLBs when two vcpus from the same VM share a CPU
 -----BEGIN PGP SIGNATURE-----
 
 iQIyBAABCAAcBQJYHNMTFRxtYXJjLnp5bmdpZXJAYXJtLmNvbQAKCRAj0NC60T16
 Q1WDD/9d5KfQ3dWiLtBXbeD3w2K0gXknwLAMsCCAdhgkCdLenxSBjlB7lmVYi1lZ
 pTnshnR4HC0P3yW3bA78J7LZnUzJg72pq/S5K/om9KylVUdXz9WzQ3u+XyB3KTFW
 b+viTUK3mqose67UcBSKGfFEWpIOmJ/nZVvWAIaUTg49btxnetKjyhv2Ux744Hm/
 Jba3trcA4m8RPJ8Vu6mIfd6gkTXzSkQaN2wGVaEFhCFHOPDCQHjcdspe20Ig9fmY
 kTXEBe4r0sC+8fXoymEM6TDQFWB8WthIIqfeIJ3FgfoETKrwmyJ23YfLAh49m1cB
 nFpyy/lr9PNsOjJKXFi84pzx6l8U/CDslnBm5klYTT2kFc3stKbyDtIILvUOwKl8
 n9UZSO8NGhOpKscGXLzO/CmIO+wgL15LTsxYsOh3HK7KjzocspQpxyD7pPWN8CUI
 M2IGLvYMzCaBAOzs6WO4P9xlJRNtUMK8lvAthnBiCeE2Nnu3Oajf8krR4DZmBcQh
 Q/GOACa1kuBMfqmWNrCVq3UNiFLxxAseShgxq9/E/dNe20daXOnxSaRGdRzTvAQF
 dRBEtHXdY0qDgLz3tVzBdTTmx3M2k4B4/t+VxnsFFVlvbr0OyOozvFH42tGeTw5t
 IBoXP9x87+Rpl6P6wW+ICketXQMRmdl40JXNjR96sXN94Y/Z4A==
 =vj/s
 -----END PGP SIGNATURE-----

Merge tag 'kvm-arm-for-v4.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/ARM updates for v4.9-rc4

- Kick the vcpu when a pending interrupt becomes pending again
- Prevent access to invalid interrupt registers
- Invalid TLBs when two vcpus from the same VM share a CPU
2016-11-11 11:13:36 +01:00
Linus Torvalds 66cecb6789 One NULL pointer dereference, and two fixes for regressions introduced
during the merge window.  The rest are fixes for MIPS, s390 and nested VMX.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.22 (GNU/Linux)
 
 iQEcBAABAgAGBQJYG2H5AAoJEL/70l94x66DK/cH/0jEQ3ynuLAd5CKux7JxI/EP
 msSJh1Xqr4+XhXZnuDpGQWrdsBlxoiqA6PsJrUTtyi4nQCDXlT8g+2MDuvqhWIHz
 7vw58j/EMJDCVQzYAbN5VDUfk13uB5aSWTo3M9Rf09v0hU1Ql7z8u4CtKEdLpN5Y
 LY9bT9fxUmXO7REKP7bdW6ZrDX/hUShYHgMqzXGFMyGBG3ym3a9bggXEzTCD6eNQ
 ioogQIWqg+icdhta0iLNAwFClPlcKB2/xo4IUuNgrPwGoHFGJN/8+qxT4+sVbp2B
 v8u1zOXlCFXBcskWE+yRRsGe72+mIzz6QScCyO+5HbhKYVfbE9H7KBlFX9rZZ2c=
 =IbKx
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "One NULL pointer dereference, and two fixes for regressions introduced
  during the merge window.

  The rest are fixes for MIPS, s390 and nested VMX"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  kvm: x86: Check memopp before dereference (CVE-2016-8630)
  kvm: nVMX: VMCLEAR an active shadow VMCS after last use
  KVM: x86: drop TSC offsetting kvm_x86_ops to fix KVM_GET/SET_CLOCK
  KVM: x86: fix wbinvd_dirty_mask use-after-free
  kvm/x86: Show WRMSR data is in hex
  kvm: nVMX: Fix kernel panics induced by illegal INVEPT/INVVPID types
  KVM: document lock orders
  KVM: fix OOPS on flush_work
  KVM: s390: Fix STHYI buffer alignment for diag224
  KVM: MIPS: Precalculate MMIO load resume PC
  KVM: MIPS: Make ERET handle ERL before EXL
  KVM: MIPS: Fix lazy user ASID regenerate for SMP
2016-11-04 13:08:05 -07:00
Shih-Wei Li d42c79701a KVM: arm/arm64: vgic: Kick VCPUs when queueing already pending IRQs
In cases like IPI, we could be queueing an interrupt for a VCPU
that is already running and is not about to exit, because the
VCPU has entered the VM with the interrupt pending and would
not trap on EOI'ing that interrupt. This could result to delays
in interrupt deliveries or even loss of interrupts.
To guarantee prompt interrupt injection, here we have to try to
kick the VCPU.

Signed-off-by: Shih-Wei Li <shihwei@cs.columbia.edu>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-11-04 17:56:56 +00:00
Andre Przywara 112b0b8f8f KVM: arm/arm64: vgic: Prevent access to invalid SPIs
In our VGIC implementation we limit the number of SPIs to a number
that the userland application told us. Accordingly we limit the
allocation of memory for virtual IRQs to that number.
However in our MMIO dispatcher we didn't check if we ever access an
IRQ beyond that limit, leading to out-of-bound accesses.
Add a test against the number of allocated SPIs in check_region().
Adjust the VGIC_ADDR_TO_INT macro to avoid an actual division, which
is not implemented on ARM(32).

[maz: cleaned-up original patch]

Cc: stable@vger.kernel.org
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-11-04 17:56:54 +00:00
Suraj Jitindar Singh ce35ef27d4 kvm/stats: Update kvm stats to clear on write to their debugfs entry
Various kvm vm and vcpu stats are provided via debugfs entries.
Currently there is no way to reset these stats back to zero.

Add the ability to clear (reset back to zero) these stats on a per stat
basis by writing to the debugfs files. Only a write value of 0 is accepted.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-11-02 21:32:17 +01:00
Paolo Bonzini 36343f6ea7 KVM: fix OOPS on flush_work
The conversion done by commit 3706feacd0 ("KVM: Remove deprecated
create_singlethread_workqueue") is broken.  It flushes a single work
item &irqfd->shutdown instead of all of them, and even worse if there
is no irqfd on the list then you get a NULL pointer dereference.
Revert the virt/kvm/eventfd.c part of that patch; to avoid the
deprecated function, just allocate our own workqueue---it does
not even have to be unbound---with alloc_workqueue.

Fixes: 3706feacd0
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-26 14:06:51 +02:00
Lorenzo Stoakes 0d73175982 mm: unexport __get_user_pages()
This patch unexports the low-level __get_user_pages() function.

Recent refactoring of the get_user_pages* functions allow flags to be
passed through get_user_pages() which eliminates the need for access to
this function from its one user, kvm.

We can see that the two calls to get_user_pages() which replace
__get_user_pages() in kvm_main.c are equivalent by examining their call
stacks:

  get_user_page_nowait():
    get_user_pages(start, 1, flags, page, NULL)
    __get_user_pages_locked(current, current->mm, start, 1, page, NULL, NULL,
			    false, flags | FOLL_TOUCH)
    __get_user_pages(current, current->mm, start, 1,
		     flags | FOLL_TOUCH | FOLL_GET, page, NULL, NULL)

  check_user_page_hwpoison():
    get_user_pages(addr, 1, flags, NULL, NULL)
    __get_user_pages_locked(current, current->mm, addr, 1, NULL, NULL, NULL,
			    false, flags | FOLL_TOUCH)
    __get_user_pages(current, current->mm, addr, 1, flags | FOLL_TOUCH, NULL,
		     NULL, NULL)

Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-24 19:13:20 -07:00
Lorenzo Stoakes d4944b0ece mm: remove write/force parameters from __get_user_pages_unlocked()
This removes the redundant 'write' and 'force' parameters from
__get_user_pages_unlocked() to make the use of FOLL_FORCE explicit in
callers as use of this flag can result in surprising behaviour (and
hence bugs) within the mm subsystem.

Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-18 14:13:37 -07:00
Radim Krčmář 45ca877ad0 KVM/ARM Changes for v4.9
- Various cleanups and removal of redundant code
  - Two important fixes for not using an in-kernel irqchip
  - A bit of optimizations
  - Handle SError exceptions and present them to guests if appropriate
  - Proxying of GICV access at EL2 if guest mappings are unsafe
  - GICv3 on AArch32 on ARMv8
  - Preparations for GICv3 save/restore, including ABI docs
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQEcBAABAgAGBQJX6rKQAAoJEEtpOizt6ddy8i4H/0bfB1EVukggoL/FfGeds/dg
 p2FG0oOsggcSBwK7VXUUvVllO7ioUssRCqqkn1e0/bCLtQrN4ex4PqJ3618EHFz/
 pLP72hf8Zl33rP3OVtPaDcxzjjKKdf+xGbBIv3AE7x7O5rFZg4lWHeWjy4yuhFv2
 Jm+8ul7JCxCMse08Xc90riou4i/jWjyoLadHbAoeX3tR+dVcZyOUZSlgAPI1bS/P
 rOQi/zkl3bT2R3kh28QuEFTrJ9BVTnmw25BRW8DNr6+CWmR9bpM6y7AGzOwrZ3FZ
 F1MbsPpN3ogcjvPg2QTYuOoqrwz8NLLHw5pR5YNj84VppjSpSsAhKU7Ug5Uhsr0=
 =1z/L
 -----END PGP SIGNATURE-----

Merge tag 'kvm-arm-for-v4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into next

KVM/ARM Changes for v4.9

 - Various cleanups and removal of redundant code
 - Two important fixes for not using an in-kernel irqchip
 - A bit of optimizations
 - Handle SError exceptions and present them to guests if appropriate
 - Proxying of GICV access at EL2 if guest mappings are unsafe
 - GICv3 on AArch32 on ARMv8
 - Preparations for GICv3 save/restore, including ABI docs
2016-09-29 16:01:51 +02:00
Christoffer Dall 0099b7701f KVM: arm/arm64: vgic: Don't flush/sync without a working vgic
If the vgic hasn't been created and initialized, we shouldn't attempt to
look at its data structures or flush/sync anything to the GIC hardware.

This fixes an issue reported by Alexander Graf when using a userspace
irqchip.

Fixes: 0919e84c0f ("KVM: arm/arm64: vgic-new: Add IRQ sync/flush framework")
Cc: stable@vger.kernel.org
Reported-by: Alexander Graf <agraf@suse.de>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-27 18:57:35 +02:00
Christoffer Dall 6fe407f2d1 KVM: arm64: Require in-kernel irqchip for PMU support
If userspace creates a PMU for the VCPU, but doesn't create an in-kernel
irqchip, then we end up in a nasty path where we try to take an
uninitialized spinlock, which can lead to all sorts of breakages.

Luckily, QEMU always creates the VGIC before the PMU, so we can
establish this as ABI and check for the VGIC in the PMU init stage.
This can be relaxed at a later time if we want to support PMU with a
userspace irqchip.

Cc: stable@vger.kernel.org
Cc: Shannon Zhao <shannon.zhao@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-27 18:57:07 +02:00
Vladimir Murzin acda5430be ARM: KVM: Support vgic-v3
This patch allows to build and use vgic-v3 in 32-bit mode.

Unfortunately, it can not be split in several steps without extra
stubs to keep patches independent and bisectable.  For instance,
virt/kvm/arm/vgic/vgic-v3.c uses function from vgic-v3-sr.c, handling
access to GICv3 cpu interface from the guest requires vgic_v3.vgic_sre
to be already defined.

It is how support has been done:

* handle SGI requests from the guest

* report configured SRE on access to GICv3 cpu interface from the guest

* required vgic-v3 macros are provided via uapi.h

* static keys are used to select GIC backend

* to make vgic-v3 build KVM_ARM_VGIC_V3 guard is removed along with
  the static inlines

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-22 13:22:21 +02:00
Vladimir Murzin d7d0a11e44 KVM: arm: vgic: Support 64-bit data manipulation on 32-bit host systems
We have couple of 64-bit registers defined in GICv3 architecture, so
unsigned long accesses to these registers will only access a single
32-bit part of that regitser. On the other hand these registers can't
be accessed as 64-bit with a single instruction like ldrd/strd or
ldmia/stmia if we run a 32-bit host because KVM does not support
access to MMIO space done by these instructions.

It means that a 32-bit guest accesses these registers in 32-bit
chunks, so the only thing we need to do is to ensure that
extract_bytes() always takes 64-bit data.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-22 13:21:59 +02:00
Vladimir Murzin e533a37f7b KVM: arm: vgic: Fix compiler warnings when built for 32-bit
Well, this patch is looking ahead of time, but we'll get following
compiler warnings as soon as we introduce vgic-v3 to 32-bit world

  CC      arch/arm/kvm/../../../virt/kvm/arm/vgic/vgic-mmio-v3.o
arch/arm/kvm/../../../virt/kvm/arm/vgic/vgic-mmio-v3.c: In function 'vgic_mmio_read_v3r_typer':
arch/arm/kvm/../../../virt/kvm/arm/vgic/vgic-mmio-v3.c:184:35: warning: left shift count >= width of type [-Wshift-count-overflow]
  value = (mpidr & GENMASK(23, 0)) << 32;
                                   ^
In file included from ./include/linux/kernel.h:10:0,
                 from ./include/asm-generic/bug.h:13,
                 from ./arch/arm/include/asm/bug.h:59,
                 from ./include/linux/bug.h:4,
                 from ./include/linux/io.h:23,
                 from ./arch/arm/include/asm/arch_gicv3.h:23,
                 from ./include/linux/irqchip/arm-gic-v3.h:411,
                 from arch/arm/kvm/../../../virt/kvm/arm/vgic/vgic-mmio-v3.c:14:
arch/arm/kvm/../../../virt/kvm/arm/vgic/vgic-mmio-v3.c: In function 'vgic_v3_dispatch_sgi':
./include/linux/bitops.h:6:24: warning: left shift count >= width of type [-Wshift-count-overflow]
 #define BIT(nr)   (1UL << (nr))
                        ^
arch/arm/kvm/../../../virt/kvm/arm/vgic/vgic-mmio-v3.c:614:20: note: in expansion of macro 'BIT'
  broadcast = reg & BIT(ICC_SGI1R_IRQ_ROUTING_MODE_BIT);
                    ^
Let's fix them now.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-22 13:21:48 +02:00
Vladimir Murzin 7a1ff70828 KVM: arm64: vgic-its: Introduce config option to guard ITS specific code
By now ITS code guarded with KVM_ARM_VGIC_V3 config option which was
introduced to hide everything specific to vgic-v3 from 32-bit world.
We are going to support vgic-v3 in 32-bit world and KVM_ARM_VGIC_V3
will gone, but we don't have support for ITS there yet and we need to
continue keeping ITS away.
Introduce the new config option to prevent ITS code being build in
32-bit mode when support for vgic-v3 is done.

Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-22 13:21:47 +02:00
Vladimir Murzin 19f0ece439 arm64: KVM: Move vgic-v3 save/restore to virt/kvm/arm/hyp
So we can reuse the code under arch/arm

Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-22 13:21:46 +02:00
Vladimir Murzin 5a7a8426b2 arm64: KVM: Use static keys for selecting the GIC backend
Currently GIC backend is selected via alternative framework and this
is fine. We are going to introduce vgic-v3 to 32-bit world and there
we don't have patching framework in hand, so we can either check
support for GICv3 every time we need to choose which backend to use or
try to optimise it by using static keys. The later looks quite
promising because we can share logic involved in selecting GIC backend
between architectures if both uses static keys.

This patch moves arm64 from alternative to static keys framework for
selecting GIC backend. For that we embed static key into vgic_global
and enable the key during vgic initialisation based on what has
already been exposed by the host GIC driver.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-22 13:21:35 +02:00
Luiz Capitulino 45b5939e50 kvm: create per-vcpu dirs in debugfs
This commit adds the ability for archs to export
per-vcpu information via a new per-vcpu dir in
the VM's debugfs directory.

If kvm_arch_has_vcpu_debugfs() returns true, then KVM
will create a vcpu dir for each vCPU in the VM's
debugfs directory. Then kvm_arch_create_vcpu_debugfs()
is responsible for populating each vcpu directory
with arch specific entries.

The per-vcpu path in debugfs will look like:

/sys/kernel/debug/kvm/29162-10/vcpu0
/sys/kernel/debug/kvm/29162-10/vcpu1

This is all arch specific for now because the only
user of this interface (x86) wants to export x86-specific
per-vcpu information to user-space.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-16 16:57:47 +02:00
Luiz Capitulino 9d5a1dcebf kvm: kvm_destroy_vm_debugfs(): check debugfs_stat_data pointer
This make it possible to call kvm_destroy_vm_debugfs() from
kvm_create_vm_debugfs() in error conditions.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-16 16:57:46 +02:00
Paolo Bonzini ad53e35ae5 Merge branch 'kvm-ppc-next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD
Paul Mackerras writes:

    The highlights are:

    * Reduced latency for interrupts from PCI pass-through devices, from
      Suresh Warrier and me.
    * Halt-polling implementation from Suraj Jitindar Singh.
    * 64-bit VCPU statistics, also from Suraj.
    * Various other minor fixes and improvements.
2016-09-13 15:20:55 +02:00
Paolo Bonzini 5d947a1447 KVM: ARM: cleanup kvm_timer_hyp_init
Remove two unnecessary labels now that kvm_timer_hyp_init is not
creating its own workqueue anymore.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08 12:54:00 +02:00
Marc Zyngier 3272f0d08e arm64: KVM: Inject a vSerror if detecting a bad GICV access at EL2
If, when proxying a GICV access at EL2, we detect that the guest is
doing something silly, report an EL1 SError instead ofgnoring the
access.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08 12:53:00 +02:00
Marc Zyngier a07d3b07a8 arm64: KVM: vgic-v2: Enable GICV access from HYP if access from guest is unsafe
So far, we've been disabling KVM on systems where the GICV region couldn't
be safely given to a guest. Now that we're able to handle this access
safely by emulating it in HYP, we can enable this feature when we detect
an unsafe configuration.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08 12:53:00 +02:00
Marc Zyngier bf8feb3964 arm64: KVM: vgic-v2: Add GICV access from HYP
Now that we have the necessary infrastructure to handle MMIO accesses
in HYP, perform the GICV access on behalf of the guest. This requires
checking that the access is strictly 32bit, properly aligned, and
falls within the expected range.

When all condition are satisfied, we perform the access and tell
the rest of the HYP code that the instruction has been correctly
emulated.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08 12:53:00 +02:00
Marc Zyngier fb5ee369cc arm64: KVM: vgic-v2: Add the GICV emulation infrastructure
In order to efficiently perform the GICV access on behalf of the
guest, we need to be able to avoid going back all the way to
the host kernel.

For this, we introduce a new hook in the world switch code,
conveniently placed just after populating the fault info.
At that point, we only have saved/restored the GP registers,
and we can quickly perform all the required checks (data abort,
translation fault, valid faulting syndrome, not an external
abort, not a PTW).

Coming back from the emulation code, we need to skip the emulated
instruction. This involves an additional bit of save/restore in
order to be able to access the guest's PC (and possibly CPSR if
this is a 32bit guest).

At this stage, no emulation code is provided.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08 12:53:00 +02:00
Marc Zyngier 8cebe750c4 arm64: KVM: Make kvm_skip_instr32 available to HYP
As we plan to do some emulation at HYP, let's make kvm_skip_instr32
as part of the hyp_text section. This doesn't preclude the kernel
from using it.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08 12:53:00 +02:00
Marc Zyngier 3aedd5c49e arm: KVM: Use common AArch32 conditional execution code
Add the bit of glue and const-ification that is required to use
the code inherited from the arm64 port, and move over to it.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08 12:53:00 +02:00
Marc Zyngier 427d7cacf9 arm64: KVM: Move the AArch32 conditional execution to common code
It would make some sense to share the conditional execution code
between 32 and 64bit. In order to achieve this, let's move that
code to virt/kvm/arm/aarch32.c. While we're at it, drop a
superfluous BUG_ON() that wasn't that useful.

Following patches will migrate the 32bit port to that code base.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08 12:53:00 +02:00
Marc Zyngier 55d7cad6a9 KVM: arm: vgic: Drop build compatibility hack for older kernel versions
As kvm_set_routing_entry() was changing prototype between 4.7 and 4.8,
an ugly hack was put in place in order to survive both building in
-next and the merge window.

Now that everything has been merged, let's dump the compatibility
hack for good.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08 12:53:00 +02:00
Christoffer Dall 1fe0009833 KVM: arm/arm64: Rename vgic_attr_regs_access to vgic_attr_regs_access_v2
Just a rename so we can implement a v3-specific function later.

We take the chance to get rid of the V2/V3 ops comments as well.

No functional change.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
2016-09-08 12:53:00 +02:00
Christoffer Dall ba7b9169b5 KVM: arm/arm64: Factor out vgic_attr_regs_access functionality
As we are about to deal with multiple data types and situations where
the vgic should not be initialized when doing userspace accesses on the
register attributes, factor out the functionality of
vgic_attr_regs_access into smaller bits which can be reused by a new
function later.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
2016-09-08 12:53:00 +02:00
Suraj Jitindar Singh 8a7e75d47b KVM: Add provisioning for ulong vm stats and u64 vcpu stats
vms and vcpus have statistics associated with them which can be viewed
within the debugfs. Currently it is assumed within the vcpu_stat_get() and
vm_stat_get() functions that all of these statistics are represented as
u32s, however the next patch adds some u64 vcpu statistics.

Change all vcpu statistics to u64 and modify vcpu_stat_get() accordingly.
Since vcpu statistics are per vcpu, they will only be updated by a single
vcpu at a time so this shouldn't present a problem on 32-bit machines
which can't atomically increment 64-bit numbers. However vm statistics
could potentially be updated by multiple vcpus from that vm at a time.
To avoid the overhead of atomics make all vm statistics ulong such that
they are 64-bit on 64-bit systems where they can be atomically incremented
and are 32-bit on 32-bit systems which may not be able to atomically
increment 64-bit numbers. Modify vm_stat_get() to expect ulongs.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: David Matlack <dmatlack@google.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-08 12:25:37 +10:00
Bhaktipriya Shridhar 3706feacd0 KVM: Remove deprecated create_singlethread_workqueue
The workqueue "irqfd_cleanup_wq" queues a single work item
&irqfd->shutdown and hence doesn't require ordering. It is a host-wide
workqueue for issuing deferred shutdown requests aggregated from all
vm* instances. It is not being used on a memory reclaim path.
Hence, it has been converted to use system_wq.
The work item has been flushed in kvm_irqfd_release().

The workqueue "wqueue" queues a single work item &timer->expired
and hence doesn't require ordering. Also, it is not being used on
a memory reclaim path. Hence, it has been converted to use system_wq.

System workqueues have been able to handle high level of concurrency
for a long time now and hence it's not required to have a singlethreaded
workqueue just to gain concurrency. Unlike a dedicated per-cpu workqueue
created with create_singlethread_workqueue(), system_wq allows multiple
work items to overlap executions even on the same CPU; however, a
per-cpu workqueue doesn't have any CPU locality or global ordering
guarantee unless the target CPU is explicitly specified and thus the
increase of local concurrency shouldn't make any difference.

Signed-off-by: Bhaktipriya Shridhar <bhaktipriya96@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-07 19:34:28 +02:00
Paolo Bonzini 2eeb321fd2 KVM/ARM Fixes for v4.8-rc3
This tag contains the following fixes on top of v4.8-rc1:
  - ITS init issues
  - ITS error handling issues
  - ITS IRQ leakage fix
  - Plug a couple of ITS race conditions
  - An erratum workaround for timers
  - Some removal of misleading use of errors and comments
  - A fix for GICv3 on 32-bit guests
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQEcBAABAgAGBQJXtLicAAoJEEtpOizt6ddyEC4H/16IngntN6Gz1WPwtBBelgyj
 ZfU970uzGOyDtDOeOX1NT+gJpkDvUMhsNlngWnMrMwqqqPVKdE4XBShPiW2v53E7
 JquDTd2kKl+OO9e9XnkLw9yUcARmJFKIjHdISlg+E78t2kcNHn+XB2jrfTLKQVl8
 tk1ztDALb4LXSGYPZQ/uHTYp9U0qei+2SbbQufRcdQ3ggyxLDwPP2aO25amctzEP
 0Y42tlnNoZj7yBBp0X9BWRrHF2AZuOp+qBJnpFiQdsgLL6G1P3DcU/t9+KDjVBVr
 LYKN8jId2r5eyGGg8aKb4I3trevayToWhDw/jzarrTNAovB1cp8G5J7ozfmeS3g=
 =4PCW
 -----END PGP SIGNATURE-----

Merge tag 'kvm-arm-for-v4.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/ARM Fixes for v4.8-rc3

This tag contains the following fixes on top of v4.8-rc1:
 - ITS init issues
 - ITS error handling issues
 - ITS IRQ leakage fix
 - Plug a couple of ITS race conditions
 - An erratum workaround for timers
 - Some removal of misleading use of errors and comments
 - A fix for GICv3 on 32-bit guests
2016-08-18 12:19:19 +02:00
Marc Zyngier cabdc5c59a KVM: arm/arm64: timer: Workaround misconfigured timer interrupt
Similarily to f005bd7e3b ("clocksource/arm_arch_timer: Force
per-CPU interrupt to be level-triggered"), make sure we can
survive an interrupt that has been misconfigured as edge-triggered
by forcing it to be level-triggered (active low is assumed, but
the GIC doesn't really care whether this is high or low).

Hopefully, the amount of shouting in the kernel log will convince
the user to do something about their firmware.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-08-17 12:23:47 +02:00
Andre Przywara 286054a7a8 KVM: arm64: ITS: avoid re-mapping LPIs
When a guest wants to map a device-ID/event-ID combination that is
already mapped, we may end up in a situation where an LPI is never
"put", thus never being freed.
Since the GICv3 spec says that mapping an already mapped LPI is
UNPREDICTABLE, lets just bail out early in this situation to avoid
any potential leaks.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-08-16 19:27:22 +02:00
Andre Przywara 505a19eec4 KVM: arm64: check for ITS device on MSI injection
When userspace provides the doorbell address for an MSI to be
injected into the guest, we find a KVM device which feels responsible.
Lets check that this device is really an emulated ITS before we make
real use of the container_of-ed pointer.

  [ Moved NULL-pointer check to caller of static function
    - Christoffer ]

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-08-15 23:00:22 +02:00
Andre Przywara c7735769d5 KVM: arm64: ITS: move ITS registration into first VCPU run
Currently we register an ITS device upon userland issuing the CTLR_INIT
ioctl to mark initialization of the ITS as done.
This deviates from the initialization sequence of the existing GIC
devices and does not play well with the way QEMU handles things.
To be more in line with what we are used to, register the ITS(es) just
before the first VCPU is about to run, so in the map_resources() call.
This involves iterating through the list of KVM devices and map each
ITS that we find.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-08-15 23:00:21 +02:00
Christoffer Dall d9ae449b3d KVM: arm64: vgic-its: Make updates to propbaser/pendbaser atomic
There are two problems with the current implementation of the MMIO
handlers for the propbaser and pendbaser:

First, the write to the value itself is not guaranteed to be an atomic
64-bit write so two concurrent writes to the structure field could be
intermixed.

Second, because we do a read-modify-update operation without any
synchronization, if we have two 32-bit accesses to separate parts of the
register, we can loose one of them.

By using the atomic cmpxchg64 we should cover both issues above.

Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-08-15 23:00:20 +02:00
Christoffer Dall a28ebea2ad KVM: Protect device ops->create and list_add with kvm->lock
KVM devices were manipulating list data structures without any form of
synchronization, and some implementations of the create operations also
suffered from a lack of synchronization.

Now when we've split the xics create operation into create and init, we
can hold the kvm->lock mutex while calling the create operation and when
manipulating the devices list.

The error path in the generic code gets slightly ugly because we have to
take the mutex again and delete the device from the list, but holding
the mutex during anon_inode_getfd or releasing/locking the mutex in the
common non-error path seemed wrong.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-08-12 12:01:27 +02:00
Christoffer Dall 023e9fddc3 KVM: PPC: Move xics_debugfs_init out of create
As we are about to hold the kvm->lock during the create operation on KVM
devices, we should move the call to xics_debugfs_init into its own
function, since holding a mutex over extended amounts of time might not
be a good idea.

Introduce an init operation on the kvm_device_ops struct which cannot
fail and call this, if configured, after the device has been created.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-08-12 12:01:26 +02:00
Christoffer Dall 2cccbb368a KVM: arm64: vgic-its: Plug race in vgic_put_irq
Right now the following sequence of events can happen:

  1. Thread X calls vgic_put_irq
  2. Thread Y calls vgic_add_lpi
  3. Thread Y gets lpi_list_lock
  4. Thread X drops the ref count to 0 and blocks on lpi_list_lock
  5. Thread Y finds the irq via the lpi_list_lock, raises the ref
     count to 1, and release the lpi_list_lock.
  6. Thread X proceeds and frees the irq.

Avoid this by holding the spinlock around the kref_put.

Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-08-10 11:41:54 +02:00
Christoffer Dall 99e5e886a0 KVM: arm64: vgic-its: Handle errors from vgic_add_lpi
During low memory conditions, we could be dereferencing a NULL pointer
when vgic_add_lpi fails to allocate memory.

Consider for example this call sequence:

  vgic_its_cmd_handle_mapi
      itte->irq = vgic_add_lpi(kvm, lpi_nr);
          update_lpi_config(kvm, itte->irq, NULL);
              ret = kvm_read_guest(kvm, propbase + irq->intid
	                                             ^^^^
						     kaboom?

Instead, return an error pointer from vgic_add_lpi and check the return
value from its single caller.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-08-10 11:41:35 +02:00
Andre Przywara fd837b08d9 KVM: arm64: ITS: return 1 on successful MSI injection
According to the KVM API documentation a successful MSI injection
should return a value > 0 on success.
Return possible errors in vgic_its_trigger_msi() and report a
successful injection back to userland, while also reporting the
case where the MSI could not be delivered due to the guest not
having the LPI mapped, for instance.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-08-09 16:43:23 +02:00
Paolo Bonzini 6f49b2f341 KVM/ARM Changes for v4.8 - Take 2
Includes GSI routing support to go along with the new VGIC and a small fix that
 has been cooking in -next for a while.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQEcBAABAgAGBQJXoydqAAoJEEtpOizt6ddyM3oH/1A4VeG/J9q4fBPXqY2tVWXs
 c3P7UgNcrEgUNs/F9ykQY/lb31deecUzaBt1OyTf+RlsNbihq3dQdYcBhxtUODw/
 Faok582ya3UFgLW+IRHcID0EbkVOpIzMhOStYsnU/Dz7HG1JL9HdPzwkid7iu9LT
 fI6yrrBnJFjdWAAQ4BkcEKBENRsY8NTs7jX5vnFA92MkUBby7BmariPDD3FtrB+f
 Ob9B7CxM30pNqsN7OA/QvFOHMJHxf3s1TBKwmPHe5TLIfSzV1YxcEGiMc0lWqF4v
 BT8ZeMGCtjDw94tND1DskfQQRPaMqPmGuRTrAW/IuE2n92bFtbqIqs7Cbw0fzLE=
 =Vm6Q
 -----END PGP SIGNATURE-----

Merge tag 'kvm-arm-for-4.8-take2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/ARM Changes for v4.8 - Take 2

Includes GSI routing support to go along with the new VGIC and a small fix that
has been cooking in -next for a while.
2016-08-04 13:59:56 +02:00
Linus Torvalds 221bb8a46e - ARM: GICv3 ITS emulation and various fixes. Removal of the old
VGIC implementation.
 
 - s390: support for trapping software breakpoints, nested virtualization
 (vSIE), the STHYI opcode, initial extensions for CPU model support.
 
 - MIPS: support for MIPS64 hosts (32-bit guests only) and lots of cleanups,
 preliminary to this and the upcoming support for hardware virtualization
 extensions.
 
 - x86: support for execute-only mappings in nested EPT; reduced vmexit
 latency for TSC deadline timer (by about 30%) on Intel hosts; support for
 more than 255 vCPUs.
 
 - PPC: bugfixes.
 
 The ugly bit is the conflicts.  A couple of them are simple conflicts due
 to 4.7 fixes, but most of them are with other trees. There was definitely
 too much reliance on Acked-by here.  Some conflicts are for KVM patches
 where _I_ gave my Acked-by, but the worst are for this pull request's
 patches that touch files outside arch/*/kvm.  KVM submaintainers should
 probably learn to synchronize better with arch maintainers, with the
 latter providing topic branches whenever possible instead of Acked-by.
 This is what we do with arch/x86.  And I should learn to refuse pull
 requests when linux-next sends scary signals, even if that means that
 submaintainers have to rebase their branches.
 
 Anyhow, here's the list:
 
 - arch/x86/kvm/vmx.c: handle_pcommit and EXIT_REASON_PCOMMIT was removed
 by the nvdimm tree.  This tree adds handle_preemption_timer and
 EXIT_REASON_PREEMPTION_TIMER at the same place.  In general all mentions
 of pcommit have to go.
 
 There is also a conflict between a stable fix and this patch, where the
 stable fix removed the vmx_create_pml_buffer function and its call.
 
 - virt/kvm/kvm_main.c: kvm_cpu_notifier was removed by the hotplug tree.
 This tree adds kvm_io_bus_get_dev at the same place.
 
 - virt/kvm/arm/vgic.c: a few final bugfixes went into 4.7 before the
 file was completely removed for 4.8.
 
 - include/linux/irqchip/arm-gic-v3.h: this one is entirely our fault;
 this is a change that should have gone in through the irqchip tree and
 pulled by kvm-arm.  I think I would have rejected this kvm-arm pull
 request.  The KVM version is the right one, except that it lacks
 GITS_BASER_PAGES_SHIFT.
 
 - arch/powerpc: what a mess.  For the idle_book3s.S conflict, the KVM
 tree is the right one; everything else is trivial.  In this case I am
 not quite sure what went wrong.  The commit that is causing the mess
 (fd7bacbca4, "KVM: PPC: Book3S HV: Fix TB corruption in guest exit
 path on HMI interrupt", 2016-05-15) touches both arch/powerpc/kernel/
 and arch/powerpc/kvm/.  It's large, but at 396 insertions/5 deletions
 I guessed that it wasn't really possible to split it and that the 5
 deletions wouldn't conflict.  That wasn't the case.
 
 - arch/s390: also messy.  First is hypfs_diag.c where the KVM tree
 moved some code and the s390 tree patched it.  You have to reapply the
 relevant part of commits 6c22c98637, plus all of e030c1125e, to
 arch/s390/kernel/diag.c.  Or pick the linux-next conflict
 resolution from http://marc.info/?l=kvm&m=146717549531603&w=2.
 Second, there is a conflict in gmap.c between a stable fix and 4.8.
 The KVM version here is the correct one.
 
 I have pushed my resolution at refs/heads/merge-20160802 (commit
 3d1f53419842) at git://git.kernel.org/pub/scm/virt/kvm/kvm.git.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.22 (GNU/Linux)
 
 iQEcBAABAgAGBQJXoGm7AAoJEL/70l94x66DugQIAIj703ePAFepB/fCrKHkZZia
 SGrsBdvAtNsOhr7FQ5qvvjLxiv/cv7CymeuJivX8H+4kuUHUllDzey+RPHYHD9X7
 U6n1PdCH9F15a3IXc8tDjlDdOMNIKJixYuq1UyNZMU6NFwl00+TZf9JF8A2US65b
 x/41W98ilL6nNBAsoDVmCLtPNWAqQ3lajaZELGfcqRQ9ZGKcAYOaLFXHv2YHf2XC
 qIDMf+slBGSQ66UoATnYV2gAopNlWbZ7n0vO6tE2KyvhHZ1m399aBX1+k8la/0JI
 69r+Tz7ZHUSFtmlmyByi5IAB87myy2WQHyAPwj+4vwJkDGPcl0TrupzbG7+T05Y=
 =42ti
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:

 - ARM: GICv3 ITS emulation and various fixes.  Removal of the
   old VGIC implementation.

 - s390: support for trapping software breakpoints, nested
   virtualization (vSIE), the STHYI opcode, initial extensions
   for CPU model support.

 - MIPS: support for MIPS64 hosts (32-bit guests only) and lots
   of cleanups, preliminary to this and the upcoming support for
   hardware virtualization extensions.

 - x86: support for execute-only mappings in nested EPT; reduced
   vmexit latency for TSC deadline timer (by about 30%) on Intel
   hosts; support for more than 255 vCPUs.

 - PPC: bugfixes.

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (302 commits)
  KVM: PPC: Introduce KVM_CAP_PPC_HTM
  MIPS: Select HAVE_KVM for MIPS64_R{2,6}
  MIPS: KVM: Reset CP0_PageMask during host TLB flush
  MIPS: KVM: Fix ptr->int cast via KVM_GUEST_KSEGX()
  MIPS: KVM: Sign extend MFC0/RDHWR results
  MIPS: KVM: Fix 64-bit big endian dynamic translation
  MIPS: KVM: Fail if ebase doesn't fit in CP0_EBase
  MIPS: KVM: Use 64-bit CP0_EBase when appropriate
  MIPS: KVM: Set CP0_Status.KX on MIPS64
  MIPS: KVM: Make entry code MIPS64 friendly
  MIPS: KVM: Use kmap instead of CKSEG0ADDR()
  MIPS: KVM: Use virt_to_phys() to get commpage PFN
  MIPS: Fix definition of KSEGX() for 64-bit
  KVM: VMX: Add VMCS to CPU's loaded VMCSs before VMPTRLD
  kvm: x86: nVMX: maintain internal copy of current VMCS
  KVM: PPC: Book3S HV: Save/restore TM state in H_CEDE
  KVM: PPC: Book3S HV: Pull out TM state save/restore into separate procedures
  KVM: arm64: vgic-its: Simplify MAPI error handling
  KVM: arm64: vgic-its: Make vgic_its_cmd_handle_mapi similar to other handlers
  KVM: arm64: vgic-its: Turn device_id validation into generic ID validation
  ...
2016-08-02 16:11:27 -04:00
Linus Torvalds a6408f6cb6 Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull smp hotplug updates from Thomas Gleixner:
 "This is the next part of the hotplug rework.

   - Convert all notifiers with a priority assigned

   - Convert all CPU_STARTING/DYING notifiers

     The final removal of the STARTING/DYING infrastructure will happen
     when the merge window closes.

  Another 700 hundred line of unpenetrable maze gone :)"

* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (70 commits)
  timers/core: Correct callback order during CPU hot plug
  leds/trigger/cpu: Move from CPU_STARTING to ONLINE level
  powerpc/numa: Convert to hotplug state machine
  arm/perf: Fix hotplug state machine conversion
  irqchip/armada: Avoid unused function warnings
  ARC/time: Convert to hotplug state machine
  clocksource/atlas7: Convert to hotplug state machine
  clocksource/armada-370-xp: Convert to hotplug state machine
  clocksource/exynos_mct: Convert to hotplug state machine
  clocksource/arm_global_timer: Convert to hotplug state machine
  rcu: Convert rcutree to hotplug state machine
  KVM/arm/arm64/vgic-new: Convert to hotplug state machine
  smp/cfd: Convert core to hotplug state machine
  x86/x2apic: Convert to CPU hotplug state machine
  profile: Convert to hotplug state machine
  timers/core: Convert to hotplug state machine
  hrtimer: Convert to hotplug state machine
  x86/tboot: Convert to hotplug state machine
  arm64/armv8 deprecated: Convert to hotplug state machine
  hwtracing/coresight-etm4x: Convert to hotplug state machine
  ...
2016-07-29 13:55:30 -07:00
Marc Zyngier 3f312db6b6 KVM: arm: vgic-irqfd: Workaround changing kvm_set_routing_entry prototype
kvm_set_routing_entry is changing in -next, and causes things to
explode. Add a temporary workaround that should be dropped when
we hit 4.8-rc1

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-24 10:37:38 +01:00
Radim Krčmář 912902ce78 KVM/ARM changes for Linux 4.8
- GICv3 ITS emulation
 - Simpler idmap management that fixes potential TLB conflicts
 - Honor the kernel protection in HYP mode
 - Removal of the old vgic implementation
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJXkk6wAAoJECPQ0LrRPXpDkIQP/iJ2yXTxrfbJoyaVq1vuMn3R
 UFhVwNXP8OEjQrmp5lvMBazB1MRBkNDzlVXL1fSb+ijKmbIELOqHhO6ijrkK4zmc
 0Ie0x5Bt4gIFPTZyZORVpy1eU/0YFGWERAfsAjYdMCeKwHjaUCRSrZBXF2YsFTfo
 Hh/ILvHa8TjUXWsQXvtZCL6AAnkDKBsbDWqsq5zspuT+PA8umI+dGLIiULXBpc4t
 S2TCDxOU1JgsAn+Y0XVbPXV9id+bs5LRd6nNH/RmipIVqWmukSrScXOjg/po/l2S
 laO4tHmyEeN6ecnCxWttpjacNwyTDNh5n3lL1ceBnBZFqn1k/7NjqV3fQzJxGd1T
 1U6edE9+EuS9uXWF5XcEuAD660EiMs4FLVSjPgqYQtto3gOHilmuWL9eeeOOgCem
 Lknnu/7G8h36PaQuLnEXWXQb7jeS2rTuC0RqxCG62gD9UWEJTckRz5pRh/e6gz7n
 ZVXMrwGiVZ3zR78qE6i2j5CZ6A0BMAK3nZ85AI3kmgKg0CfVY28uPOj8llAOaYm+
 0XVdfRj7ed75eu3GobjHUyZ0fQ40jovmH2vy3mupBm5XBUHgH/j6X510KJ1UTLWI
 C2EO9KogbjoVeu60mQi4bKGSPi8/wdgYqVft/Qzl5D5iFvQ7Ia+TQNMArCQazBID
 Ihe1E09NGrHjV3Yw/GWV
 =2Del
 -----END PGP SIGNATURE-----

Merge tag 'kvm-arm-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into next

KVM/ARM changes for Linux 4.8

- GICv3 ITS emulation
- Simpler idmap management that fixes potential TLB conflicts
- Honor the kernel protection in HYP mode
- Removal of the old vgic implementation
2016-07-22 20:27:26 +02:00
Eric Auger 995a0ee980 KVM: arm/arm64: Enable MSI routing
Up to now, only irqchip routing entries could be set. This patch
adds the capability to insert MSI routing entries.

For ARM64, let's also increase KVM_MAX_IRQ_ROUTES to 4096: this
include SPI irqchip routes plus MSI routes. In the future this
might be extended.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-22 18:52:03 +01:00
Eric Auger 180ae7b118 KVM: arm/arm64: Enable irqchip routing
This patch adds compilation and link against irqchip.

Main motivation behind using irqchip code is to enable MSI
routing code. In the future irqchip routing may also be useful
when targeting multiple irqchips.

Routing standard callbacks now are implemented in vgic-irqfd:
- kvm_set_routing_entry
- kvm_set_irq
- kvm_set_msi

They only are supported with new_vgic code.

Both HAVE_KVM_IRQCHIP and HAVE_KVM_IRQ_ROUTING are defined.
KVM_CAP_IRQ_ROUTING is advertised and KVM_SET_GSI_ROUTING is allowed.

So from now on IRQCHIP routing is enabled and a routing table entry
must exist for irqfd injection to succeed for a given SPI. This patch
builds a default flat irqchip routing table (gsi=irqchip.pin) covering
all the VGIC SPI indexes. This routing table is overwritten by the
first first user-space call to KVM_SET_GSI_ROUTING ioctl.

MSI routing setup is not yet allowed.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-22 18:52:01 +01:00
Eric Auger ebe915259c KVM: irqchip: Convey devid to kvm_set_msi
on ARM, a devid field is populated in kvm_msi struct in case the
flag is set to KVM_MSI_VALID_DEVID. Let's propagate both flags and
devid field in kvm_kernel_irq_routing_entry.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-22 18:51:58 +01:00
Marc Zyngier 3a88bded20 KVM: arm64: vgic-its: Simplify MAPI error handling
If we care to move all the checks that do not involve any memory
allocation, we can simplify the MAPI error handling. Let's do that,
it cannot hurt.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:15:20 +01:00
Marc Zyngier a3e7aa271e KVM: arm64: vgic-its: Make vgic_its_cmd_handle_mapi similar to other handlers
vgic_its_cmd_handle_mapi has an extra "subcmd" argument, which is
already contained in the command buffer that all command handlers
obtain from the command queue. Let's drop it, as it is not that
useful.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:15:19 +01:00
Marc Zyngier 6d03a68f80 KVM: arm64: vgic-its: Turn device_id validation into generic ID validation
There is no need to have separate functions to validate devices
and collections, as the architecture doesn't really distinguish the
two, and they are supposed to be managed the same way.

Let's turn the DevID checker into a generic one.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:15:19 +01:00
Marc Zyngier bb7176449f KVM: arm64: vgic-its: Add pointer to corresponding kvm_device
Going from the ITS structure to the corresponding KVM structure
would be quite handy at times. The kvm_device pointer that is
passed at create time is quite convenient for this, so let's
keep a copy of it in the vgic_its structure.

This will be put to a good use in subsequent patches.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:15:18 +01:00
Marc Zyngier 17a21f58ff KVM: arm64: vgic-its: Add collection allocator/destructor
Instead of spreading random allocations all over the place,
consolidate allocation/init/freeing of collections in a pair
of constructor/destructor.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:15:18 +01:00
Marc Zyngier d6c7f865f0 KVM: arm64: vgic-its: Fix L2 entry validation for indirect tables
When checking that the storage address of a device entry is valid,
it is critical to compute the actual address of the entry, rather
than relying on the beginning of the page to match a CPU page of
the same size: for example, if the guest places the table at the
last 64kB boundary of RAM, but RAM size isn't a multiple of 64kB...

Fix this by computing the actual offset of the device ID in the
L2 page, and check the corresponding GFN.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:15:18 +01:00
Marc Zyngier 333a53ff7f KVM: arm64: vgic-its: Validate the device table L1 entry
Checking that the device_id fits if the table, and we must make
sure that the associated memory is also accessible.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:15:17 +01:00
Marc Zyngier b90338b7cb KVM: arm64: vgic-its: Fix misleading nr_entries in vgic_its_check_device_id
The nr_entries variable in vgic_its_check_device_id actually
describe the size of the L1 table, and not the number of
entries in this table.

Rename it to l1_tbl_size, so that we can now change the code
with a better understanding of what is what.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:15:17 +01:00
Marc Zyngier 7e3963a515 KVM: arm64: vgic-its: Fix vgic_its_check_device_id BE handling
The ITS tables are stored in LE format. If the host is reading
a L1 table entry to check its validity, it must convert it to
the CPU endianness.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:15:16 +01:00
Marc Zyngier c0091073dd KVM: arm64: vgic-its: Fix handling of indirect tables
The current code will fail on valid indirect tables, and happily
use the ones that are pointing out of the guest RAM. Funny what a
small "!" can do for you...

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:15:16 +01:00
Marc Zyngier d97594e6bc KVM: arm64: vgic-its: Generalize use of vgic_get_irq_kref
Instead of sprinkling raw kref_get() calls everytime we cannot
do a normal vgic_get_irq(), use the existing vgic_get_irq_kref(),
which does the same thing and is paired with a vgic_put_irq().

vgic_get_irq_kref is moved to vgic.h in order to be easily shared.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:15:16 +01:00
Eric Auger 9d5fcb9dd7 KVM: arm/arm64: Fix vGICv2 KVM_DEV_ARM_VGIC_GRP_CPU/DIST_REGS
For VGICv2 save and restore the CPU interface registers
are accessed. Restore the modality which has been altered.
Also explicitly set the iodev_type for both the DIST and CPU
interface.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:15:15 +01:00
Andre Przywara 0e4e82f154 KVM: arm64: vgic-its: Enable ITS emulation as a virtual MSI controller
Now that all ITS emulation functionality is in place, we advertise
MSI functionality to userland and also the ITS device to the guest - if
userland has configured that.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:14:38 +01:00
Andre Przywara 2891a7dfb6 KVM: arm64: vgic-its: Implement MSI injection in ITS emulation
When userland wants to inject an MSI into the guest, it uses the
KVM_SIGNAL_MSI ioctl, which carries the doorbell address along with
the payload and the device ID.
With the help of the KVM IO bus framework we learn the corresponding
ITS from the doorbell address. We then use our wrapper functions to
iterate the linked lists and find the proper Interrupt Translation Table
Entry (ITTE) and thus the corresponding struct vgic_irq to finally set
the pending bit.
We also provide the handler for the ITS "INT" command, which allows a
guest to trigger an MSI via the ITS command queue. Since this one knows
about the right ITS already, we directly call the MMIO handler function
without using the kvm_io_bus framework.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:14:38 +01:00
Andre Przywara df9f58fbea KVM: arm64: vgic-its: Implement ITS command queue command handlers
The connection between a device, an event ID, the LPI number and the
associated CPU is stored in in-memory tables in a GICv3, but their
format is not specified by the spec. Instead software uses a command
queue in a ring buffer to let an ITS implementation use its own
format.
Implement handlers for the various ITS commands and let them store
the requested relation into our own data structures. Those data
structures are protected by the its_lock mutex.
Our internal ring buffer read and write pointers are protected by the
its_cmd mutex, so that only one VCPU per ITS can handle commands at
any given time.
Error handling is very basic at the moment, as we don't have a good
way of communicating errors to the guest (usually an SError).
The INT command handler is missing from this patch, as we gain the
capability of actually injecting MSIs into the guest only later on.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:14:38 +01:00
Andre Przywara f9f77af9e2 KVM: arm64: vgic-its: Allow updates of LPI configuration table
The (system-wide) LPI configuration table is held in a table in
(guest) memory. To achieve reasonable performance, we cache this data
in our struct vgic_irq. If the guest updates the configuration data
(which consists of the enable bit and the priority value), it issues
an INV or INVALL command to allow us to update our information.
Provide functions that update that information for one LPI or all LPIs
mapped to a specific collection.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:14:37 +01:00
Andre Przywara 33d3bc9556 KVM: arm64: vgic-its: Read initial LPI pending table
The LPI pending status for a GICv3 redistributor is held in a table
in (guest) memory. To achieve reasonable performance, we cache the
pending bit in our struct vgic_irq. The initial pending state must be
read from guest memory upon enabling LPIs for this redistributor.
As we can't access the guest memory while we hold the lpi_list spinlock,
we create a snapshot of the LPI list and iterate over that.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:14:37 +01:00
Andre Przywara 3802411d01 KVM: arm64: vgic-its: Connect LPIs to the VGIC emulation
LPIs are dynamically created (mapped) at guest runtime and their
actual number can be quite high, but is mostly assigned using a very
sparse allocation scheme. So arrays are not an ideal data structure
to hold the information.
We use a spin-lock protected linked list to hold all mapped LPIs,
represented by their struct vgic_irq. This lock is grouped between the
ap_list_lock and the vgic_irq lock in our locking order.
Also we store a pointer to that struct vgic_irq in our struct its_itte,
so we can easily access it.
Eventually we call our new vgic_get_lpi() from vgic_get_irq(), so
the VGIC code gets transparently access to LPIs.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:14:36 +01:00
Andre Przywara 424c33830f KVM: arm64: vgic-its: Implement basic ITS register handlers
Add emulation for some basic MMIO registers used in the ITS emulation.
This includes:
- GITS_{CTLR,TYPER,IIDR}
- ID registers
- GITS_{CBASER,CREADR,CWRITER}
  (which implement the ITS command buffer handling)
- GITS_BASER<n>

Most of the handlers are pretty straight forward, only the CWRITER
handler is a bit more involved by taking the new its_cmd mutex and
then iterating over the command buffer.
The registers holding base addresses and attributes are sanitised before
storing them.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:14:36 +01:00
Andre Przywara 1085fdc68c KVM: arm64: vgic-its: Introduce new KVM ITS device
Introduce a new KVM device that represents an ARM Interrupt Translation
Service (ITS) controller. Since there can be multiple of this per guest,
we can't piggy back on the existing GICv3 distributor device, but create
a new type of KVM device.
On the KVM_CREATE_DEVICE ioctl we allocate and initialize the ITS data
structure and store the pointer in the kvm_device data.
Upon an explicit init ioctl from userland (after having setup the MMIO
address) we register the handlers with the kvm_io_bus framework.
Any reference to an ITS thus has to go via this interface.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:14:35 +01:00
Andre Przywara 59c5ab4098 KVM: arm64: vgic-its: Introduce ITS emulation file with MMIO framework
The ARM GICv3 ITS emulation code goes into a separate file, but needs
to be connected to the GICv3 emulation, of which it is an option.
The ITS MMIO handlers require the respective ITS pointer to be passed in,
so we amend the existing VGIC MMIO framework to let it cope with that.
Also we introduce the basic ITS data structure and initialize it, but
don't return any success yet, as we are not yet ready for the show.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:14:35 +01:00
Andre Przywara 0aa1de5731 KVM: arm64: vgic: Handle ITS related GICv3 redistributor registers
In the GICv3 redistributor there are the PENDBASER and PROPBASER
registers which we did not emulate so far, as they only make sense
when having an ITS. In preparation for that emulate those MMIO
accesses by storing the 64-bit data written into it into a variable
which we later read in the ITS emulation.
We also sanitise the registers, making sure RES0 regions are respected
and checking for valid memory attributes.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:14:35 +01:00
Andre Przywara 5dd4b924e3 KVM: arm/arm64: vgic: Add refcounting for IRQs
In the moment our struct vgic_irq's are statically allocated at guest
creation time. So getting a pointer to an IRQ structure is trivial and
safe. LPIs are more dynamic, they can be mapped and unmapped at any time
during the guest's _runtime_.
In preparation for supporting LPIs we introduce reference counting for
those structures using the kernel's kref infrastructure.
Since private IRQs and SPIs are statically allocated, we avoid actually
refcounting them, since they would never be released anyway.
But we take provisions to increase the refcount when an IRQ gets onto a
VCPU list and decrease it when it gets removed. Also this introduces
vgic_put_irq(), which wraps kref_put and hides the release function from
the callers.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:10:48 +01:00
Andre Przywara 8a39d00670 KVM: kvm_io_bus: Add kvm_io_bus_get_dev() call
The kvm_io_bus framework is a nice place of holding information about
various MMIO regions for kernel emulated devices.
Add a call to retrieve the kvm_io_device structure which is associated
with a certain MMIO address. This avoids to duplicate kvm_io_bus'
knowledge of MMIO regions without having to fake MMIO calls if a user
needs the device a certain MMIO address belongs to.
This will be used by the ITS emulation to get the associated ITS device
when someone triggers an MSI via an ioctl from userspace.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:10:40 +01:00
Andre Przywara 42c8870f90 KVM: arm/arm64: vgic: Check return value for kvm_register_vgic_device
kvm_register_device_ops() can return an error, so lets check its return
value and propagate this up the call chain.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:10:08 +01:00
Andre Przywara 8f6cdc1c2e KVM: arm/arm64: vgic: Move redistributor kvm_io_devices
Logically a GICv3 redistributor is assigned to a (v)CPU, so we should
aim to keep redistributor related variables out of our struct vgic_dist.

Let's start by replacing the redistributor related kvm_io_device array
with two members in our existing struct vgic_cpu, which are naturally
per-VCPU and thus don't require any allocation / freeing.
So apart from the better fit with the redistributor design this saves
some code as well.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:09:40 +01:00
Anna-Maria Gleixner 15d7e3d349 KVM/arm/arm64/vgic-new: Convert to hotplug state machine
Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Andre Przywara <andre.przywara@arm.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Eric Auger <eric.auger@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm@vger.kernel.org
Cc: kvmarm@lists.cs.columbia.edu
Cc: linux-arm-kernel@lists.infradead.org
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153337.900484868@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-15 10:41:43 +02:00
Richard Cochran b3c9950a5c arm/kvm/arch_timer: Convert to hotplug state machine
Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.

Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm@vger.kernel.org
Cc: kvmarm@lists.cs.columbia.edu
Cc: linux-arm-kernel@lists.infradead.org
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153336.634155707@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-15 10:40:27 +02:00
Richard Cochran 42ec50b5f2 arm/kvm/vgic: Convert to hotplug state machine
Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.
The VGIC callback is run after KVM's main callback since it reflects the
makefile order.

Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm@vger.kernel.org
Cc: kvmarm@lists.cs.columbia.edu
Cc: linux-arm-kernel@lists.infradead.org
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153336.546953286@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-15 10:40:26 +02:00
Thomas Gleixner 8c18b2d2d0 virt: Convert kvm hotplug to state machine
Install the callbacks via the state machine. The core won't invoke the
callbacks on already online CPUs.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: kvm@vger.kernel.org
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153335.886159080@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-15 10:40:23 +02:00
Al Viro 506cfba9e7 KVM: don't use anon_inode_getfd() before possible failures
Once anon_inode_getfd() has succeeded, it's impossible to undo
in a clean way and no, sys_close() is not usable in such cases.
Use anon_inode_getfile() and get_unused_fd_flags() to get struct file
and descriptor and do *not* install the file into the descriptor table
until after the last possible failure exit.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-14 19:11:22 +02:00
Paolo Bonzini 7964218c7d Revert "KVM: release anon file in failure path of vm creation"
This reverts commit 77ecc085fed1af1000ca719522977b960aa6da52.

Al Viro colorfully says: "You should *NEVER* use sys_close() on failure
exit paths like that.  Moreover, this kvm_put_kvm() becomes a double-put,
since closing the damn file will drop that reference to kvm.  Please,
revert.  anon_inode_getfd() should be used only when there's no possible
failures past its call".

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-14 19:11:21 +02:00
Liu Shuo 2be5b3f6dc KVM: release anon file in failure path of vm creation
The failure of create debugfs of VM will return directly without release
the anon file. It will leak memory and file descriptors, even through
be not serious.

Signed-off-by: Liu Shuo <shuo.a.liu@intel.com>
Fixes: 536a6f88c4
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-14 19:11:21 +02:00
Jim Mattson 2f1fe81123 KVM: nVMX: Fix memory corruption when using VMCS shadowing
When freeing the nested resources of a vcpu, there is an assumption that
the vcpu's vmcs01 is the current VMCS on the CPU that executes
nested_release_vmcs12(). If this assumption is violated, the vcpu's
vmcs01 may be made active on multiple CPUs at the same time, in
violation of Intel's specification. Moreover, since the vcpu's vmcs01 is
not VMCLEARed on every CPU on which it is active, it can linger in a
CPU's VMCS cache after it has been freed and potentially
repurposed. Subsequent eviction from the CPU's VMCS cache on a capacity
miss can result in memory corruption.

It is not sufficient for vmx_free_vcpu() to call vmx_load_vmcs01(). If
the vcpu in question was last loaded on a different CPU, it must be
migrated to the current CPU before calling vmx_load_vmcs01().

Signed-off-by: Jim Mattson <jmattson@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-14 19:11:20 +02:00
Radim Krčmář c63cf538eb KVM: pass struct kvm to kvm_set_routing_entry
Arch-specific code will use it.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-14 09:03:56 +02:00
Paolo Bonzini add6a0cd1c KVM: MMU: try to fix up page faults before giving up
The vGPU folks would like to trap the first access to a BAR by setting
vm_ops on the VMAs produced by mmap-ing a VFIO device.  The fault handler
then can use remap_pfn_range to place some non-reserved pages in the VMA.

This kind of VM_PFNMAP mapping is not handled by KVM, but follow_pfn
and fixup_user_fault together help supporting it.  The patch also supports
VM_MIXEDMAP vmas where the pfns are not reserved and thus subject to
reference counting.

Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Tested-by: Neo Jia <cjia@nvidia.com>
Reported-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 14:41:26 +02:00
Paolo Bonzini 92176a8ede KVM: MMU: prepare to support mapping of VM_IO and VM_PFNMAP frames
Handle VM_IO like VM_PFNMAP, as is common in the rest of Linux; extract
the formula to convert hva->pfn into a new function, which will soon
gain more capabilities.

Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 14:41:03 +02:00
Marc Zyngier 50926d82fa KVM: arm/arm64: The GIC is dead, long live the GIC
I don't think any single piece of the KVM/ARM code ever generated
as much hatred as the GIC emulation.

It was written by someone who had zero experience in modeling
hardware (me), was riddled with design flaws, should have been
scrapped and rewritten from scratch long before having a remote
chance of reaching mainline, and yet we supported it for a good
three years. No need to mention the names of those who suffered,
the git log is singing their praises.

Thankfully, we now have a much more maintainable implementation,
and we can safely put the grumpy old GIC to rest.

Fellow hackers, please raise your glass in memory of the GIC:

	The GIC is dead, long live the GIC!

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03 23:09:37 +02:00
Xiubo Li caf1ff26e1 kvm: Fix irq route entries exceeding KVM_MAX_IRQ_ROUTES
These days, we experienced one guest crash with 8 cores and 3 disks,
with qemu error logs as bellow:

qemu-system-x86_64: /build/qemu-2.0.0/kvm-all.c:984:
kvm_irqchip_commit_routes: Assertion `ret == 0' failed.

And then we found one patch(bdf026317d) in qemu tree, which said
could fix this bug.

Execute the following script will reproduce the BUG quickly:

irq_affinity.sh
========================================================================

vda_irq_num=25
vdb_irq_num=27
while [ 1 ]
do
    for irq in {1,2,4,8,10,20,40,80}
        do
            echo $irq > /proc/irq/$vda_irq_num/smp_affinity
            echo $irq > /proc/irq/$vdb_irq_num/smp_affinity
            dd if=/dev/vda of=/dev/zero bs=4K count=100 iflag=direct
            dd if=/dev/vdb of=/dev/zero bs=4K count=100 iflag=direct
        done
done
========================================================================

The following qemu log is added in the qemu code and is displayed when
this bug reproduced:

kvm_irqchip_commit_routes: max gsi: 1008, nr_allocated_irq_routes: 1024,
irq_routes->nr: 1024, gsi_count: 1024.

That's to say when irq_routes->nr == 1024, there are 1024 routing entries,
but in the kernel code when routes->nr >= 1024, will just return -EINVAL;

The nr is the number of the routing entries which is in of
[1 ~ KVM_MAX_IRQ_ROUTES], not the index in [0 ~ KVM_MAX_IRQ_ROUTES - 1].

This patch fix the BUG above.

Cc: stable@vger.kernel.org
Signed-off-by: Xiubo Li <lixiubo@cmss.chinamobile.com>
Signed-off-by: Wei Tang <tangwei@cmss.chinamobile.com>
Signed-off-by: Zhang Zhuoyu <zhangzhuoyu@cmss.chinamobile.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-16 09:38:15 +02:00
Paolo Bonzini 557abc40d1 KVM: remove kvm_vcpu_compatible
The new created_vcpus field makes it possible to avoid the race between
irqchip and VCPU creation in a much nicer way; just check under kvm->lock
whether a VCPU has already been created.

We can then remove KVM_APIC_ARCHITECTURE too, because at this point the
symbol is only governing the default definition of kvm_vcpu_compatible.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-16 00:05:00 +02:00
Paolo Bonzini 6c7caebc26 KVM: introduce kvm->created_vcpus
The race between creating the irqchip and the first VCPU is
currently fixed by checking the presence of an irqchip before
updating kvm->online_vcpus, and undoing the whole VCPU creation
if someone created the irqchip in the meanwhile.

Instead, introduce a new field in struct kvm that will count VCPUs
under a mutex, without the atomic access and memory ordering that we
need elsewhere to protect the vcpus array.  This also plugs the race
and is more easily applicable in all similar circumstances.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-16 00:05:00 +02:00
Paolo Bonzini f8c1b85b25 KVM: x86: avoid vmalloc(0) in the KVM_SET_CPUID
This causes an ugly dmesg splat.  Beautified syzkaller testcase:

    #include <unistd.h>
    #include <sys/syscall.h>
    #include <sys/ioctl.h>
    #include <fcntl.h>
    #include <linux/kvm.h>

    long r[8];

    int main()
    {
        struct kvm_irq_routing ir = { 0 };
        r[2] = open("/dev/kvm", O_RDWR);
        r[3] = ioctl(r[2], KVM_CREATE_VM, 0);
        r[4] = ioctl(r[3], KVM_SET_GSI_ROUTING, &ir);
        return 0;
    }

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-06-02 17:38:50 +02:00
Paolo Bonzini c622a3c21e KVM: irqfd: fix NULL pointer dereference in kvm_irq_map_gsi
Found by syzkaller:

    BUG: unable to handle kernel NULL pointer dereference at 0000000000000120
    IP: [<ffffffffa0797202>] kvm_irq_map_gsi+0x12/0x90 [kvm]
    PGD 6f80b067 PUD b6535067 PMD 0
    Oops: 0000 [#1] SMP
    CPU: 3 PID: 4988 Comm: a.out Not tainted 4.4.9-300.fc23.x86_64 #1
    [...]
    Call Trace:
     [<ffffffffa0795f62>] irqfd_update+0x32/0xc0 [kvm]
     [<ffffffffa0796c7c>] kvm_irqfd+0x3dc/0x5b0 [kvm]
     [<ffffffffa07943f4>] kvm_vm_ioctl+0x164/0x6f0 [kvm]
     [<ffffffff81241648>] do_vfs_ioctl+0x298/0x480
     [<ffffffff812418a9>] SyS_ioctl+0x79/0x90
     [<ffffffff817a1062>] tracesys_phase2+0x84/0x89
    Code: b5 71 a7 e0 5b 41 5c 41 5d 5d f3 c3 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 8b 8f 10 2e 00 00 31 c0 48 89 e5 <39> 91 20 01 00 00 76 6a 48 63 d2 48 8b 94 d1 28 01 00 00 48 85
    RIP  [<ffffffffa0797202>] kvm_irq_map_gsi+0x12/0x90 [kvm]
     RSP <ffff8800926cbca8>
    CR2: 0000000000000120

Testcase:

    #include <unistd.h>
    #include <sys/syscall.h>
    #include <string.h>
    #include <stdint.h>
    #include <linux/kvm.h>
    #include <fcntl.h>
    #include <sys/ioctl.h>

    long r[26];

    int main()
    {
        memset(r, -1, sizeof(r));
        r[2] = open("/dev/kvm", 0);
        r[3] = ioctl(r[2], KVM_CREATE_VM, 0);

        struct kvm_irqfd ifd;
        ifd.fd = syscall(SYS_eventfd2, 5, 0);
        ifd.gsi = 3;
        ifd.flags = 2;
        ifd.resamplefd = ifd.fd;
        r[25] = ioctl(r[3], KVM_IRQFD, &ifd);
        return 0;
    }

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-06-02 17:38:50 +02:00