The generic KVM code uses SRCU (sleeping RCU) to protect accesses
to the memslots data structures against updates due to userspace
adding, modifying or removing memory slots. We need to do that too,
both to avoid accessing stale copies of the memslots and to avoid
lockdep warnings. This therefore adds srcu_read_lock/unlock pairs
around code that accesses and uses memslots.
Since the real-mode handlers for H_ENTER, H_REMOVE and H_BULK_REMOVE
need to access the memslots, and we don't want to call the SRCU code
in real mode (since we have no assurance that it would only access
the linear mapping), we hold the SRCU read lock for the VM while
in the guest. This does mean that adding or removing memory slots
while some vcpus are executing in the guest will block for up to
two jiffies. This tradeoff is acceptable since adding/removing
memory slots only happens rarely, while H_ENTER/H_REMOVE/H_BULK_REMOVE
are performance-critical hot paths.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
The current form of DO_KVM macro restricts its use to one call per input
parameter set. This is caused by kvmppc_resume_\intno\()_\srr1 symbol
definition.
Duplicate calls of DO_KVM are required by distinct implementations of
exeption handlers which are delegated at runtime. Use a rare label number
to avoid conflicts with the calling contexts.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
When running on HV aware hosts, we can not trap when the guest sets the FP
bit, so we just let it do so when it wants to, because it has full access to
MSR.
For non-HV aware hosts with an FPU (like 440), we need to also adjust the
shadow MSR though. Otherwise the guest gets an FP unavailable trap even when
it really enabled the FP bit in MSR.
Signed-off-by: Alexander Graf <agraf@suse.de>
Patch to access the debug registers (IACx/DACx) using ONE_REG api
was sent earlier. But that missed the respective documentation.
Also corrected the index number referencing in section 4.69
Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Since we always mark pages as dirty immediately when mapping them read/write
now, there's no need for the dirty flag in our cache.
Signed-off-by: Alexander Graf <agraf@suse.de>
Exit traces are a lot easier to read when you don't have to remember
cryptic numbers for guest exit reasons. Symbolify them in our trace
output.
Signed-off-by: Alexander Graf <agraf@suse.de>
We need to make sure that vcpu->arch.pvr is initialized to a sane value,
so let's just take the host PVR.
Signed-off-by: Alexander Graf <agraf@suse.de>
IAC/DAC are defined as 32 bit while they are 64 bit wide. So ONE_REG
interface is added to set/get them.
Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
This patch adds the watchdog emulation in KVM. The watchdog
emulation is enabled by KVM_ENABLE_CAP(KVM_CAP_PPC_BOOKE_WATCHDOG) ioctl.
The kernel timer are used for watchdog emulation and emulates
h/w watchdog state machine. On watchdog timer expiry, it exit to QEMU
if TCR.WRC is non ZERO. QEMU can reset/shutdown etc depending upon how
it is configured.
Signed-off-by: Liu Yu <yu.liu@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
[bharat.bhushan@freescale.com: reworked patch]
Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
[agraf: adjust to new request framework]
Signed-off-by: Alexander Graf <agraf@suse.de>
Requests may want to tell us that we need to go back into host state,
so add a return value for the checks.
Signed-off-by: Alexander Graf <agraf@suse.de>
Our prepare_to_enter helper wants to be able to return in more circumstances
to the host than only when an interrupt is pending. Broaden the interface a
bit and move even more generic code to the generic helper.
Signed-off-by: Alexander Graf <agraf@suse.de>
We don't need to do anything when mode is EXITING_GUEST_MODE, because
we essentially are outside of guest mode and did everything it asked
us to do by the time we check it.
Signed-off-by: Alexander Graf <agraf@suse.de>
Today, we disable preemption while inside guest context, because we need
to expose to the world that we are not in a preemptible context. However,
during that time we already have interrupts disabled, which would indicate
that we are in a non-preemptible context.
The reason the checks for irqs_disabled() fail for us though is that we
manually control hard IRQs and ignore all the lazy EE framework. Let's
stop doing that. Instead, let's always use lazy EE to indicate when we
want to disable IRQs, but do a special final switch that gets us into
EE disabled, but soft enabled state. That way when we get back out of
guest state, we are immediately ready to process interrupts.
This simplifies the code drastically and reduces the time that we appear
as preempt disabled.
Signed-off-by: Alexander Graf <agraf@suse.de>
When getting out of __vcpu_run, let's be consistent about the state we
return in. We want to always
* have IRQs enabled
* have called kvm_guest_exit before
Signed-off-by: Alexander Graf <agraf@suse.de>
When going out of guest mode, indicate that we are in vcpu->mode. That way
requests from other CPUs don't needlessly need to kick us to process them,
because it'll just happen next time we enter the guest.
Signed-off-by: Alexander Graf <agraf@suse.de>
Now that we use our generic exit helper, we can safely drop our previous
kvm_resched that we used to trigger at the beginning of the exit handler
function.
Signed-off-by: Alexander Graf <agraf@suse.de>
Now that we have very simple MMU Notifier support for e500 in place,
also add the same simple support to book3s. It gets us one step closer
to actual fast support.
Signed-off-by: Alexander Graf <agraf@suse.de>
We need to do the same things when preparing to enter a guest for booke and
book3s_pr cores. Fold the generic code into a generic function that both call.
Signed-off-by: Alexander Graf <agraf@suse.de>
We only call kvmppc_check_requests() when vcpu->requests != 0, so drop
the redundant check in the function itself
Signed-off-by: Alexander Graf <agraf@suse.de>
Without trace points, debugging what exactly is going on inside guest
code can be very tricky. Add a few more trace points at places that
hopefully tell us more when things go wrong.
Signed-off-by: Alexander Graf <agraf@suse.de>
The e500 target has lived without mmu notifiers ever since it got
introduced, but fails for the user space check on them with hugetlbfs.
So in order to get that one working, implement mmu notifiers in a
reasonably dumb fashion and be happy. On embedded hardware, we almost
never end up with mmu notifier calls, since most people don't overcommit.
Signed-off-by: Alexander Graf <agraf@suse.de>
Generic KVM code might want to know whether we are inside guest context
or outside. It also wants to be able to push us out of guest context.
Add support to the BookE code for the generic vcpu->mode field that describes
the above states.
Signed-off-by: Alexander Graf <agraf@suse.de>
We need a central place to check for pending requests in. Add one that
only does the timer check we already do in a different place.
Later, this central function can be extended by more checks.
Signed-off-by: Alexander Graf <agraf@suse.de>
This fixes breakage introduced by the following commit:
commit 6d2d82627f4f1e96a33664ace494fa363e0495cb
Author: Liu Yu-B13201 <Yu.Liu@freescale.com>
Date: Tue Jul 3 05:48:56 2012 +0000
PPC: Don't use hardcoded opcode for ePAPR hcall invocation
when a driver that uses ePAPR hypercalls is built as a module.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
This is printed once for every RMA or HPT region that get
preallocated. If one preallocates hundreds of such regions
(in order to run hundreds of KVM guests), that gets rather
painful, so make it a bit quieter.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Our mapping code assumes that TLB0 entries are always mapped. However, after
calling clear_tlb_refs() this is no longer the case.
Map them dynamically if we find an entry unmapped in TLB0.
Signed-off-by: Alexander Graf <agraf@suse.de>
We're already counting remote TLB flushes in a variable, but don't export
it to user space yet. Do so, so we know what's going on.
Signed-off-by: Alexander Graf <agraf@suse.de>
Semantically, the "SYNC" cap means that we have mmu notifiers available.
Express this in our #ifdef'ery around the feature, so that we can be sure
we don't miss out on ppc targets when they get their implementation.
Signed-off-by: Alexander Graf <agraf@suse.de>
We want to have tracing information on guest exits for booke as well
as book3s. Since most information is identical, use a common trace point.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Stuart Yoder <stuart.yoder@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
And add a new flag definition in kvm_ppc_pvinfo to indicate
whether the host supports the EV_IDLE hcall.
Signed-off-by: Liu Yu <yu.liu@freescale.com>
[stuart.yoder@freescale.com: cleanup,fixes for conditions allowing idle]
Signed-off-by: Stuart Yoder <stuart.yoder@freescale.com>
[agraf: fix typo]
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Liu Yu <yu.liu@freescale.com>
[stuart: factored this out from idle hcall support in host patch]
Signed-off-by: Stuart Yoder <stuart.yoder@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Recent changes (KVM: make processes waiting on vcpu mutex killable)
now requires to check the return value of vcpu_load. This triggered
a warning in s390 specific kvm code. Turns out that we can actually
remove the put/load, since schedule will do the right thing via
the preempt notifiers.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
If we reset a vcpu on INIT, we so far overwrote dr7 as provided by
KVM_SET_GUEST_DEBUG, and we also cleared switch_db_regs unconditionally.
Fix this by saving the dr7 used for guest debugging and calculating the
effective register value as well as switch_db_regs on any potential
change. This will change to focus of the set_guest_debug vendor op to
update_dp_bp_intercept.
Found while trying to stop on start_secondary.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
To emulate level triggered interrupts, add a resample option to
KVM_IRQFD. When specified, a new resamplefd is provided that notifies
the user when the irqchip has been resampled by the VM. This may, for
instance, indicate an EOI. Also in this mode, posting of an interrupt
through an irqfd only asserts the interrupt. On resampling, the
interrupt is automatically de-asserted prior to user notification.
This enables level triggered interrupts to be posted and re-enabled
from vfio with no userspace intervention.
All resampling irqfds can make use of a single irq source ID, so we
reserve a new one for this interface.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Most interrupt are delivered to only one vcpu. Use pre-build tables to
find interrupt destination instead of looping through all vcpus. In case
of logical mode loop only through vcpus in a logical cluster irq is sent
to.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
* queue:
KVM: MMU: Eliminate pointless temporary 'ac'
KVM: MMU: Avoid access/dirty update loop if all is well
KVM: MMU: Eliminate eperm temporary
KVM: MMU: Optimize is_last_gpte()
KVM: MMU: Simplify walk_addr_generic() loop
KVM: MMU: Optimize pte permission checks
KVM: MMU: Update accessed and dirty bits after guest pagetable walk
KVM: MMU: Move gpte_access() out of paging_tmpl.h
KVM: MMU: Optimize gpte_access() slightly
KVM: MMU: Push clean gpte write protection out of gpte_access()
KVM: clarify kvmclock documentation
KVM: make processes waiting on vcpu mutex killable
KVM: SVM: Make use of asm.h
KVM: VMX: Make use of asm.h
KVM: VMX: Make lto-friendly
Signed-off-by: Avi Kivity <avi@redhat.com>
'ac' essentially reconstructs the 'access' variable we already
have, except for the PFERR_PRESENT_MASK and PFERR_RSVD_MASK. As
these are not used by callees, just use 'access' directly.
Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Keep track of accessed/dirty bits; if they are all set, do not
enter the accessed/dirty update loop.
Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
