-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQRTLbB6QfY48x44uB6AXGG7T9hjvgUCXEGhYwAKCRCAXGG7T9hj
vu/qAP4ljV1QwAicTP2IosIpmSojJV4BkkJOs36dgF1u4DscPAEA7YhvTzGYcZr6
7rmBIbGve6Yb24Uh4aL3ir4w+LUvSAg=
=Jm9L
-----END PGP SIGNATURE-----
Merge tag 'for-linus-5.0-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fixes from Juergen Gross:
- Several fixes for the Xen pvcalls drivers (1 fix for the backend and
8 for the frontend).
- A fix for a rather longstanding bug in the Xen sched_clock()
interface which led to weird time jumps when migrating the system.
- A fix for avoiding accesses to x2apic MSRs in Xen PV guests.
* tag 'for-linus-5.0-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen: Fix x86 sched_clock() interface for xen
pvcalls-front: fix potential null dereference
always clear the X2APIC_ENABLE bit for PV guest
pvcalls-front: Avoid get_free_pages(GFP_KERNEL) under spinlock
xen/pvcalls: remove set but not used variable 'intf'
pvcalls-back: set -ENOTCONN in pvcalls_conn_back_read
pvcalls-front: don't return error when the ring is full
pvcalls-front: properly allocate sk
pvcalls-front: don't try to free unallocated rings
pvcalls-front: read all data before closing the connection
Commit f94c8d1169 ("sched/clock, x86/tsc: Rework the x86 'unstable'
sched_clock() interface") broke Xen guest time handling across
migration:
[ 187.249951] Freezing user space processes ... (elapsed 0.001 seconds) done.
[ 187.251137] OOM killer disabled.
[ 187.251137] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
[ 187.252299] suspending xenstore...
[ 187.266987] xen:grant_table: Grant tables using version 1 layout
[18446743811.706476] OOM killer enabled.
[18446743811.706478] Restarting tasks ... done.
[18446743811.720505] Setting capacity to 16777216
Fix that by setting xen_sched_clock_offset at resume time to ensure a
monotonic clock value.
[boris: replaced pr_info() with pr_info_once() in xen_callback_vector()
to avoid printing with incorrect timestamp during resume (as we
haven't re-adjusted the clock yet)]
Fixes: f94c8d1169 ("sched/clock, x86/tsc: Rework the x86 'unstable' sched_clock() interface")
Cc: <stable@vger.kernel.org> # 4.11
Reported-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Tested-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Commit e657fcc clears cpu capability bit instead of using fake cpuid
value, the EXTD should always be off for PV guest without depending
on cpuid value. So remove the cpuid check in xen_read_msr_safe() to
always clear the X2APIC_ENABLE bit.
Signed-off-by: Talons Lee <xin.li@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQRTLbB6QfY48x44uB6AXGG7T9hjvgUCXBvKlAAKCRCAXGG7T9hj
vmIoAP0XpLCE+0Z1hhxcDcJ0hKah1NIniRSIGGr6Af+gxe8F4wEA0Vm55gtEZerU
9mL5S7e2EcuTo93XCIjsxU8uPLGtegQ=
=59wi
-----END PGP SIGNATURE-----
Merge tag 'for-linus-4.21-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen updates from Juergen Gross:
"Xen features and fixes:
- a series to enable KVM guests to be booted by qemu via the Xen PVH
boot entry for speeding up KVM guest tests
- a series for a common driver to be used by Xen PV frontends (right
now drm and sound)
- two other fixes in Xen related code"
* tag 'for-linus-4.21-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
ALSA: xen-front: Use Xen common shared buffer implementation
drm/xen-front: Use Xen common shared buffer implementation
xen: Introduce shared buffer helpers for page directory...
xen/pciback: Check dev_data before using it
kprobes/x86/xen: blacklist non-attachable xen interrupt functions
KVM: x86: Allow Qemu/KVM to use PVH entry point
xen/pvh: Add memory map pointer to hvm_start_info struct
xen/pvh: Move Xen code for getting mem map via hcall out of common file
xen/pvh: Move Xen specific PVH VM initialization out of common file
xen/pvh: Create a new file for Xen specific PVH code
xen/pvh: Move PVH entry code out of Xen specific tree
xen/pvh: Split CONFIG_XEN_PVH into CONFIG_PVH and CONFIG_XEN_PVH
Blacklist symbols in Xen probe-prohibited areas, so that user can see
these prohibited symbols in debugfs.
See also: a50480cb6d.
Signed-off-by: Andrea Righi <righi.andrea@gmail.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
We need to refactor PVH entry code so that support for other hypervisors
like Qemu/KVM can be added more easily.
The original design for PVH entry in Xen guests relies on being able to
obtain the memory map from the hypervisor using a hypercall. When we
extend the PVH entry ABI to support other hypervisors like Qemu/KVM,
a new mechanism will be added that allows the guest to get the memory
map without needing to use hypercalls.
For Xen guests, the hypercall approach will still be supported. In
preparation for adding support for other hypervisors, we can move the
code that uses hypercalls into the Xen specific file. This will allow us
to compile kernels in the future without CONFIG_XEN that are still capable
of being booted as a Qemu/KVM guest via the PVH entry point.
Signed-off-by: Maran Wilson <maran.wilson@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
We need to refactor PVH entry code so that support for other hypervisors
like Qemu/KVM can be added more easily.
This patch moves the small block of code used for initializing Xen PVH
virtual machines into the Xen specific file. This initialization is not
going to be needed for Qemu/KVM guests. Moving it out of the common file
is going to allow us to compile kernels in the future without CONFIG_XEN
that are still capable of being booted as a Qemu/KVM guest via the PVH
entry point.
Signed-off-by: Maran Wilson <maran.wilson@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
We need to refactor PVH entry code so that support for other hypervisors
like Qemu/KVM can be added more easily.
The first step in that direction is to create a new file that will
eventually hold the Xen specific routines.
Signed-off-by: Maran Wilson <maran.wilson@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Once hypervisors other than Xen start using the PVH entry point for
starting VMs, we would like the option of being able to compile PVH entry
capable kernels without enabling CONFIG_XEN and all the code that comes
along with that. To allow that, we are moving the PVH code out of Xen and
into files sitting at a higher level in the tree.
This patch is not introducing any code or functional changes, just moving
files from one location to another.
Signed-off-by: Maran Wilson <maran.wilson@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
In order to pave the way for hypervisors other than Xen to use the PVH
entry point for VMs, we need to factor the PVH entry code into Xen specific
and hypervisor agnostic components. The first step in doing that, is to
create a new config option for PVH entry that can be enabled
independently from CONFIG_XEN.
Signed-off-by: Maran Wilson <maran.wilson@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
There is a guard hole at the beginning of the kernel address space, also
used by hypervisors. It occupies 16 PGD entries.
This reserved range is not defined explicitely, it is calculated relative
to other entities: direct mapping and user space ranges.
The calculation got broken by recent changes of the kernel memory layout:
LDT remap range is now mapped before direct mapping and makes the
calculation invalid.
The breakage leads to crash on Xen dom0 boot[1].
Define the reserved range explicitely. It's part of kernel ABI (hypervisors
expect it to be stable) and must not depend on changes in the rest of
kernel memory layout.
[1] https://lists.xenproject.org/archives/html/xen-devel/2018-11/msg03313.html
Fixes: d52888aa27 ("x86/mm: Move LDT remap out of KASLR region on 5-level paging")
Reported-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: bp@alien8.de
Cc: hpa@zytor.com
Cc: dave.hansen@linux.intel.com
Cc: luto@kernel.org
Cc: peterz@infradead.org
Cc: boris.ostrovsky@oracle.com
Cc: bhe@redhat.com
Cc: linux-mm@kvack.org
Cc: xen-devel@lists.xenproject.org
Link: https://lkml.kernel.org/r/20181130202328.65359-2-kirill.shutemov@linux.intel.com
Go over arch/x86/ and fix common typos in comments,
and a typo in an actual function argument name.
No change in functionality intended.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQRTLbB6QfY48x44uB6AXGG7T9hjvgUCXAOQWAAKCRCAXGG7T9hj
vqqLAQCC+eJNcIEGXm2B5SpadB4v/TKPk+GYRK/zUP0FVPHo3AEAoSTZlmCUUSno
7me8n0sTrd4+ZKMGHvFgAYbpoO90XQM=
=BxP8
-----END PGP SIGNATURE-----
Merge tag 'for-linus-4.20a-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fixes from Juergen Gross:
- A revert of a previous commit as it is no longer necessary and has
shown to cause problems in some memory hotplug cases.
- Some small fixes and a minor cleanup.
- A patch for adding better diagnostic data in a very rare failure
case.
* tag 'for-linus-4.20a-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
pvcalls-front: fixes incorrect error handling
Revert "xen/balloon: Mark unallocated host memory as UNUSABLE"
xen: xlate_mmu: add missing header to fix 'W=1' warning
xen/x86: add diagnostic printout to xen_mc_flush() in case of error
x86/xen: cleanup includes in arch/x86/xen/spinlock.c
This reverts commit b3cf8528bb.
That commit unintentionally broke Xen balloon memory hotplug with
"hotplug_unpopulated" set to 1. As long as "System RAM" resource
got assigned under a new "Unusable memory" resource in IO/Mem tree
any attempt to online this memory would fail due to general kernel
restrictions on having "System RAM" resources as 1st level only.
The original issue that commit has tried to workaround fa564ad963
("x86/PCI: Enable a 64bit BAR on AMD Family 15h (Models 00-1f, 30-3f,
60-7f)") also got amended by the following 03a551734 ("x86/PCI: Move
and shrink AMD 64-bit window to avoid conflict") which made the
original fix to Xen ballooning unnecessary.
Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Failure of an element of a Xen multicall is signalled via a WARN()
only if the kernel is compiled with MC_DEBUG. It is impossible to
know which element failed and why it did so.
Change that by printing the related information even without MC_DEBUG,
even if maybe in some limited form (e.g. without information which
caller produced the failing element).
Move the printing out of the switch statement in order to have the
same information for a single call.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
arch/x86/xen/spinlock.c includes several headers which are not needed.
Remove the #includes.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Pull x86 fixes from Thomas Gleixner:
"A set of x86 fixes:
- Cure the LDT remapping to user space on 5 level paging which ended
up in the KASLR space
- Remove LDT mapping before freeing the LDT pages
- Make NFIT MCE handling more robust
- Unbreak the VSMP build by removing the dependency on paravirt ops
- Support broken PIT emulation on Microsoft hyperV
- Don't trace vmware_sched_clock() to avoid tracer recursion
- Remove -pipe from KBUILD CFLAGS which breaks clang and is also
slower on GCC
- Trivial coding style and typo fixes"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpu/vmware: Do not trace vmware_sched_clock()
x86/vsmp: Remove dependency on pv_irq_ops
x86/ldt: Remove unused variable in map_ldt_struct()
x86/ldt: Unmap PTEs for the slot before freeing LDT pages
x86/mm: Move LDT remap out of KASLR region on 5-level paging
acpi/nfit, x86/mce: Validate a MCE's address before using it
acpi/nfit, x86/mce: Handle only uncorrectable machine checks
x86/build: Remove -pipe from KBUILD_CFLAGS
x86/hyper-v: Fix indentation in hv_do_fast_hypercall16()
Documentation/x86: Fix typo in zero-page.txt
x86/hyper-v: Enable PIT shutdown quirk
clockevents/drivers/i8253: Add support for PIT shutdown quirk
Commit a856531951 ("xen: make xen_qlock_wait() nestable")
introduced a regression for Xen guests running fully virtualized
(HVM or PVH mode). The Xen hypervisor wouldn't return from the poll
hypercall with interrupts disabled in case of an interrupt (for PV
guests it does).
So instead of disabling interrupts in xen_qlock_wait() use a nesting
counter to avoid calling xen_clear_irq_pending() in case
xen_qlock_wait() is nested.
Fixes: a856531951 ("xen: make xen_qlock_wait() nestable")
Cc: stable@vger.kernel.org
Reported-by: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Tested-by: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Juergen Gross <jgross@suse.com>
Commit 9da3f2b740 ("x86/fault: BUG() when uaccess helpers fault on
kernel addresses") introduced a regression for booting Xen PV guests.
Xen PV guests are using __put_user() and __get_user() for accessing the
p2m map (physical to machine frame number map) as accesses might fail
in case of not populated areas of the map.
With above commit using __put_user() and __get_user() for accessing
kernel pages is no longer valid. So replace the Xen hack by adding
appropriate p2m access functions using the default fixup handler.
Fixes: 9da3f2b740 ("x86/fault: BUG() when uaccess helpers fault on kernel addresses")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
On 5-level paging the LDT remap area is placed in the middle of the KASLR
randomization region and it can overlap with the direct mapping, the
vmalloc or the vmap area.
The LDT mapping is per mm, so it cannot be moved into the P4D page table
next to the CPU_ENTRY_AREA without complicating PGD table allocation for
5-level paging.
The 4 PGD slot gap just before the direct mapping is reserved for
hypervisors, so it cannot be used.
Move the direct mapping one slot deeper and use the resulting gap for the
LDT remap area. The resulting layout is the same for 4 and 5 level paging.
[ tglx: Massaged changelog ]
Fixes: f55f0501cb ("x86/pti: Put the LDT in its own PGD if PTI is on")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Cc: bp@alien8.de
Cc: hpa@zytor.com
Cc: dave.hansen@linux.intel.com
Cc: peterz@infradead.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: bhe@redhat.com
Cc: willy@infradead.org
Cc: linux-mm@kvack.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181026122856.66224-2-kirill.shutemov@linux.intel.com
Move remaining definitions and declarations from include/linux/bootmem.h
into include/linux/memblock.h and remove the redundant header.
The includes were replaced with the semantic patch below and then
semi-automated removal of duplicated '#include <linux/memblock.h>
@@
@@
- #include <linux/bootmem.h>
+ #include <linux/memblock.h>
[sfr@canb.auug.org.au: dma-direct: fix up for the removal of linux/bootmem.h]
Link: http://lkml.kernel.org/r/20181002185342.133d1680@canb.auug.org.au
[sfr@canb.auug.org.au: powerpc: fix up for removal of linux/bootmem.h]
Link: http://lkml.kernel.org/r/20181005161406.73ef8727@canb.auug.org.au
[sfr@canb.auug.org.au: x86/kaslr, ACPI/NUMA: fix for linux/bootmem.h removal]
Link: http://lkml.kernel.org/r/20181008190341.5e396491@canb.auug.org.au
Link: http://lkml.kernel.org/r/1536927045-23536-30-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The functions are equivalent, just the later does not require nobootmem
translation layer.
Link: http://lkml.kernel.org/r/1536927045-23536-9-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A Xen PVH guest has no associated qemu device model, so trying to
unplug any emulated devices is making no sense at all.
Bail out early from xen_unplug_emulated_devices() when running as PVH
guest. This will avoid issuing the boot message:
[ 0.000000] Xen Platform PCI: unrecognised magic value
Cc: <stable@vger.kernel.org> # 4.11
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
While booting on an AMD EPYC box the stack canary would detect stack
overflows when using the current PVH early stack size (256). Switch to
using the value defined by BOOT_STACK_SIZE, which prevents the stack
overflow.
Cc: <stable@vger.kernel.org> # 4.11
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
xen_qlock_wait() isn't safe for nested calls due to interrupts. A call
of xen_qlock_kick() might be ignored in case a deeper nesting level
was active right before the call of xen_poll_irq():
CPU 1: CPU 2:
spin_lock(lock1)
spin_lock(lock1)
-> xen_qlock_wait()
-> xen_clear_irq_pending()
Interrupt happens
spin_unlock(lock1)
-> xen_qlock_kick(CPU 2)
spin_lock_irqsave(lock2)
spin_lock_irqsave(lock2)
-> xen_qlock_wait()
-> xen_clear_irq_pending()
clears kick for lock1
-> xen_poll_irq()
spin_unlock_irq_restore(lock2)
-> xen_qlock_kick(CPU 2)
wakes up
spin_unlock_irq_restore(lock2)
IRET
resumes in xen_qlock_wait()
-> xen_poll_irq()
never wakes up
The solution is to disable interrupts in xen_qlock_wait() and not to
poll for the irq in case xen_qlock_wait() is called in nmi context.
Cc: stable@vger.kernel.org
Cc: Waiman.Long@hp.com
Cc: peterz@infradead.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
In the following situation a vcpu waiting for a lock might not be
woken up from xen_poll_irq():
CPU 1: CPU 2: CPU 3:
takes a spinlock
tries to get lock
-> xen_qlock_wait()
frees the lock
-> xen_qlock_kick(cpu2)
-> xen_clear_irq_pending()
takes lock again
tries to get lock
-> *lock = _Q_SLOW_VAL
-> *lock == _Q_SLOW_VAL ?
-> xen_poll_irq()
frees the lock
-> xen_qlock_kick(cpu3)
And cpu 2 will sleep forever.
This can be avoided easily by modifying xen_qlock_wait() to call
xen_poll_irq() only if the related irq was not pending and to call
xen_clear_irq_pending() only if it was pending.
Cc: stable@vger.kernel.org
Cc: Waiman.Long@hp.com
Cc: peterz@infradead.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Pull x86 pti updates from Ingo Molnar:
"The main changes:
- Make the IBPB barrier more strict and add STIBP support (Jiri
Kosina)
- Micro-optimize and clean up the entry code (Andy Lutomirski)
- ... plus misc other fixes"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/speculation: Propagate information about RSB filling mitigation to sysfs
x86/speculation: Enable cross-hyperthread spectre v2 STIBP mitigation
x86/speculation: Apply IBPB more strictly to avoid cross-process data leak
x86/speculation: Add RETPOLINE_AMD support to the inline asm CALL_NOSPEC variant
x86/CPU: Fix unused variable warning when !CONFIG_IA32_EMULATION
x86/pti/64: Remove the SYSCALL64 entry trampoline
x86/entry/64: Use the TSS sp2 slot for SYSCALL/SYSRET scratch space
x86/entry/64: Document idtentry
Pull x86 paravirt updates from Ingo Molnar:
"Two main changes:
- Remove no longer used parts of the paravirt infrastructure and put
large quantities of paravirt ops under a new config option
PARAVIRT_XXL=y, which is selected by XEN_PV only. (Joergen Gross)
- Enable PV spinlocks on Hyperv (Yi Sun)"
* 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/hyperv: Enable PV qspinlock for Hyper-V
x86/hyperv: Add GUEST_IDLE_MSR support
x86/paravirt: Clean up native_patch()
x86/paravirt: Prevent redefinition of SAVE_FLAGS macro
x86/xen: Make xen_reservation_lock static
x86/paravirt: Remove unneeded mmu related paravirt ops bits
x86/paravirt: Move the Xen-only pv_mmu_ops under the PARAVIRT_XXL umbrella
x86/paravirt: Move the pv_irq_ops under the PARAVIRT_XXL umbrella
x86/paravirt: Move the Xen-only pv_cpu_ops under the PARAVIRT_XXL umbrella
x86/paravirt: Move items in pv_info under PARAVIRT_XXL umbrella
x86/paravirt: Introduce new config option PARAVIRT_XXL
x86/paravirt: Remove unused paravirt bits
x86/paravirt: Use a single ops structure
x86/paravirt: Remove clobbers from struct paravirt_patch_site
x86/paravirt: Remove clobbers parameter from paravirt patch functions
x86/paravirt: Make paravirt_patch_call() and paravirt_patch_jmp() static
x86/xen: Add SPDX identifier in arch/x86/xen files
x86/xen: Link platform-pci-unplug.o only if CONFIG_XEN_PVHVM
x86/xen: Move pv specific parts of arch/x86/xen/mmu.c to mmu_pv.c
x86/xen: Move pv irq related functions under CONFIG_XEN_PV umbrella
Pull x86 mm updates from Ingo Molnar:
"Lots of changes in this cycle:
- Lots of CPA (change page attribute) optimizations and related
cleanups (Thomas Gleixner, Peter Zijstra)
- Make lazy TLB mode even lazier (Rik van Riel)
- Fault handler cleanups and improvements (Dave Hansen)
- kdump, vmcore: Enable kdumping encrypted memory with AMD SME
enabled (Lianbo Jiang)
- Clean up VM layout documentation (Baoquan He, Ingo Molnar)
- ... plus misc other fixes and enhancements"
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
x86/stackprotector: Remove the call to boot_init_stack_canary() from cpu_startup_entry()
x86/mm: Kill stray kernel fault handling comment
x86/mm: Do not warn about PCI BIOS W+X mappings
resource: Clean it up a bit
resource: Fix find_next_iomem_res() iteration issue
resource: Include resource end in walk_*() interfaces
x86/kexec: Correct KEXEC_BACKUP_SRC_END off-by-one error
x86/mm: Remove spurious fault pkey check
x86/mm/vsyscall: Consider vsyscall page part of user address space
x86/mm: Add vsyscall address helper
x86/mm: Fix exception table comments
x86/mm: Add clarifying comments for user addr space
x86/mm: Break out user address space handling
x86/mm: Break out kernel address space handling
x86/mm: Clarify hardware vs. software "error_code"
x86/mm/tlb: Make lazy TLB mode lazier
x86/mm/tlb: Add freed_tables element to flush_tlb_info
x86/mm/tlb: Add freed_tables argument to flush_tlb_mm_range
smp,cpumask: introduce on_each_cpu_cond_mask
smp: use __cpumask_set_cpu in on_each_cpu_cond
...
Pull x86 grub2 updates from Ingo Molnar:
"This extends the x86 boot protocol to include an address for the RSDP
table - utilized by Xen currently.
Matching Grub2 patches are pending as well. (Juergen Gross)"
* 'x86-grub2-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/acpi, x86/boot: Take RSDP address for boot params if available
x86/boot: Add ACPI RSDP address to setup_header
x86/xen: Fix boot loader version reported for PVH guests
Pull x86 cpu updates from Ingo Molnar:
"The main changes in this cycle were:
- Add support for the "Dhyana" x86 CPUs by Hygon: these are licensed
based on the AMD Zen architecture, and are built and sold in China,
for domestic datacenter use. The code is pretty close to AMD
support, mostly with a few quirks and enumeration differences. (Pu
Wen)
- Enable CPUID support on Cyrix 6x86/6x86L processors"
* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tools/cpupower: Add Hygon Dhyana support
cpufreq: Add Hygon Dhyana support
ACPI: Add Hygon Dhyana support
x86/xen: Add Hygon Dhyana support to Xen
x86/kvm: Add Hygon Dhyana support to KVM
x86/mce: Add Hygon Dhyana support to the MCA infrastructure
x86/bugs: Add Hygon Dhyana to the respective mitigation machinery
x86/apic: Add Hygon Dhyana support
x86/pci, x86/amd_nb: Add Hygon Dhyana support to PCI and northbridge
x86/amd_nb: Check vendor in AMD-only functions
x86/alternative: Init ideal_nops for Hygon Dhyana
x86/events: Add Hygon Dhyana support to PMU infrastructure
x86/smpboot: Do not use BSP INIT delay and MWAIT to idle on Dhyana
x86/cpu/mtrr: Support TOP_MEM2 and get MTRR number
x86/cpu: Get cache info and setup cache cpumap for Hygon Dhyana
x86/cpu: Create Hygon Dhyana architecture support file
x86/CPU: Change query logic so CPUID is enabled before testing
x86/CPU: Use correct macros for Cyrix calls
Pull x86 build update from Ingo Molnar:
"A small cleanup to x86 Kconfigs"
* 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/kconfig: Remove redundant 'default n' lines from all x86 Kconfig's
The following commit:
d7880812b3 ("idle: Add the stack canary init to cpu_startup_entry()")
... added an x86 specific boot_init_stack_canary() call to the generic
cpu_startup_entry() as a temporary hack, with the intention to remove
the #ifdef CONFIG_X86 later.
More than 5 years later let's finally realize that plan! :-)
While implementing stack protector support for PowerPC, we found
that calling boot_init_stack_canary() is also needed for PowerPC
which uses per task (TLS) stack canary like the X86.
However, calling boot_init_stack_canary() would break architectures
using a global stack canary (ARM, SH, MIPS and XTENSA).
Instead of modifying the #ifdef CONFIG_X86 to an even messier:
#if defined(CONFIG_X86) || defined(CONFIG_PPC)
PowerPC implemented the call to boot_init_stack_canary() in the function
calling cpu_startup_entry().
Let's try the same cleanup on the x86 side as well.
On x86 we have two functions calling cpu_startup_entry():
- start_secondary()
- cpu_bringup_and_idle()
start_secondary() already calls boot_init_stack_canary(), so
it's good, and this patch adds the call to boot_init_stack_canary()
in cpu_bringup_and_idle().
I.e. now x86 catches up to the rest of the world and the ugly init
sequence in init/main.c can be removed from cpu_startup_entry().
As a final benefit we can also remove the <linux/stackprotector.h>
dependency from <linux/sched.h>.
[ mingo: Improved the changelog a bit, added language explaining x86 borkage and sched.h change. ]
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/20181020072649.5B59310483E@pc16082vm.idsi0.si.c-s.fr
Signed-off-by: Ingo Molnar <mingo@kernel.org>
'default n' is the default value for any bool or tristate Kconfig
setting so there is no need to write it explicitly.
Also, since commit:
f467c5640c ("kconfig: only write '# CONFIG_FOO is not set' for visible symbols")
... the Kconfig behavior is the same regardless of 'default n' being present or not:
...
One side effect of (and the main motivation for) this change is making
the following two definitions behave exactly the same:
config FOO
bool
config FOO
bool
default n
With this change, neither of these will generate a
'# CONFIG_FOO is not set' line (assuming FOO isn't selected/implied).
That might make it clearer to people that a bare 'default n' is
redundant.
...
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Juergen Gross <jgross@suse.co>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/20181016134217eucas1p2102984488b89178a865162553369025b%7EeGpI5NlJo0851008510eucas1p2D@eucas1p2.samsung.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The boot loader version reported via sysfs is wrong in case of the
kernel being booted via the Xen PVH boot entry. it should be 2.12
(0x020c), but it is reported to be 2.18 (0x0212).
As the current way to set the version is error prone use the more
readable variant (2 << 8) | 12.
Signed-off-by: Juergen Gross <jgross@suse.com>
Cc: <stable@vger.kernel.org> # 4.12
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: boris.ostrovsky@oracle.com
Cc: bp@alien8.de
Cc: corbet@lwn.net
Cc: linux-doc@vger.kernel.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/20181010061456.22238-2-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=dMl4
-----END PGP SIGNATURE-----
Merge tag 'v4.19-rc6' into for-4.20/block
Merge -rc6 in, for two reasons:
1) Resolve a trivial conflict in the blk-mq-tag.c documentation
2) A few important regression fixes went into upstream directly, so
they aren't in the 4.20 branch.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
* tag 'v4.19-rc6': (780 commits)
Linux 4.19-rc6
MAINTAINERS: fix reference to moved drivers/{misc => auxdisplay}/panel.c
cpufreq: qcom-kryo: Fix section annotations
perf/core: Add sanity check to deal with pinned event failure
xen/blkfront: correct purging of persistent grants
Revert "xen/blkfront: When purging persistent grants, keep them in the buffer"
selftests/powerpc: Fix Makefiles for headers_install change
blk-mq: I/O and timer unplugs are inverted in blktrace
dax: Fix deadlock in dax_lock_mapping_entry()
x86/boot: Fix kexec booting failure in the SEV bit detection code
bcache: add separate workqueue for journal_write to avoid deadlock
drm/amd/display: Fix Edid emulation for linux
drm/amd/display: Fix Vega10 lightup on S3 resume
drm/amdgpu: Fix vce work queue was not cancelled when suspend
Revert "drm/panel: Add device_link from panel device to DRM device"
xen/blkfront: When purging persistent grants, keep them in the buffer
clocksource/drivers/timer-atmel-pit: Properly handle error cases
block: fix deadline elevator drain for zoned block devices
ACPI / hotplug / PCI: Don't scan for non-hotplug bridges if slot is not bridge
drm/syncobj: Don't leak fences when WAIT_FOR_SUBMIT is set
...
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Nothing Xen specific in these headers, which get included from a lot
of code in the kernel. So prune the includes and move them to the
Xen-specific files that actually use them instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQRTLbB6QfY48x44uB6AXGG7T9hjvgUCW6dGhgAKCRCAXGG7T9hj
vs1UAPwPSDmelfUus+P5ndRQZdK/iQWuRgQUe9Gd3RUVTfcQ7AEAljcN4/dSj7SB
hOgRlCp5WB1s5/vFF7z4jc2wtqvOPAk=
=8P9c
-----END PGP SIGNATURE-----
Merge tag 'for-linus-4.19d-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Juergen writes:
"xen:
Two small fixes for xen drivers."
* tag 'for-linus-4.19d-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen: issue warning message when out of grant maptrack entries
xen/x86/vpmu: Zero struct pt_regs before calling into sample handling code
We met a kernel panic when enabling earlycon, which is due to the fixmap
address of earlycon is not statically setup.
Currently the static fixmap setup in head_64.S only covers 2M virtual
address space, while it actually could be in 4M space with different
kernel configurations, e.g. when VSYSCALL emulation is disabled.
So increase the static space to 4M for now by defining FIXMAP_PMD_NUM to 2,
and add a build time check to ensure that the fixmap is covered by the
initial static page tables.
Fixes: 1ad83c858c ("x86_64,vsyscall: Make vsyscall emulation configurable")
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: kernel test robot <rong.a.chen@intel.com>
Reviewed-by: Juergen Gross <jgross@suse.com> (Xen parts)
Cc: H Peter Anvin <hpa@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andy Lutomirsky <luto@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180920025828.23699-1-feng.tang@intel.com
Otherwise we may leak kernel stack for events that sample user
registers.
Reported-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: stable@vger.kernel.org
In the non-trampoline SYSCALL64 path, a percpu variable is used to
temporarily store the user RSP value.
Instead of a separate variable, use the otherwise unused sp2 slot in the
TSS. This will improve cache locality, as the sp1 slot is already used in
the same code to find the kernel stack. It will also simplify a future
change to make the non-trampoline path work in PTI mode.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/08e769a0023dbad4bac6f34f3631dbaf8ad59f4f.1536015544.git.luto@kernel.org
All functions in arch/x86/xen/irq.c and arch/x86/xen/xen-asm*.S are
specific to PV guests. Include them in the kernel with CONFIG_XEN_PV only.
Make the PV specific code in arch/x86/entry/entry_*.S dependent on
CONFIG_XEN_PV instead of CONFIG_XEN.
The HVM specific code should depend on CONFIG_XEN_PVHVM.
While at it reformat the Makefile to make it more readable.
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: xen-devel@lists.xenproject.org
Cc: virtualization@lists.linux-foundation.org
Cc: akataria@vmware.com
Cc: rusty@rustcorp.com.au
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/20180828074026.820-2-jgross@suse.com
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQRTLbB6QfY48x44uB6AXGG7T9hjvgUCW4lM6AAKCRCAXGG7T9hj
vs8AAQDysFccg97UdopW3B7yklIaRqkfEIAsxe65f191MXsH2AEAp5SKxZqRPqBP
a9WHDj8ShB3BhZ/IxpdO9Y59U3Jo4wA=
=Gt4c
-----END PGP SIGNATURE-----
Merge tag 'for-linus-4.19b-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fixes from Juergen Gross:
- minor cleanup avoiding a warning when building with new gcc
- a patch to add a new sysfs node for Xen frontend/backend drivers to
make it easier to obtain the state of a pv device
- two fixes for 32-bit pv-guests to avoid intermediate L1TF vulnerable
PTEs
* tag 'for-linus-4.19b-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
x86/xen: remove redundant variable save_pud
xen: export device state to sysfs
x86/pae: use 64 bit atomic xchg function in native_ptep_get_and_clear
x86/xen: don't write ptes directly in 32-bit PV guests
Variable save_pud is being assigned but is never used hence it is
redundant and can be removed.
Cleans up clang warning:
variable 'save_pud' set but not used [-Wunused-but-set-variable]
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
In some cases 32-bit PAE PV guests still write PTEs directly instead of
using hypercalls. This is especially bad when clearing a PTE as this is
done via 32-bit writes which will produce intermediate L1TF attackable
PTEs.
Change the code to use hypercalls instead.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Merge fixes for missing TLB shootdowns.
This fixes a couple of cases that involved us possibly freeing page
table structures before the required TLB shootdown had been done.
There are a few cleanup patches to make the code easier to follow, and
to avoid some of the more problematic cases entirely when not necessary.
To make this easier for backports, it undoes the recent lazy TLB
patches, because the cleanups and fixes are more important, and Rik is
ok with re-doing them later when things have calmed down.
The missing TLB flush was only delayed, and the wrong ordering only
happened under memory pressure (and in theory under a couple of other
fairly theoretical situations), so this may have been all very unlikely
to have hit people in practice.
But getting the TLB shootdown wrong is _so_ hard to debug and see that I
consider this a crticial fix.
Many thanks to Jann Horn for having debugged this.
* tlb-fixes:
x86/mm: Only use tlb_remove_table() for paravirt
mm: mmu_notifier fix for tlb_end_vma
mm/tlb, x86/mm: Support invalidating TLB caches for RCU_TABLE_FREE
mm/tlb: Remove tlb_remove_table() non-concurrent condition
mm: move tlb_table_flush to tlb_flush_mmu_free
x86/mm/tlb: Revert the recent lazy TLB patches
If we don't use paravirt; don't play unnecessary and complicated games
to free page-tables.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 7b25b9cb0d ("x86/xen/time: Initialize pv xen time in
init_hypervisor_platform()") moved the mapping of the shared info area
before pagetable_init(). This breaks booting as 32-bit PV guest as the
use of set_fixmap isn't possible at this time on 32-bit.
This can be worked around by populating the needed PMD on 32-bit
kernel earlier.
In order not to reimplement populate_extra_pte() using extend_brk()
for allocating new page tables extend alloc_low_pages() to do that in
case the early page table pool is not yet available.
Fixes: 7b25b9cb0d ("x86/xen/time: Initialize pv xen time in init_hypervisor_platform()")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
xen_auto_xlated_memory_setup() is a leftover from PVH V1. Remove it.
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
As the sequence of invocations matters, add "tty" only after "hvc" when
a VGA console is available (which is often the case for Dom0, but hardly
ever for DomU).
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Its only caller is __init, so to avoid section mismatch warnings when a
compiler decides to not inline the function marke this function so as
well. Take the opportunity and also make the function actually use its
argument: The sole caller passes in zero anyway.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQRTLbB6QfY48x44uB6AXGG7T9hjvgUCW3LkCgAKCRCAXGG7T9hj
vtyfAQDTMUqfBlpz9XqFyTBTFRkP3aVtnEeE7BijYec+RXPOxwEAsiXwZPsmW/AN
up+NEHqPvMOcZC8zJZ9THCiBgOxligY=
=F51X
-----END PGP SIGNATURE-----
Merge tag 'for-linus-4.19-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen updates from Juergen Gross:
- add dma-buf functionality to Xen grant table handling
- fix for booting the kernel as Xen PVH dom0
- fix for booting the kernel as a Xen PV guest with
CONFIG_DEBUG_VIRTUAL enabled
- other minor performance and style fixes
* tag 'for-linus-4.19-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/balloon: fix balloon initialization for PVH Dom0
xen: don't use privcmd_call() from xen_mc_flush()
xen/pv: Call get_cpu_address_sizes to set x86_virt/phys_bits
xen/biomerge: Use true and false for boolean values
xen/gntdev: don't dereference a null gntdev_dmabuf on allocation failure
xen/spinlock: Don't use pvqspinlock if only 1 vCPU
xen/gntdev: Implement dma-buf import functionality
xen/gntdev: Implement dma-buf export functionality
xen/gntdev: Add initial support for dma-buf UAPI
xen/gntdev: Make private routines/structures accessible
xen/gntdev: Allow mappings for DMA buffers
xen/grant-table: Allow allocating buffers suitable for DMA
xen/balloon: Share common memory reservation routines
xen/grant-table: Make set/clear page private code shared
Merge L1 Terminal Fault fixes from Thomas Gleixner:
"L1TF, aka L1 Terminal Fault, is yet another speculative hardware
engineering trainwreck. It's a hardware vulnerability which allows
unprivileged speculative access to data which is available in the
Level 1 Data Cache when the page table entry controlling the virtual
address, which is used for the access, has the Present bit cleared or
other reserved bits set.
If an instruction accesses a virtual address for which the relevant
page table entry (PTE) has the Present bit cleared or other reserved
bits set, then speculative execution ignores the invalid PTE and loads
the referenced data if it is present in the Level 1 Data Cache, as if
the page referenced by the address bits in the PTE was still present
and accessible.
While this is a purely speculative mechanism and the instruction will
raise a page fault when it is retired eventually, the pure act of
loading the data and making it available to other speculative
instructions opens up the opportunity for side channel attacks to
unprivileged malicious code, similar to the Meltdown attack.
While Meltdown breaks the user space to kernel space protection, L1TF
allows to attack any physical memory address in the system and the
attack works across all protection domains. It allows an attack of SGX
and also works from inside virtual machines because the speculation
bypasses the extended page table (EPT) protection mechanism.
The assoicated CVEs are: CVE-2018-3615, CVE-2018-3620, CVE-2018-3646
The mitigations provided by this pull request include:
- Host side protection by inverting the upper address bits of a non
present page table entry so the entry points to uncacheable memory.
- Hypervisor protection by flushing L1 Data Cache on VMENTER.
- SMT (HyperThreading) control knobs, which allow to 'turn off' SMT
by offlining the sibling CPU threads. The knobs are available on
the kernel command line and at runtime via sysfs
- Control knobs for the hypervisor mitigation, related to L1D flush
and SMT control. The knobs are available on the kernel command line
and at runtime via sysfs
- Extensive documentation about L1TF including various degrees of
mitigations.
Thanks to all people who have contributed to this in various ways -
patches, review, testing, backporting - and the fruitful, sometimes
heated, but at the end constructive discussions.
There is work in progress to provide other forms of mitigations, which
might be less horrible performance wise for a particular kind of
workloads, but this is not yet ready for consumption due to their
complexity and limitations"
* 'l1tf-final' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (75 commits)
x86/microcode: Allow late microcode loading with SMT disabled
tools headers: Synchronise x86 cpufeatures.h for L1TF additions
x86/mm/kmmio: Make the tracer robust against L1TF
x86/mm/pat: Make set_memory_np() L1TF safe
x86/speculation/l1tf: Make pmd/pud_mknotpresent() invert
x86/speculation/l1tf: Invert all not present mappings
cpu/hotplug: Fix SMT supported evaluation
KVM: VMX: Tell the nested hypervisor to skip L1D flush on vmentry
x86/speculation: Use ARCH_CAPABILITIES to skip L1D flush on vmentry
x86/speculation: Simplify sysfs report of VMX L1TF vulnerability
Documentation/l1tf: Remove Yonah processors from not vulnerable list
x86/KVM/VMX: Don't set l1tf_flush_l1d from vmx_handle_external_intr()
x86/irq: Let interrupt handlers set kvm_cpu_l1tf_flush_l1d
x86: Don't include linux/irq.h from asm/hardirq.h
x86/KVM/VMX: Introduce per-host-cpu analogue of l1tf_flush_l1d
x86/irq: Demote irq_cpustat_t::__softirq_pending to u16
x86/KVM/VMX: Move the l1tf_flush_l1d test to vmx_l1d_flush()
x86/KVM/VMX: Replace 'vmx_l1d_flush_always' with 'vmx_l1d_flush_cond'
x86/KVM/VMX: Don't set l1tf_flush_l1d to true from vmx_l1d_flush()
cpu/hotplug: detect SMT disabled by BIOS
...
Using privcmd_call() for a singleton multicall seems to be wrong, as
privcmd_call() is using stac()/clac() to enable hypervisor access to
Linux user space.
Even if currently not a problem (pv domains can't use SMAP while HVM
and PVH domains can't use multicalls) things might change when
PVH dom0 support is added to the kernel.
Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Commit d94a155c59 ("x86/cpu: Prevent cpuinfo_x86::x86_phys_bits
adjustment corruption") has moved the query and calculation of the
x86_virt_bits and x86_phys_bits fields of the cpuinfo_x86 struct
from the get_cpu_cap function to a new function named
get_cpu_address_sizes.
One of the call sites related to Xen PV VMs was unfortunately missed
in the aforementioned commit. This prevents successful boot-up of
kernel versions 4.17 and up in Xen PV VMs if CONFIG_DEBUG_VIRTUAL
is enabled, due to the following code path:
enlighten_pv.c::xen_start_kernel
mmu_pv.c::xen_reserve_special_pages
page.h::__pa
physaddr.c::__phys_addr
physaddr.h::phys_addr_valid
phys_addr_valid uses boot_cpu_data.x86_phys_bits to validate physical
addresses. boot_cpu_data.x86_phys_bits is no longer populated before
the call to xen_reserve_special_pages due to the aforementioned commit
though, so the validation performed by phys_addr_valid fails, which
causes __phys_addr to trigger a BUG, preventing boot-up.
Signed-off-by: M. Vefa Bicakci <m.v.b@runbox.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: xen-devel@lists.xenproject.org
Cc: x86@kernel.org
Cc: stable@vger.kernel.org # for v4.17 and up
Fixes: d94a155c59 ("x86/cpu: Prevent cpuinfo_x86::x86_phys_bits adjustment corruption")
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
The next patch in this series will have to make the definition of
irq_cpustat_t available to entering_irq().
Inclusion of asm/hardirq.h into asm/apic.h would cause circular header
dependencies like
asm/smp.h
asm/apic.h
asm/hardirq.h
linux/irq.h
linux/topology.h
linux/smp.h
asm/smp.h
or
linux/gfp.h
linux/mmzone.h
asm/mmzone.h
asm/mmzone_64.h
asm/smp.h
asm/apic.h
asm/hardirq.h
linux/irq.h
linux/irqdesc.h
linux/kobject.h
linux/sysfs.h
linux/kernfs.h
linux/idr.h
linux/gfp.h
and others.
This causes compilation errors because of the header guards becoming
effective in the second inclusion: symbols/macros that had been defined
before wouldn't be available to intermediate headers in the #include chain
anymore.
A possible workaround would be to move the definition of irq_cpustat_t
into its own header and include that from both, asm/hardirq.h and
asm/apic.h.
However, this wouldn't solve the real problem, namely asm/harirq.h
unnecessarily pulling in all the linux/irq.h cruft: nothing in
asm/hardirq.h itself requires it. Also, note that there are some other
archs, like e.g. arm64, which don't have that #include in their
asm/hardirq.h.
Remove the linux/irq.h #include from x86' asm/hardirq.h.
Fix resulting compilation errors by adding appropriate #includes to *.c
files as needed.
Note that some of these *.c files could be cleaned up a bit wrt. to their
set of #includes, but that should better be done from separate patches, if
at all.
Signed-off-by: Nicolai Stange <nstange@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
On a VM with only 1 vCPU, the locking fast paths will always be
successful. In this case, there is no need to use the the PV qspinlock
code which has higher overhead on the unlock side than the native
qspinlock code.
The xen_pvspin veriable is also turned off in this 1 vCPU case to
eliminate unneeded pvqspinlock initialization in xen_init_lock_cpu()
which is run after xen_init_spinlocks().
Signed-off-by: Waiman Long <longman@redhat.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQRTLbB6QfY48x44uB6AXGG7T9hjvgUCW0myzgAKCRCAXGG7T9hj
vrEhAP9/WLKMyJy7dCkw02+euGS4baTFS38vJMOzmhudyRCkJQD8Dvuu7hoA0hoX
Aqoi/KH/DQUOHuSEelKOSlnQ4oQ+wQw=
=/N+q
-----END PGP SIGNATURE-----
Merge tag 'for-linus-4.18-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fixes from Juergen Gross:
"Two related fixes for a boot failure of Xen PV guests"
* tag 'for-linus-4.18-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen: setup pv irq ops vector earlier
xen: remove global bit from __default_kernel_pte_mask for pv guests
Setting pv_irq_ops for Xen PV domains should be done as early as
possible in order to support e.g. very early printk() usage.
The same applies to xen_vcpu_info_reset(0), as it is needed for the
pv irq ops.
Move the call of xen_setup_machphys_mapping() after initializing the
pv functions as it contains a WARN_ON(), too.
Remove the no longer necessary conditional in xen_init_irq_ops()
from PVH V1 times to make clear this is a PV only function.
Cc: <stable@vger.kernel.org> # 4.14
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
When removing the global bit from __supported_pte_mask do the same for
__default_kernel_pte_mask in order to avoid the WARN_ONCE() in
check_pgprot() when setting a kernel pte before having called
init_mem_mapping().
Cc: <stable@vger.kernel.org> # 4.17
Reported-by: Michael Young <m.a.young@durham.ac.uk>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Pull x86 fixes from Thomas Gleixner:
"A set of fixes for x86:
- Make Xen PV guest deal with speculative store bypass correctly
- Address more fallout from the 5-Level pagetable handling. Undo an
__initdata annotation to avoid section mismatch and malfunction
when post init code would touch the freed variable.
- Handle exception fixup in math_error() before calling notify_die().
The reverse call order incorrectly triggers notify_die() listeners
for soemthing which is handled correctly at the site which issues
the floating point instruction.
- Fix an off by one in the LLC topology calculation on AMD
- Handle non standard memory block sizes gracefully un UV platforms
- Plug a memory leak in the microcode loader
- Sanitize the purgatory build magic
- Add the x86 specific device tree bindings directory to the x86
MAINTAINER file patterns"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Fix 'no5lvl' handling
Revert "x86/mm: Mark __pgtable_l5_enabled __initdata"
x86/CPU/AMD: Fix LLC ID bit-shift calculation
MAINTAINERS: Add file patterns for x86 device tree bindings
x86/microcode/intel: Fix memleak in save_microcode_patch()
x86/platform/UV: Add kernel parameter to set memory block size
x86/platform/UV: Use new set memory block size function
x86/platform/UV: Add adjustable set memory block size function
x86/build: Remove unnecessary preparation for purgatory
Revert "kexec/purgatory: Add clean-up for purgatory directory"
x86/xen: Add call of speculative_store_bypass_ht_init() to PV paths
x86: Call fixup_exception() before notify_die() in math_error()
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQRTLbB6QfY48x44uB6AXGG7T9hjvgUCWy0LEwAKCRCAXGG7T9hj
vgbIAQD0rMLgEvvpdyvYpaHEBj9w40olCNh8ur49FRSPAdfh/QEArOtqO0OM+6ju
RGmsIr/A4C8L80HPN4u/iIWXqJDbJwA=
=DnvK
-----END PGP SIGNATURE-----
Merge tag 'for-linus-4.18-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fixes from Juergen Gross:
"This contains the following fixes/cleanups:
- the removal of a BUG_ON() which wasn't necessary and which could
trigger now due to a recent change
- a correction of a long standing bug happening very rarely in Xen
dom0 when a hypercall buffer from user land was not accessible by
the hypervisor for very short periods of time due to e.g. page
migration or compaction
- usage of EXPORT_SYMBOL_GPL() instead of EXPORT_SYMBOL() in a
Xen-related driver (no breakage possible as using those symbols
without others already exported via EXPORT-SYMBOL_GPL() wouldn't
make any sense)
- a simplification for Xen PVH or Xen ARM guests
- some additional error handling for callers of xenbus_printf()"
* tag 'for-linus-4.18-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen: Remove unnecessary BUG_ON from __unbind_from_irq()
xen: add new hypercall buffer mapping device
xen/scsiback: add error handling for xenbus_printf
scsi: xen-scsifront: add error handling for xenbus_printf
xen/grant-table: Export gnttab_{alloc|free}_pages as GPL
xen: add error handling for xenbus_printf
xen: share start flags between PV and PVH
Commit:
1f50ddb4f4 ("x86/speculation: Handle HT correctly on AMD")
... added speculative_store_bypass_ht_init() to the per-CPU initialization sequence.
speculative_store_bypass_ht_init() needs to be called on each CPU for
PV guests, too.
Reported-by: Brian Woods <brian.woods@amd.com>
Tested-by: Brian Woods <brian.woods@amd.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Cc: <stable@vger.kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: boris.ostrovsky@oracle.com
Cc: xen-devel@lists.xenproject.org
Fixes: 1f50ddb4f4 ("x86/speculation: Handle HT correctly on AMD")
Link: https://lore.kernel.org/lkml/20180621084331.21228-1-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Use a global variable to store the start flags for both PV and PVH.
This allows the xen_initial_domain macro to work properly on PVH.
Note that ARM is also switched to use the new variable.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQRTLbB6QfY48x44uB6AXGG7T9hjvgUCWxoCWAAKCRCAXGG7T9hj
vvDrAQCR6Js8PWjU8HnaYV/AKYGJ/JANLUSKhK/piel+ed7c7AD/T2XV7m0WI+Rb
p+dwBd7NLoVokF4SQHvvWgQJLSW7qAA=
=BnsW
-----END PGP SIGNATURE-----
Merge tag 'for-linus-4.18-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen updates from Juergen Gross:
"This contains some minor code cleanups (fixing return types of
functions), some fixes for Linux running as Xen PVH guest, and adding
of a new guest resource mapping feature for Xen tools"
* tag 'for-linus-4.18-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/PVH: Make GDT selectors PVH-specific
xen/PVH: Set up GS segment for stack canary
xen/store: do not store local values in xen_start_info
xen-netfront: fix xennet_start_xmit()'s return type
xen/privcmd: add IOCTL_PRIVCMD_MMAP_RESOURCE
xen: Change return type to vm_fault_t
Pull EFI updates from Ingo Molnar:
- decode x86 CPER data (Yazen Ghannam)
- ignore unrealistically large option ROMs (Hans de Goede)
- initialize UEFI secure boot state during Xen dom0 boot (Daniel Kiper)
- additional minor tweaks and fixes.
* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi/capsule-loader: Don't output reset log when reset flags are not set
efi/x86: Ignore unrealistically large option ROMs
efi/x86: Fold __setup_efi_pci32() and __setup_efi_pci64() into one function
efi: Align efi_pci_io_protocol typedefs to type naming convention
efi/libstub/tpm: Make function efi_retrieve_tpm2_eventlog_1_2() static
efi: Decode IA32/X64 Context Info structure
efi: Decode IA32/X64 MS Check structure
efi: Decode additional IA32/X64 Bus Check fields
efi: Decode IA32/X64 Cache, TLB, and Bus Check structures
efi: Decode UEFI-defined IA32/X64 Error Structure GUIDs
efi: Decode IA32/X64 Processor Error Info Structure
efi: Decode IA32/X64 Processor Error Section
efi: Fix IA32/X64 Processor Error Record definition
efi/cper: Remove the INDENT_SP silliness
x86/xen/efi: Initialize UEFI secure boot state during dom0 boot
We don't need to share PVH GDT layout with other GDTs, especially
since we now have a PVH-speciific entry (for stack canary segment).
Define PVH's own selectors.
(As a side effect of this change we are also fixing improper
reference to __KERNEL_CS)
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
We are making calls to C code (e.g. xen_prepare_pvh()) which may use
stack canary (stored in GS segment).
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
The x86 platform operations are fairly isolated, so it's easy to change
them from using timespec to timespec64. It has been checked that all the
users and callers are safe, and there is only one critical function that is
broken beyond 2106:
pvclock_read_wallclock() uses a 32-bit number of seconds since the epoch
to communicate the boot time between host and guest in a virtual
environment. This will work until 2106, but fixing this is outside the
scope of this change, Add a comment at least.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Radim Krčmář <rkrcmar@redhat.com>
Acked-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: jailhouse-dev@googlegroups.com
Cc: Borislav Petkov <bp@suse.de>
Cc: kvm@vger.kernel.org
Cc: y2038@lists.linaro.org
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: xen-devel@lists.xenproject.org
Cc: John Stultz <john.stultz@linaro.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Joao Martins <joao.m.martins@oracle.com>
Link: https://lkml.kernel.org/r/20180427201435.3194219-1-arnd@arndb.de
a field event. This is increasingly important for the histogram trigger
work that is being extended.
While auditing trace events, I found that a couple of the xen events
were used as just marking that a function was called, by creating
a static array of size zero. This can play havoc with the tracing
features if these events are used, because a zero size of a static
array is denoted as a special nul terminated dynamic array (this is
what the trace_marker code uses). But since the xen events have no
size, they are not nul terminated, and unexpected results may occur.
As trace events were never intended on being a marker to denote
that a function was hit or not, especially since function tracing
and kprobes can trivially do the same, the best course of action is
to simply remove these events.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCWvtgDhQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qtY0AQC2HSSRkP5GVL1/c1Xoxl202O1tQ9Dp
G08oci4bfcRCIAEA8ATc+1LZPGQUvd0ucrD4FiJnfpYUHrCTvvRsz4d9LQQ=
=HUQR
-----END PGP SIGNATURE-----
Merge tag 'trace-v4.17-rc4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fix from Steven Rostedt:
"Some of the ftrace internal events use a zero for a data size of a
field event. This is increasingly important for the histogram trigger
work that is being extended.
While auditing trace events, I found that a couple of the xen events
were used as just marking that a function was called, by creating a
static array of size zero. This can play havoc with the tracing
features if these events are used, because a zero size of a static
array is denoted as a special nul terminated dynamic array (this is
what the trace_marker code uses). But since the xen events have no
size, they are not nul terminated, and unexpected results may occur.
As trace events were never intended on being a marker to denote that a
function was hit or not, especially since function tracing and kprobes
can trivially do the same, the best course of action is to simply
remove these events"
* tag 'trace-v4.17-rc4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing/x86/xen: Remove zero data size trace events trace_xen_mmu_flush_tlb{_all}
Doing an audit of trace events, I discovered two trace events in the xen
subsystem that use a hack to create zero data size trace events. This is not
what trace events are for. Trace events add memory footprint overhead, and
if all you need to do is see if a function is hit or not, simply make that
function noinline and use function tracer filtering.
Worse yet, the hack used was:
__array(char, x, 0)
Which creates a static string of zero in length. There's assumptions about
such constructs in ftrace that this is a dynamic string that is nul
terminated. This is not the case with these tracepoints and can cause
problems in various parts of ftrace.
Nuke the trace events!
Link: http://lkml.kernel.org/r/20180509144605.5a220327@gandalf.local.home
Cc: stable@vger.kernel.org
Fixes: 95a7d76897 ("xen/mmu: Use Xen specific TLB flush instead of the generic one.")
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
My recent Xen patch series introduces a new HYPERVISOR_memory_op to
support direct priv-mapping of certain guest resources (such as ioreq
pages, used by emulators) by a tools domain, rather than having to access
such resources via the guest P2M.
This patch adds the necessary infrastructure to the privcmd driver and
Xen MMU code to support direct resource mapping.
NOTE: The adjustment in the MMU code is partially cosmetic. Xen will now
allow a PV tools domain to map guest pages either by GFN or MFN, thus
the term 'mfn' has been swapped for 'pfn' in the lower layers of the
remap code.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Initialize UEFI secure boot state during dom0 boot. Otherwise the kernel
may not even know that it runs on secure boot enabled platform.
Note that part of drivers/firmware/efi/libstub/secureboot.c is duplicated
by this patch, only in this case, it runs in the context of the kernel
proper rather than UEFI boot context. The reason for the duplication is
that maintaining the original code to run correctly on ARM/arm64 as well
as on all the quirky x86 firmware we support is enough of a burden as it
is, and adding the x86/Xen execution context to that mix just so we can
reuse a single routine just isn't worth it.
[ardb: explain rationale for code duplication]
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180504060003.19618-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQRTLbB6QfY48x44uB6AXGG7T9hjvgUCWvV2WQAKCRCAXGG7T9hj
vvV1AQD/mqwRavel82e8JiMosoqrpZWwZ4uK2m7DhhIGhdyuegEAjmqzkjYSInrA
0A7FeFH2Wl1nYiKBl8ppvAd2GOkbbws=
=kcKL
-----END PGP SIGNATURE-----
Merge tag 'for-linus-4.17-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fix from Juergen Gross:
"One fix for the kernel running as a fully virtualized guest using PV
drivers on old Xen hypervisor versions"
* tag 'for-linus-4.17-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
x86/xen: Reset VCPU0 info pointer after shared_info remap
This patch fixes crashes during boot for HVM guests on older (pre HVM
vector callback) Xen versions. Without this, current kernels will always
fail to boot on those Xen versions.
Sample stack trace:
BUG: unable to handle kernel paging request at ffffffffff200000
IP: __xen_evtchn_do_upcall+0x1e/0x80
PGD 1e0e067 P4D 1e0e067 PUD 1e10067 PMD 235c067 PTE 0
Oops: 0002 [#1] SMP PTI
Modules linked in:
CPU: 0 PID: 512 Comm: kworker/u2:0 Not tainted 4.14.33-52.13.amzn1.x86_64 #1
Hardware name: Xen HVM domU, BIOS 3.4.3.amazon 11/11/2016
task: ffff88002531d700 task.stack: ffffc90000480000
RIP: 0010:__xen_evtchn_do_upcall+0x1e/0x80
RSP: 0000:ffff880025403ef0 EFLAGS: 00010046
RAX: ffffffff813cc760 RBX: ffffffffff200000 RCX: ffffc90000483ef0
RDX: ffff880020540a00 RSI: ffff880023c78000 RDI: 000000000000001c
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff880025403f5c R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff880025400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffff200000 CR3: 0000000001e0a000 CR4: 00000000000006f0
Call Trace:
<IRQ>
do_hvm_evtchn_intr+0xa/0x10
__handle_irq_event_percpu+0x43/0x1a0
handle_irq_event_percpu+0x20/0x50
handle_irq_event+0x39/0x60
handle_fasteoi_irq+0x80/0x140
handle_irq+0xaf/0x120
do_IRQ+0x41/0xd0
common_interrupt+0x7d/0x7d
</IRQ>
During boot, the HYPERVISOR_shared_info page gets remapped to make it work
with KASLR. This means that any pointer derived from it needs to be
adjusted.
The only value that this applies to is the vcpu_info pointer for VCPU 0.
For PV and HVM with the callback vector feature, this gets done via the
smp_ops prepare_boot_cpu callback. Older Xen versions do not support the
HVM callback vector, so there is no Xen-specific smp_ops set up in that
scenario. So, the vcpu_info pointer for VCPU 0 never gets set to the proper
value, and the first reference of it will be bad. Fix this by resetting it
immediately after the remap.
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Reviewed-by: Eduardo Valentin <eduval@amazon.com>
Reviewed-by: Alakesh Haloi <alakeshh@amazon.com>
Reviewed-by: Vallish Vaidyeshwara <vallish@amazon.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: xen-devel@lists.xenproject.org
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQRTLbB6QfY48x44uB6AXGG7T9hjvgUCWuwoogAKCRCAXGG7T9hj
vr23AP4vj3yoii3mihZYjDahwyE+3fILUWECl/d/cMXGxq5tbgD9Esvb6DgtKHJr
Hi/lPMVM0XmN/DIXhY9x7SqO2cKvEAU=
=XwLB
-----END PGP SIGNATURE-----
Merge tag 'for-linus-4.17-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen cleanup from Juergen Gross:
"One cleanup to remove VLAs from the kernel"
* tag 'for-linus-4.17-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
x86/xen: Remove use of VLAs
There's an ongoing effort to remove VLAs[1] from the kernel to eventually
turn on -Wvla. It turns out, the few VLAs in use in Xen produce only a
single entry array that is always bounded by GDT_SIZE. Clean up the code to
get rid of the VLA and the loop.
[1] https://lkml.org/lkml/2018/3/7/621
Signed-off-by: Laura Abbott <labbott@redhat.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
[boris: Use BUG_ON(size>PAGE_SIZE) instead of GDT_SIZE]
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Pull x86 fixes from Thomas Gleixner:
"A set of fixes and updates for x86:
- Address a swiotlb regression which was caused by the recent DMA
rework and made driver fail because dma_direct_supported() returned
false
- Fix a signedness bug in the APIC ID validation which caused invalid
APIC IDs to be detected as valid thereby bloating the CPU possible
space.
- Fix inconsisten config dependcy/select magic for the MFD_CS5535
driver.
- Fix a corruption of the physical address space bits when encryption
has reduced the address space and late cpuinfo updates overwrite
the reduced bit information with the original value.
- Dominiks syscall rework which consolidates the architecture
specific syscall functions so all syscalls can be wrapped with the
same macros. This allows to switch x86/64 to struct pt_regs based
syscalls. Extend the clearing of user space controlled registers in
the entry patch to the lower registers"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/apic: Fix signedness bug in APIC ID validity checks
x86/cpu: Prevent cpuinfo_x86::x86_phys_bits adjustment corruption
x86/olpc: Fix inconsistent MFD_CS5535 configuration
swiotlb: Use dma_direct_supported() for swiotlb_ops
syscalls/x86: Adapt syscall_wrapper.h to the new syscall stub naming convention
syscalls/core, syscalls/x86: Rename struct pt_regs-based sys_*() to __x64_sys_*()
syscalls/core, syscalls/x86: Clean up compat syscall stub naming convention
syscalls/core, syscalls/x86: Clean up syscall stub naming convention
syscalls/x86: Extend register clearing on syscall entry to lower registers
syscalls/x86: Unconditionally enable 'struct pt_regs' based syscalls on x86_64
syscalls/x86: Use 'struct pt_regs' based syscall calling for IA32_EMULATION and x32
syscalls/core: Prepare CONFIG_ARCH_HAS_SYSCALL_WRAPPER=y for compat syscalls
syscalls/x86: Use 'struct pt_regs' based syscall calling convention for 64-bit syscalls
syscalls/core: Introduce CONFIG_ARCH_HAS_SYSCALL_WRAPPER=y
x86/syscalls: Don't pointlessly reload the system call number
x86/mm: Fix documentation of module mapping range with 4-level paging
x86/cpuid: Switch to 'static const' specifier
-----BEGIN PGP SIGNATURE-----
iQEzBAABCAAdFiEEhRJncuj2BJSl0Jf3sN6d1ii/Ey8FAlrPnM8ACgkQsN6d1ii/
Ey9Kzwf/eQVb6zzn7FDHAb6pLaZ5i2xi2xohsKmhAVQIEa94rZ3mLoRegtnIfyjO
RcjjSAzHSZO9NQgNA2ALdu6bBdzu4/ywQEQCnY2Gqxp0ocG/+k3p/FqLHZGdcqPo
e3gpcVxHSFWUCCGm1t3umI25driqrUq4xa6UFi2IB4djDvTrK/JsSygKx6GiVujL
2eV7v7rgqaaVZQyo8iOd+LlWuKZewKLfnALUDC21X5J2HmvfoyTdn85kldzbiIsG
YR7mcfgAtAVTyCfgXI3eqAGpRFEyqR4ga87oahdV3/iW+4wreh4hm2Xd/IETXklv
Epxyet8IlMB9886PuZhZqgnW6o1RDA==
=z3bP
-----END PGP SIGNATURE-----
Merge tag 'for-linus-4.17-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fixes from Juergen Gross:
"A few fixes of Xen related core code and drivers"
* tag 'for-linus-4.17-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/pvh: Indicate XENFEAT_linux_rsdp_unrestricted to Xen
xen/acpi: off by one in read_acpi_id()
xen/acpi: upload _PSD info for non Dom0 CPUs too
x86/xen: Delay get_cpu_cap until stack canary is established
xen: xenbus_dev_frontend: Verify body of XS_TRANSACTION_END
xen: xenbus: Catch closing of non existent transactions
xen: xenbus_dev_frontend: Fix XS_TRANSACTION_END handling
- Rework the idle loop in order to prevent CPUs from spending too
much time in shallow idle states by making it stop the scheduler
tick before putting the CPU into an idle state only if the idle
duration predicted by the idle governor is long enough. That
required the code to be reordered to invoke the idle governor
before stopping the tick, among other things (Rafael Wysocki,
Frederic Weisbecker, Arnd Bergmann).
- Add the missing description of the residency sysfs attribute to
the cpuidle documentation (Prashanth Prakash).
- Finalize the cpufreq cleanup moving frequency table validation
from drivers to the core (Viresh Kumar).
- Fix a clock leak regression in the armada-37xx cpufreq driver
(Gregory Clement).
- Fix the initialization of the CPU performance data structures
for shared policies in the CPPC cpufreq driver (Shunyong Yang).
- Clean up the ti-cpufreq, intel_pstate and CPPC cpufreq drivers
a bit (Viresh Kumar, Rafael Wysocki).
- Mark the expected switch fall-throughs in the PM QoS core (Gustavo
Silva).
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2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=Pnk4
-----END PGP SIGNATURE-----
Merge tag 'pm-4.17-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull more power management updates from Rafael Wysocki:
"These include one big-ticket item which is the rework of the idle loop
in order to prevent CPUs from spending too much time in shallow idle
states. It reduces idle power on some systems by 10% or more and may
improve performance of workloads in which the idle loop overhead
matters. This has been in the works for several weeks and it has been
tested and reviewed quite thoroughly.
Also included are changes that finalize the cpufreq cleanup moving
frequency table validation from drivers to the core, a few fixes and
cleanups of cpufreq drivers, a cpuidle documentation update and a PM
QoS core update to mark the expected switch fall-throughs in it.
Specifics:
- Rework the idle loop in order to prevent CPUs from spending too
much time in shallow idle states by making it stop the scheduler
tick before putting the CPU into an idle state only if the idle
duration predicted by the idle governor is long enough.
That required the code to be reordered to invoke the idle governor
before stopping the tick, among other things (Rafael Wysocki,
Frederic Weisbecker, Arnd Bergmann).
- Add the missing description of the residency sysfs attribute to the
cpuidle documentation (Prashanth Prakash).
- Finalize the cpufreq cleanup moving frequency table validation from
drivers to the core (Viresh Kumar).
- Fix a clock leak regression in the armada-37xx cpufreq driver
(Gregory Clement).
- Fix the initialization of the CPU performance data structures for
shared policies in the CPPC cpufreq driver (Shunyong Yang).
- Clean up the ti-cpufreq, intel_pstate and CPPC cpufreq drivers a
bit (Viresh Kumar, Rafael Wysocki).
- Mark the expected switch fall-throughs in the PM QoS core (Gustavo
Silva)"
* tag 'pm-4.17-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (23 commits)
tick-sched: avoid a maybe-uninitialized warning
cpufreq: Drop cpufreq_table_validate_and_show()
cpufreq: SCMI: Don't validate the frequency table twice
cpufreq: CPPC: Initialize shared perf capabilities of CPUs
cpufreq: armada-37xx: Fix clock leak
cpufreq: CPPC: Don't set transition_latency
cpufreq: ti-cpufreq: Use builtin_platform_driver()
cpufreq: intel_pstate: Do not include debugfs.h
PM / QoS: mark expected switch fall-throughs
cpuidle: Add definition of residency to sysfs documentation
time: hrtimer: Use timerqueue_iterate_next() to get to the next timer
nohz: Avoid duplication of code related to got_idle_tick
nohz: Gather tick_sched booleans under a common flag field
cpuidle: menu: Avoid selecting shallow states with stopped tick
cpuidle: menu: Refine idle state selection for running tick
sched: idle: Select idle state before stopping the tick
time: hrtimer: Introduce hrtimer_next_event_without()
time: tick-sched: Split tick_nohz_stop_sched_tick()
cpuidle: Return nohz hint from cpuidle_select()
jiffies: Introduce USER_TICK_USEC and redefine TICK_USEC
...
Juergen Gross noticed that commit f7f99100d8 ("mm: stop zeroing memory
during allocation in vmemmap") broke XEN PV domains when deferred struct
page initialization is enabled.
This is because the xen's PagePinned() flag is getting erased from
struct pages when they are initialized later in boot.
Juergen fixed this problem by disabling deferred pages on xen pv
domains. It is desirable, however, to have this feature available as it
reduces boot time. This fix re-enables the feature for pv-dmains, and
fixes the problem the following way:
The fix is to delay setting PagePinned flag until struct pages for all
allocated memory are initialized, i.e. until after free_all_bootmem().
A new x86_init.hyper op init_after_bootmem() is called to let xen know
that boot allocator is done, and hence struct pages for all the
allocated memory are now initialized. If deferred page initialization
is enabled, the rest of struct pages are going to be initialized later
in boot once page_alloc_init_late() is called.
xen_after_bootmem() walks page table's pages and marks them pinned.
Link: http://lkml.kernel.org/r/20180226160112.24724-2-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Juergen Gross <jgross@suse.com>
Tested-by: Juergen Gross <jgross@suse.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Mathias Krause <minipli@googlemail.com>
Cc: Jinbum Park <jinb.park7@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Jia Zhang <zhang.jia@linux.alibaba.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The APIC ID as parsed from ACPI MADT is validity checked with the
apic->apic_id_valid() callback, which depends on the selected APIC type.
For non X2APIC types APIC IDs >= 0xFF are invalid, but values > 0x7FFFFFFF
are detected as valid. This happens because the 'apicid' argument of the
apic_id_valid() callback is type 'int'. So the resulting comparison
apicid < 0xFF
evaluates to true for all unsigned int values > 0x7FFFFFFF which are handed
to default_apic_id_valid(). As a consequence, invalid APIC IDs in !X2APIC
mode are considered valid and accounted as possible CPUs.
Change the apicid argument type of the apic_id_valid() callback to u32 so
the evaluation is unsigned and returns the correct result.
[ tglx: Massaged changelog ]
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Cc: jgross@suse.com
Cc: Dou Liyang <douly.fnst@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/1523322966-10296-1-git-send-email-lirongqing@baidu.com
Juergen Gross