Latest virtio spec says the feature bit name is VIRTIO_BLK_F_FLUSH,
VIRTIO_BLK_F_WCE is the legacy name. virtio blk header says exactly the
reverse - fix that and update driver code to match.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
This switches to vring_create_virtqueue, simplifying the driver and
adding DMA API support.
This fixes virtio-pci on platforms and busses that have IOMMUs. This
will break the experimental QEMU Q35 IOMMU support until QEMU is
fixed. In exchange, it fixes physical virtio hardware as well as
virtio-pci running under Xen.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This switches to vring_create_virtqueue, simplifying the driver and
adding DMA API support.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This leaves vring_new_virtqueue alone for compatbility, but it
adds two new improved APIs:
vring_create_virtqueue: Creates a virtqueue backed by automatically
allocated coherent memory. (Some day it this could be extended to
support non-coherent memory, too, if there ends up being a platform
on which it's worthwhile.)
__vring_new_virtqueue: Creates a virtqueue with a manually-specified
layout. This should allow mic_virtio to work much more cleanly.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
virtio_ring currently sends the device (usually a hypervisor)
physical addresses of its I/O buffers. This is okay when DMA
addresses and physical addresses are the same thing, but this isn't
always the case. For example, this never works on Xen guests, and
it is likely to fail if a physical "virtio" device ever ends up
behind an IOMMU or swiotlb.
The immediate use case for me is to enable virtio on Xen guests.
For that to work, we need vring to support DMA address translation
as well as a corresponding change to virtio_pci or to another
driver.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This is a kludge, but no one has come up with a a better idea yet.
We'll introduce DMA API support guarded by vring_use_dma_api().
Eventually we may be able to return true on more and more systems,
and hopefully we can get rid of vring_use_dma_api() entirely some
day.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
As virtio-ccw will have dma ops, we can no longer default to the
zPCI ones. Make use of dev_archdata to keep the dma_ops per device.
The pci devices now use that to override the default, and the
default is changed to use the noop ops for everything that does not
specify a device specific one.
To compile without PCI support we will enable HAS_DMA all the time,
via the default config in lib/Kconfig.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Some of the alpha pci noop dma ops are identical to the common ones.
Use them.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
We are going to require dma_ops for several common drivers, even for
systems that do have an identity mapping. Lets provide some minimal
no-op dma_ops that can be used for that purpose.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
We don't want side effects. If something fails, we rollback vq->is_le to
its previous value.
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Looks like a copy-paste bug. The value is used as an optimization and a
wrong value probably isn't causing any serious damage. Found when
porting this code to Windows.
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cpu_dai id always equals 0, can't distinguish the
different SSC. Use platform_device id to record
and distinguish the different SSC.
Signed-off-by: Songjun Wu <songjun.wu@atmel.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add regulator ops callback for configuration of active-discharge
and provide necessarily information via regulator descriptor.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add support to enable/disable active discharge of regulator via
machine constraints. This configuration is done when setting
machine constraint during regulator register and if regulator
driver implemented the callback ops.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add helper function to set the state of active-discharge of
regulator using regmap. The HW regulator driver can directly
use this by providing the necessary information in the regulator
descriptor.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add support to enable/disable active discharge of regulator via
machine constraints. This configuration is done when setting
machine constraint during regulator register and if regulator
driver implemented the callback ops.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add common DT property for regulator node to support of
active discharge enable/disable configuration of regulator.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Whilst the default SLUB allocator happily just merges the original
allocation flags from kmem_cache_create() with those passed through
kmem_cache_alloc(), there is a code path in the SLAB allocator which
will aggressively BUG_ON() if the cache was created with SLAB_CACHE_DMA
but GFP_DMA is not specified for an allocation:
kernel BUG at mm/slab.c:2536!
Internal error: Oops - BUG: 0 [#1] SMP ARM
Modules linked in:[ 1.299311] Modules linked in:
CPU: 1 PID: 1 Comm: swapper/0 Not tainted
4.5.0-rc6-koelsch-05892-ge7e45ad53ab6795e #2270
Hardware name: Generic R8A7791 (Flattened Device Tree)
task: ef422040 ti: ef442000 task.ti: ef442000
PC is at cache_alloc_refill+0x2a0/0x530
LR is at _raw_spin_unlock+0x8/0xc
...
[<c02c6928>] (cache_alloc_refill) from [<c02c6630>] (kmem_cache_alloc+0x7c/0xd4)
[<c02c6630>] (kmem_cache_alloc) from [<c04444bc>]
(__arm_v7s_alloc_table+0x5c/0x278)
[<c04444bc>] (__arm_v7s_alloc_table) from [<c0444e1c>]
(__arm_v7s_map.constprop.6+0x68/0x25c)
[<c0444e1c>] (__arm_v7s_map.constprop.6) from [<c0445044>]
(arm_v7s_map+0x34/0xa4)
[<c0445044>] (arm_v7s_map) from [<c0c18ee4>] (arm_v7s_do_selftests+0x140/0x418)
[<c0c18ee4>] (arm_v7s_do_selftests) from [<c0201760>]
(do_one_initcall+0x100/0x1b4)
[<c0201760>] (do_one_initcall) from [<c0c00d4c>]
(kernel_init_freeable+0x120/0x1e8)
[<c0c00d4c>] (kernel_init_freeable) from [<c067a364>] (kernel_init+0x8/0xec)
[<c067a364>] (kernel_init) from [<c0206b68>] (ret_from_fork+0x14/0x2c)
Code: 1a000003 e7f001f2 e3130001 0a000000 (e7f001f2)
---[ end trace 190f6f6b84352efd ]---
Keep the peace by adding GFP_DMA when allocating a table.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
commit e5756c10d8
Author: Imre Deak <imre.deak@intel.com>
Date: Fri Aug 14 18:43:30 2015 +0300
drm/i915/bxt: don't allow cached GEM mappings on A stepping
Added an exception of disallowing snooping for Broxton A
stepping hardware but userptr was still enabling it regardless.
Move the check to HAS_SNOOP now that it is used from multiple
call sites and use it.
v2: Userptr cannot be supported when it cannot be coherent and
generalize the code better. (Chris Wilson)
v3: Make has_snoop true only when !has_llc. (Chris Wilson)
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Imre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1456920631-34302-1-git-send-email-tvrtko.ursulin@linux.intel.com
Since I maintain this driver as part of mac80211, add it to
the file list for mac80211; this helps submitters send it to
me instead of Kalle and also makes the build robot apply the
patches for it on the right tree for build attempts.
Acked-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Fix these compiler warnings:
media-git/include/media/media-device.h: In function 'media_device_pci_init':
media-git/include/media/media-device.h:610:9: warning: 'return' with a value, in function returning void
return NULL;
^
media-git/include/media/media-device.h: In function '__media_device_usb_init':
media-git/include/media/media-device.h:618:9: warning: 'return' with a value, in function returning void
return NULL;
^
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
git commit 26f15caaf9 ("s390/cmpxchg: simplify cmpxchg_double")
removed support for cmpxchg_double for two consecutive four byte
values, for which it would generate a cds instruction.
However I forgot to remove the corresponding define in our percpu
header file, which means that this_cpu_cmpxchg_double would now
incorrectly generate a cdsg instruction if being used on a double four
byte location. Therefore remove the percpu define as well.
There is currently no user and therefore no bug fixed with
this. Obviously any such user could and should simply use cmpxchg.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
commit e22cf8ca6f ("s390/cpumf: rework program parameter setting
to detect guest samples") requires guest changes to get proper
guest/host. We can do better: We can use the primary asn value,
which is set on all Linux variants to compare this with the host
pp value.
We now have the following cases:
1. Guest using PP
host sample: gpp == 0, asn == hpp --> host
guest sample: gpp != 0 --> guest
2. Guest not using PP
host sample: gpp == 0, asn == hpp --> host
guest sample: gpp == 0, asn != hpp --> guest
As soon as the host no longer sets CR4, we must back out
this heuristics - let's add a comment in switch_to.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
We have two close to identical report_user_fault functions.
Add a parameter to one and get rid of the other one in order
to reduce code duplication.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The double escape character sequence introduced with commit
272fa59ccb ("s390/dis: Fix handling of format specifiers") is not
necessary anymore since commit 561e103002 ("s390/dis: Fix printing
of the register numbers").
Instead this now generates an extra '%' character:
lg %%r1,160(%%r11)
So fix this and basically revert 272fa59ccb.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Git commit ab3f285f22
"KVM: s390/mm: try a cow on read only pages for key ops"
added a fixup_user_fault to set_guest_storage_key force a copy on
write if the page is mapped read-only. This is supposed to fix the
problem of differing storage keys for shared mappings, e.g. the
empty_zero_page.
But if the storage key is set before the pte is mapped the storage
key update is done on the pgste. A later fault will happily map the
shared page with the key from the pgste.
Eventually git commit 2faee8ff9d
"s390/mm: prevent and break zero page mappings in case of storage keys"
fixed this problem for the empty_zero_page. The commit makes sure that
guests enabled for storage keys will not use the empty_zero_page at all.
As the call to fixup_user_fault in set_guest_storage_key depends on the
order of the storage key operation vs. the fault that maps the pte
it does not really fix anything. Just remove it.
Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
git commit 1ec2772e0c ("s390/diag: add a statistic for diagnose
calls") added function calls to gather diagnose statistics.
In case of the dasd diag driver the function call was added between a
register asm statement which initialized register r2 and the inline
assembly itself. The function call clobbers the contents of register
r2 and therefore the diag 0x250 call behaves in a more or less random
way.
Fix this by extracting the function call into a separate function like
we do everywhere else.
Fixes: 1ec2772e0c ("s390/diag: add a statistic for diagnose calls")
Cc: <stable@vger.kernel.org> # 4.4+
Reported-and-tested-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
commit 0973128002
Author: Imre Deak <imre.deak@intel.com>
Date: Wed Feb 17 14:17:42 2016 +0200
drm/i915: Add helper to get a display power ref if it was already enabled
left the rpm wakelock assertions unbalanced if CONFIG_PM was disabled as
intel_runtime_pm_get_if_in_use() would return true without incrementing
the local bookkeeping required for the assertions.
Fixes: 0973128002 ("drm/i915: Add helper to get a display power ref if it was already enabled")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
CC: Mika Kuoppala <mika.kuoppala@intel.com>
CC: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
CC: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1456434628-22574-1-git-send-email-chris@chris-wilson.co.uk
Reviewed-by: Imre Deak <imre.deak@intel.com>
(cherry picked from commit 135dc79efb)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
During system suspend we need to first disable power wells then
unitialize the display core. In case power well support is disabled we
did this in the wrong order, so fix this up.
Fixes: d314cd43 ("drm/i915: fix handling of the disable_power_well module option")
CC: stable@vger.kernel.org
CC: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1456778945-5411-1-git-send-email-imre.deak@intel.com
(cherry picked from commit 2622d79bd9)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
This patch adds the ability to be able to save the VSX registers to the
thread struct without giving up (disabling the facility) next time the
process returns to userspace.
This patch builds on a previous optimisation for the FPU and VEC registers
in the thread copy path to avoid a possibly pointless reload of VSX state.
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch adds the ability to be able to save the VEC registers to the
thread struct without giving up (disabling the facility) next time the
process returns to userspace.
This patch builds on a previous optimisation for the FPU registers in the
thread copy path to avoid a possibly pointless reload of VEC state.
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch adds the ability to be able to save the FPU registers to the
thread struct without giving up (disabling the facility) next time the
process returns to userspace.
This patch optimises the thread copy path (as a result of a fork() or
clone()) so that the parent thread can return to userspace with hot
registers avoiding a possibly pointless reload of FPU register state.
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This prepares for the decoupling of saving {fpu,altivec,vsx} registers and
marking {fpu,altivec,vsx} as being unused by a thread.
Currently giveup_{fpu,altivec,vsx}() does both however optimisations to
task switching can be made if these two operations are decoupled.
save_all() will permit the saving of registers to thread structs and leave
threads MSR with bits enabled.
This patch introduces no functional change.
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Currently the FPU, VEC and VSX facilities are lazily loaded. This is not
a problem unless a process is using these facilities.
Modern versions of GCC are very good at automatically vectorising code,
new and modernised workloads make use of floating point and vector
facilities, even the kernel makes use of vectorised memcpy.
All this combined greatly increases the cost of a syscall since the
kernel uses the facilities sometimes even in syscall fast-path making it
increasingly common for a thread to take an *_unavailable exception soon
after a syscall, not to mention potentially taking all three.
The obvious overcompensation to this problem is to simply always load
all the facilities on every exit to userspace. Loading up all FPU, VEC
and VSX registers every time can be expensive and if a workload does
avoid using them, it should not be forced to incur this penalty.
An 8bit counter is used to detect if the registers have been used in the
past and the registers are always loaded until the value wraps to back
to zero.
Several versions of the assembly in entry_64.S were tested:
1. Always calling C.
2. Performing a common case check and then calling C.
3. A complex check in asm.
After some benchmarking it was determined that avoiding C in the common
case is a performance benefit (option 2). The full check in asm (option
3) greatly complicated that codepath for a negligible performance gain
and the trade-off was deemed not worth it.
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
[mpe: Move load_vec in the struct to fill an existing hole, reword change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
fixup
Currently when threads get scheduled off they always giveup the FPU,
Altivec (VMX) and Vector (VSX) units if they were using them. When they are
scheduled back on a fault is then taken to enable each facility and load
registers. As a result explicitly disabling FPU/VMX/VSX has not been
necessary.
Future changes and optimisations remove this mandatory giveup and fault
which could cause calls such as clone() and fork() to copy threads and run
them later with FPU/VMX/VSX enabled but no registers loaded.
This patch starts the process of having MSR_{FP,VEC,VSX} mean that a
threads registers are hot while not having MSR_{FP,VEC,VSX} means that the
registers must be loaded. This allows for a smarter return to userspace.
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Load up the non volatile FPU and VMX regs and ensure that they are the
expected value in a signal handler
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Loop in assembly checking the registers with many threads.
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Test that the non volatile floating point and Altivec registers get
correctly preserved across the fork() syscall.
fork() works nicely for this purpose, the registers should be the same for
both parent and child
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
[mpe: Add include guards to basic_asm.h, minor formatting]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
LTO can cause GCC to inline some functions which have attributes set.
The act of inlining the functions can lead to GCC forgetting about the
attributes which leads to incorrect tests.
Notable example being: __attribute__((__target__("no-vsx")))
LTO can also interact strangely with custom assembly functions and cause
tests to intermittently fail.
Both these cases are hard to detect and require manual inspection of
binaries which is unlikely to happen for all tests. Furthermore, LTO
optimisations are not necessary for selftests and correctness is
paramount and as such it is best to disable LTO.
LTO can be enabled on a per test basis.
A pseries_le_defconfig kernel on a POWER8 was used to determine that the
same subset of selftests pass and fail with and without -flto in the
common Makefile.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Gcc helpfully points out that we're accessing past the end of the gprs
array:
tm-signal-msr-resv.c: In function 'signal_usr1':
tm-signal-msr-resv.c:43:37: error: array subscript is above array bounds [-Werror=array-bounds]
ucp->uc_mcontext.regs->gpr[PT_MSR] |= (7ULL);
We haven't noticed previously because -flto was hiding it somehow.
The code is confused, PT_MSR isn't a gpr, instead it's in
uc_regs->gregs, so fix it.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This change will also make Coverity happy by avoiding a theoretical NULL
pointer dereference; yet another reason is to use the above helper function
to tighten the code and make it more readable.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
This change will also make Coverity happy by avoiding a theoretical NULL
pointer dereference; yet another reason is to use the above helper function
to tighten the code and make it more readable.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add support for third Intel Broxton variant and update comment for
A-Step variant.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Steve Sakoman <steve.sakoman@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Commit 8439e62a15 ("arm64: mm: use bit ops rather than arithmetic in
pa/va translations") changed the boundary check against PAGE_OFFSET from
an arithmetic comparison to a bit test. This means we now silently assume
that PAGE_OFFSET is a power of 2 that divides the kernel virtual address
space into two equal halves. So make that assumption explicit.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
vmx.c writes the TSC_MULTIPLIER field in vmx_vcpu_load, but only when a
vcpu has migrated physical cpus. Record the last value written and
update in vmx_vcpu_load on any change, otherwise a cpu migration must
occur for TSC frequency scaling to take effect.
Cc: stable@vger.kernel.org
Fixes: ff2c3a1803
Signed-off-by: Owen Hofmann <osh@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Returning directly whatever copy_to_user(...) or copy_from_user(...)
returns may not do the right thing if there's a pagefault:
copy_to_user/copy_from_user return the number of bytes not copied in
this case, but ioctls need to return -EFAULT instead.
Fix up kvm on mips to do
return copy_to_user(...)) ? -EFAULT : 0;
and
return copy_from_user(...)) ? -EFAULT : 0;
everywhere.
Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>