A reference to the framebuffer device struct fb_info is stored in the file
private data, but this reference could no longer be valid and must not be
accessed directly. Instead, the file_fb_info() accessor function must be
used since it does sanity checking to make sure that the fb_info is valid.
This can happen for example if the registered framebuffer device is for a
driver that just uses a framebuffer provided by the system firmware. In
that case, the fbdev core would unregister the framebuffer device when a
real video driver is probed and ask to remove conflicting framebuffers.
The bug has been present for a long time but commit 27599aacba ("fbdev:
Hot-unplug firmware fb devices on forced removal") unmasked it since the
fbdev core started unregistering the framebuffers' devices associated.
Fixes: 27599aacba ("fbdev: Hot-unplug firmware fb devices on forced removal")
Reported-by: Maxime Ripard <maxime@cerno.tech>
Reported-by: Junxiao Chang <junxiao.chang@intel.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220502135014.377945-1-javierm@redhat.com
commit b4bdc4fbf8 ("soc: sunxi: Deal with the MBUS DMA offsets in a
central place") added a platform device notifier that sets the DMA
offset for all of the display engine frontend and backend devices.
The code applying the offset to DMA buffer physical addresses was then
removed from the backend driver in commit 756668ba68 ("drm/sun4i:
backend: Remove the MBUS quirks"), but the code subtracting PHYS_OFFSET
was left in the frontend driver.
As a result, the offset was applied twice in the frontend driver. This
likely went unnoticed because it only affects specific configurations
(scaling or certain pixel formats) where the frontend is used, on boards
with both one of these older SoCs and more than 1 GB of DRAM.
In addition, the references to PHYS_OFFSET prevent compiling the driver
on architectures where PHYS_OFFSET is not defined.
Fixes: b4bdc4fbf8 ("soc: sunxi: Deal with the MBUS DMA offsets in a central place")
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20220424162633.12369-4-samuel@sholland.org
Commit '80253168dbfd ("drm: of: Lookup if child node has panel or
bridge")' attempted to simplify the case of expressing a simple panel
under a DSI controller, by assuming that the first non-graph child node
was a panel or bridge.
Unfortunately for non-trivial cases the first child node might not be a
panel or bridge. Examples of this can be a aux-bus in the case of
DisplayPort, or an opp-table represented before the panel node.
In these cases the reverted commit prevents the caller from ever finding
a reference to the panel.
This reverts commit '80253168dbfd ("drm: of: Lookup if child node has
panel or bridge")', in favor of using an explicit graph reference to the
panel in the trivial case as well.
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20220420231230.58499-2-bjorn.andersson@linaro.org
Commit '80253168dbfd ("drm: of: Lookup if child node has panel or
bridge")' introduced the ability to describe a panel under a display
controller without having to use a graph to connect the controller to
its single child panel (or bridge).
The implementation of this would find the first non-graph node and
attempt to acquire the related panel or bridge. This prevents cases
where any other child node, such as a aux bus for a DisplayPort
controller, or an opp-table to find the referenced panel.
Commit '67bae5f28c89 ("drm: of: Properly try all possible cases for
bridge/panel detection")' attempted to solve this problem by not
bypassing the graph reference lookup before attempting to find the panel
or bridge.
While this does solve the case where a proper graph reference is
present, it does not allow the caller to distinguish between a
yet-to-be-probed panel or bridge and the absence of a reference to a
panel.
One such case is a DisplayPort controller that on some boards have an
explicitly described reference to a panel, but on others have a
discoverable DisplayPort display attached (which doesn't need to be
expressed in DeviceTree).
This reverts commit '67bae5f28c89 ("drm: of: Properly try all possible
cases for bridge/panel detection")', as a step towards reverting commit
'80253168dbfd ("drm: of: Lookup if child node has panel or bridge")'.
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20220420231230.58499-1-bjorn.andersson@linaro.org
v2: Add the last part of the ref count fix which was spotted by
Philipp Sieweck where the ref count of cpu writers is off due to
ERESTARTSYS or EBUSY during bo waits.
The initial GEM port broke refcounting on shareable (prime) surfaces and
memory evictions. The prime surfaces broke because the parent surfaces
weren't increasing the ref count on GEM surfaces, which meant that
the memory backing textures could have been deleted while the texture
was still accessible. The evictions broke due to a typo, the code was
supposed to exit if the passed buffers were not vmw_buffer_object
not if they were. They're tied because the evictions depend on having
memory to actually evict.
This fixes crashes with XA state tracker which is used for xrender
acceleration on xf86-video-vmware, apps/tests which use a lot of
memory (a good test being the piglit's streaming-texture-leak) and
desktops.
Signed-off-by: Zack Rusin <zackr@vmware.com>
Fixes: 8afa13a058 ("drm/vmwgfx: Implement DRIVER_GEM")
Reported-by: Philipp Sieweck <psi@informatik.uni-kiel.de>
Cc: <stable@vger.kernel.org> # v5.17+
Reviewed-by: Maaz Mombasawala <mombasawalam@vmware.com>
Reviewed-by: Martin Krastev <krastevm@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220420040328.1007409-1-zack@kde.org
If CONFIG_DRM_VC4=y, CONFIG_RASPBERRYPI_FIRMWARE=m, CONFIG_COMPILE_TEST=n,
bulding fails:
drivers/gpu/drm/vc4/vc4_drv.o: In function `vc4_drm_bind':
vc4_drv.c:(.text+0x320): undefined reference to `rpi_firmware_get'
vc4_drv.c:(.text+0x320): relocation truncated to fit: R_AARCH64_CALL26 against undefined symbol `rpi_firmware_get'
vc4_drv.c:(.text+0x34c): undefined reference to `rpi_firmware_property'
vc4_drv.c:(.text+0x34c): relocation truncated to fit: R_AARCH64_CALL26 against undefined symbol `rpi_firmware_property'
vc4_drv.c:(.text+0x354): undefined reference to `rpi_firmware_put'
vc4_drv.c:(.text+0x354): relocation truncated to fit: R_AARCH64_CALL26 against undefined symbol `rpi_firmware_put'
Make DRM_VC4 depends on RASPBERRYPI_FIRMWARE || (COMPILE_TEST && !RASPBERRYPI_FIRMWARE) to fix this.
Fixes: c406ad5e4a ("drm/vc4: Notify the firmware when DRM is in charge")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zheng Bin <zhengbin13@huawei.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20220411024325.3968413-1-zhengbin13@huawei.com
OF framebuffers do not have an underlying device in the Linux
device hierarchy. Do a regular unregister call instead of hot
unplugging such a non-existing device. Fixes a NULL dereference.
An example error message on ppc64le is shown below.
BUG: Kernel NULL pointer dereference on read at 0x00000060
Faulting instruction address: 0xc00000000080dfa4
Oops: Kernel access of bad area, sig: 11 [#1]
LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
[...]
CPU: 2 PID: 139 Comm: systemd-udevd Not tainted 5.17.0-ae085d7f9365 #1
NIP: c00000000080dfa4 LR: c00000000080df9c CTR: c000000000797430
REGS: c000000004132fe0 TRAP: 0300 Not tainted (5.17.0-ae085d7f9365)
MSR: 8000000002009033 <SF,VEC,EE,ME,IR,DR,RI,LE> CR: 28228282 XER: 20000000
CFAR: c00000000000c80c DAR: 0000000000000060 DSISR: 40000000 IRQMASK: 0
GPR00: c00000000080df9c c000000004133280 c00000000169d200 0000000000000029
GPR04: 00000000ffffefff c000000004132f90 c000000004132f88 0000000000000000
GPR08: c0000000015658f8 c0000000015cd200 c0000000014f57d0 0000000048228283
GPR12: 0000000000000000 c00000003fffe300 0000000020000000 0000000000000000
GPR16: 0000000000000000 0000000113fc4a40 0000000000000005 0000000113fcfb80
GPR20: 000001000f7283b0 0000000000000000 c000000000e4a588 c000000000e4a5b0
GPR24: 0000000000000001 00000000000a0000 c008000000db0168 c0000000021f6ec0
GPR28: c0000000016d65a8 c000000004b36460 0000000000000000 c0000000016d64b0
NIP [c00000000080dfa4] do_remove_conflicting_framebuffers+0x184/0x1d0
[c000000004133280] [c00000000080df9c] do_remove_conflicting_framebuffers+0x17c/0x1d0 (unreliable)
[c000000004133350] [c00000000080e4d0] remove_conflicting_framebuffers+0x60/0x150
[c0000000041333a0] [c00000000080e6f4] remove_conflicting_pci_framebuffers+0x134/0x1b0
[c000000004133450] [c008000000e70438] drm_aperture_remove_conflicting_pci_framebuffers+0x90/0x100 [drm]
[c000000004133490] [c008000000da0ce4] bochs_pci_probe+0x6c/0xa64 [bochs]
[...]
[c000000004133db0] [c00000000002aaa0] system_call_exception+0x170/0x2d0
[c000000004133e10] [c00000000000c3cc] system_call_common+0xec/0x250
The bug [1] was introduced by commit 27599aacba ("fbdev: Hot-unplug
firmware fb devices on forced removal"). Most firmware framebuffers
have an underlying platform device, which can be hot-unplugged
before loading the native graphics driver. OF framebuffers do not
(yet) have that device. Fix the code by unregistering the framebuffer
as before without a hot unplug.
Tested with 5.17 on qemu ppc64le emulation.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 27599aacba ("fbdev: Hot-unplug firmware fb devices on forced removal")
Reported-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Cc: Zack Rusin <zackr@vmware.com>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: stable@vger.kernel.org # v5.11+
Cc: Helge Deller <deller@gmx.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Zheyu Ma <zheyuma97@gmail.com>
Cc: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Cc: Zhen Lei <thunder.leizhen@huawei.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Link: https://lore.kernel.org/all/YkHXO6LGHAN0p1pq@debian/ # [1]
Link: https://patchwork.freedesktop.org/patch/msgid/20220404194402.29974-1-tzimmermann@suse.de
MIPI-DSI devices, if they are controlled through the bus itself, have to
be described as a child node of the controller they are attached to.
Thus, there's no requirement on the controller having an OF-Graph output
port to model the data stream: it's assumed that it would go from the
parent to the child.
However, some bridges controlled through the DSI bus still require an
input OF-Graph port, thus requiring a controller with an OF-Graph output
port. This prevents those bridges from being used with the controllers
that do not have one without any particular reason to.
Let's drop that requirement.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220323154823.839469-1-maxime@cerno.tech
Pull more tracing updates from Steven Rostedt:
- Rename the staging files to give them some meaning. Just
stage1,stag2,etc, does not show what they are for
- Check for NULL from allocation in bootconfig
- Hold event mutex for dyn_event call in user events
- Mark user events to broken (to work on the API)
- Remove eBPF updates from user events
- Remove user events from uapi header to keep it from being installed.
- Move ftrace_graph_is_dead() into inline as it is called from hot
paths and also convert it into a static branch.
* tag 'trace-v5.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Move user_events.h temporarily out of include/uapi
ftrace: Make ftrace_graph_is_dead() a static branch
tracing: Set user_events to BROKEN
tracing/user_events: Remove eBPF interfaces
tracing/user_events: Hold event_mutex during dyn_event_add
proc: bootconfig: Add null pointer check
tracing: Rename the staging files for trace_events
Pull clk fix from Stephen Boyd:
"A single revert to fix a boot regression seen when clk_put() started
dropping rate range requests. It's best to keep various systems
booting so we'll kick this out and try again next time"
* tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
Revert "clk: Drop the rate range on clk_put()"
Pull x86 fixes from Thomas Gleixner:
"A set of x86 fixes and updates:
- Make the prctl() for enabling dynamic XSTATE components correct so
it adds the newly requested feature to the permission bitmap
instead of overwriting it. Add a selftest which validates that.
- Unroll string MMIO for encrypted SEV guests as the hypervisor
cannot emulate it.
- Handle supervisor states correctly in the FPU/XSTATE code so it
takes the feature set of the fpstate buffer into account. The
feature sets can differ between host and guest buffers. Guest
buffers do not contain supervisor states. So far this was not an
issue, but with enabling PASID it needs to be handled in the buffer
offset calculation and in the permission bitmaps.
- Avoid a gazillion of repeated CPUID invocations in by caching the
values early in the FPU/XSTATE code.
- Enable CONFIG_WERROR in x86 defconfig.
- Make the X86 defconfigs more useful by adapting them to Y2022
reality"
* tag 'x86-urgent-2022-04-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/fpu/xstate: Consolidate size calculations
x86/fpu/xstate: Handle supervisor states in XSTATE permissions
x86/fpu/xsave: Handle compacted offsets correctly with supervisor states
x86/fpu: Cache xfeature flags from CPUID
x86/fpu/xsave: Initialize offset/size cache early
x86/fpu: Remove unused supervisor only offsets
x86/fpu: Remove redundant XCOMP_BV initialization
x86/sev: Unroll string mmio with CC_ATTR_GUEST_UNROLL_STRING_IO
x86/config: Make the x86 defconfigs a bit more usable
x86/defconfig: Enable WERROR
selftests/x86/amx: Update the ARCH_REQ_XCOMP_PERM test
x86/fpu/xstate: Fix the ARCH_REQ_XCOMP_PERM implementation
Pull RT signal fix from Thomas Gleixner:
"Revert the RT related signal changes. They need to be reworked and
generalized"
* tag 'core-urgent-2022-04-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Revert "signal, x86: Delay calling signals in atomic on RT enabled kernels"
Pull more dma-mapping updates from Christoph Hellwig:
- fix a regression in dma remap handling vs AMD memory encryption (me)
- finally kill off the legacy PCI DMA API (Christophe JAILLET)
* tag 'dma-mapping-5.18-1' of git://git.infradead.org/users/hch/dma-mapping:
dma-mapping: move pgprot_decrypted out of dma_pgprot
PCI/doc: cleanup references to the legacy PCI DMA API
PCI: Remove the deprecated "pci-dma-compat.h" API
Pull more perf tools updates from Arnaldo Carvalho de Melo:
- Avoid SEGV if core.cpus isn't set in 'perf stat'.
- Stop depending on .git files for building PERF-VERSION-FILE, used in
'perf --version', fixing some perf tools build scenarios.
- Convert tracepoint.py example to python3.
- Update UAPI header copies from the kernel sources: socket,
mman-common, msr-index, KVM, i915 and cpufeatures.
- Update copy of libbpf's hashmap.c.
- Directly return instead of using local ret variable in
evlist__create_syswide_maps(), found by coccinelle.
* tag 'perf-tools-for-v5.18-2022-04-02' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
perf python: Convert tracepoint.py example to python3
perf evlist: Directly return instead of using local ret variable
perf cpumap: More cpu map reuse by merge.
perf cpumap: Add is_subset function
perf evlist: Rename cpus to user_requested_cpus
perf tools: Stop depending on .git files for building PERF-VERSION-FILE
tools headers cpufeatures: Sync with the kernel sources
tools headers UAPI: Sync drm/i915_drm.h with the kernel sources
tools headers UAPI: Sync linux/kvm.h with the kernel sources
tools kvm headers arm64: Update KVM headers from the kernel sources
tools arch x86: Sync the msr-index.h copy with the kernel sources
tools headers UAPI: Sync asm-generic/mman-common.h with the kernel
perf beauty: Update copy of linux/socket.h with the kernel sources
perf tools: Update copy of libbpf's hashmap.c
perf stat: Avoid SEGV if core.cpus isn't set
Pull Kbuild fixes from Masahiro Yamada:
- Fix empty $(PYTHON) expansion.
- Fix UML, which got broken by the attempt to suppress Clang warnings.
- Fix warning message in modpost.
* tag 'kbuild-fixes-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
modpost: restore the warning message for missing symbol versions
Revert "um: clang: Strip out -mno-global-merge from USER_CFLAGS"
kbuild: Remove '-mno-global-merge'
kbuild: fix empty ${PYTHON} in scripts/link-vmlinux.sh
kconfig: remove stale comment about removed kconfig_print_symbol()
Pull MIPS fixes from Thomas Bogendoerfer:
- build fix for gpio
- fix crc32 build problems
- check for failed memory allocations
* tag 'mips_5.18_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
MIPS: crypto: Fix CRC32 code
MIPS: rb532: move GPIOD definition into C-files
MIPS: lantiq: check the return value of kzalloc()
mips: sgi-ip22: add a check for the return of kzalloc()
Pull kvm fixes from Paolo Bonzini:
- Only do MSR filtering for MSRs accessed by rdmsr/wrmsr
- Documentation improvements
- Prevent module exit until all VMs are freed
- PMU Virtualization fixes
- Fix for kvm_irq_delivery_to_apic_fast() NULL-pointer dereferences
- Other miscellaneous bugfixes
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (42 commits)
KVM: x86: fix sending PV IPI
KVM: x86/mmu: do compare-and-exchange of gPTE via the user address
KVM: x86: Remove redundant vm_entry_controls_clearbit() call
KVM: x86: cleanup enter_rmode()
KVM: x86: SVM: fix tsc scaling when the host doesn't support it
kvm: x86: SVM: remove unused defines
KVM: x86: SVM: move tsc ratio definitions to svm.h
KVM: x86: SVM: fix avic spec based definitions again
KVM: MIPS: remove reference to trap&emulate virtualization
KVM: x86: document limitations of MSR filtering
KVM: x86: Only do MSR filtering when access MSR by rdmsr/wrmsr
KVM: x86/emulator: Emulate RDPID only if it is enabled in guest
KVM: x86/pmu: Fix and isolate TSX-specific performance event logic
KVM: x86: mmu: trace kvm_mmu_set_spte after the new SPTE was set
KVM: x86/svm: Clear reserved bits written to PerfEvtSeln MSRs
KVM: x86: Trace all APICv inhibit changes and capture overall status
KVM: x86: Add wrappers for setting/clearing APICv inhibits
KVM: x86: Make APICv inhibit reasons an enum and cleanup naming
KVM: X86: Handle implicit supervisor access with SMAP
KVM: X86: Rename variable smap to not_smap in permission_fault()
...
Pull block driver fix from Jens Axboe:
"Got two reports on nbd spewing warnings on load now, which is a
regression from a commit that went into your tree yesterday.
Revert the problematic change for now"
* tag 'for-5.18/drivers-2022-04-02' of git://git.kernel.dk/linux-block:
Revert "nbd: fix possible overflow on 'first_minor' in nbd_dev_add()"
Pull pci fix from Bjorn Helgaas:
- Fix Hyper-V "defined but not used" build issue added during merge
window (YueHaibing)
* tag 'pci-v5.18-changes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
PCI: hv: Remove unused hv_set_msi_entry_from_desc()
Pull chrome platform updates from Benson Leung:
"cros_ec_typec:
- Check for EC device - Fix a crash when using the cros_ec_typec
driver on older hardware not capable of typec commands
- Make try power role optional
- Mux configuration reorganization series from Prashant
cros_ec_debugfs:
- Fix use after free. Thanks Tzung-bi
sensorhub:
- cros_ec_sensorhub fixup - Split trace include file
misc:
- Add new mailing list for chrome-platform development:
chrome-platform@lists.linux.dev
Now with patchwork!"
* tag 'tag-chrome-platform-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux:
platform/chrome: cros_ec_debugfs: detach log reader wq from devm
platform: chrome: Split trace include file
platform/chrome: cros_ec_typec: Update mux flags during partner removal
platform/chrome: cros_ec_typec: Configure muxes at start of port update
platform/chrome: cros_ec_typec: Get mux state inside configure_mux
platform/chrome: cros_ec_typec: Move mux flag checks
platform/chrome: cros_ec_typec: Check for EC device
platform/chrome: cros_ec_typec: Make try power role optional
MAINTAINERS: platform-chrome: Add new chrome-platform@lists.linux.dev list
This reverts commit 6d35d04a9e.
Both Gabriel and Borislav report that this commit casues a regression
with nbd:
sysfs: cannot create duplicate filename '/dev/block/43:0'
Revert it before 5.18-rc1 and we'll investigage this separately in
due time.
Link: https://lore.kernel.org/all/YkiJTnFOt9bTv6A2@zn.tnic/
Reported-by: Gabriel L. Somlo <somlo@cmu.edu>
Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
After being merged, user_events become more visible to a wider audience
that have concerns with the current API.
It is too late to fix this for this release, but instead of a full
revert, just mark it as BROKEN (which prevents it from being selected in
make config). Then we can work finding a better API. If that fails,
then it will need to be completely reverted.
To not have the code silently bitrot, still allow building it with
COMPILE_TEST.
And to prevent the uapi header from being installed, then later changed,
and then have an old distro user space see the old version, move the
header file out of the uapi directory.
Surround the include with CONFIG_COMPILE_TEST to the current location,
but when the BROKEN tag is taken off, it will use the uapi directory,
and fail to compile. This is a good way to remind us to move the header
back.
Link: https://lore.kernel.org/all/20220330155835.5e1f6669@gandalf.local.home
Link: https://lkml.kernel.org/r/20220330201755.29319-1-mathieu.desnoyers@efficios.com
Suggested-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ftrace_graph_is_dead() is used on hot paths, it just reads a variable
in memory and is not worth suffering function call constraints.
For instance, at entry of prepare_ftrace_return(), inlining it avoids
saving prepare_ftrace_return() parameters to stack and restoring them
after calling ftrace_graph_is_dead().
While at it using a static branch is even more performant and is
rather well adapted considering that the returned value will almost
never change.
Inline ftrace_graph_is_dead() and replace 'kill_ftrace_graph' bool
by a static branch.
The performance improvement is noticeable.
Link: https://lkml.kernel.org/r/e0411a6a0ed3eafff0ad2bc9cd4b0e202b4617df.1648623570.git.christophe.leroy@csgroup.eu
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When looking for implementation of different phases of the creation of the
TRACE_EVENT() macro, it is pretty useless when all helper macro
redefinitions are in files labeled "stageX_defines.h". Rename them to
state which phase the files are for. For instance, when looking for the
defines that are used to create the event fields, seeing
"stage4_event_fields.h" gives the developer a good idea that the defines
are in that file.
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
If apic_id is less than min, and (max - apic_id) is greater than
KVM_IPI_CLUSTER_SIZE, then the third check condition is satisfied but
the new apic_id does not fit the bitmask. In this case __send_ipi_mask
should send the IPI.
This is mostly theoretical, but it can happen if the apic_ids on three
iterations of the loop are for example 1, KVM_IPI_CLUSTER_SIZE, 0.
Fixes: aaffcfd1e8 ("KVM: X86: Implement PV IPIs in linux guest")
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Message-Id: <1646814944-51801-1-git-send-email-lirongqing@baidu.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
FNAME(cmpxchg_gpte) is an inefficient mess. It is at least decent if it
can go through get_user_pages_fast(), but if it cannot then it tries to
use memremap(); that is not just terribly slow, it is also wrong because
it assumes that the VM_PFNMAP VMA is contiguous.
The right way to do it would be to do the same thing as
hva_to_pfn_remapped() does since commit add6a0cd1c ("KVM: MMU: try to
fix up page faults before giving up", 2016-07-05), using follow_pte()
and fixup_user_fault() to determine the correct address to use for
memremap(). To do this, one could for example extract hva_to_pfn()
for use outside virt/kvm/kvm_main.c. But really there is no reason to
do that either, because there is already a perfectly valid address to
do the cmpxchg() on, only it is a userspace address. That means doing
user_access_begin()/user_access_end() and writing the code in assembly
to handle exceptions correctly. Worse, the guest PTE can be 8-byte
even on i686 so there is the extra complication of using cmpxchg8b to
account for. But at least it is an efficient mess.
(Thanks to Linus for suggesting improvement on the inline assembly).
Reported-by: Qiuhao Li <qiuhao@sysec.org>
Reported-by: Gaoning Pan <pgn@zju.edu.cn>
Reported-by: Yongkang Jia <kangel@zju.edu.cn>
Reported-by: syzbot+6cde2282daa792c49ab8@syzkaller.appspotmail.com
Debugged-by: Tadeusz Struk <tadeusz.struk@linaro.org>
Tested-by: Maxim Levitsky <mlevitsk@redhat.com>
Cc: stable@vger.kernel.org
Fixes: bd53cb35a3 ("X86/KVM: Handle PFNs outside of kernel reach when touching GPTEs")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When emulating exit from long mode, EFER_LMA is cleared with
vmx_set_efer(). This will already unset the VM_ENTRY_IA32E_MODE control
bit as requested by SDM, so there is no need to unset VM_ENTRY_IA32E_MODE
again in exit_lmode() explicitly. In case EFER isn't supported by
hardware, long mode isn't supported, so exit_lmode() cannot be reached.
Note that, thanks to the shadow controls mechanism, this change doesn't
eliminate vmread or vmwrite.
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Message-Id: <20220311102643.807507-3-zhenzhong.duan@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
vmx_set_efer() sets uret->data but, in fact if the value of uret->data
will be used vmx_setup_uret_msrs() will have rewritten it with the value
returned by update_transition_efer(). uret->data is consumed if and only
if uret->load_into_hardware is true, and vmx_setup_uret_msrs() takes care
of (a) updating uret->data before setting uret->load_into_hardware to true
(b) setting uret->load_into_hardware to false if uret->data isn't updated.
Opportunistically use "vmx" directly instead of redoing to_vmx().
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Message-Id: <20220311102643.807507-2-zhenzhong.duan@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
It was decided that when TSC scaling is not supported,
the virtual MSR_AMD64_TSC_RATIO should still have the default '1.0'
value.
However in this case kvm_max_tsc_scaling_ratio is not set,
which breaks various assumptions.
Fix this by always calculating kvm_max_tsc_scaling_ratio regardless of
host support. For consistency, do the same for VMX.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20220322172449.235575-8-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
