Some of the scheduling tracepoints allow the perf_tp_event
code to write to ring buffer under different cpu than the
code is running on.
This results in corrupted ring buffer data demonstrated in
following perf commands:
# perf record -e 'sched:sched_switch,sched:sched_wakeup' perf bench sched messaging
# Running 'sched/messaging' benchmark:
# 20 sender and receiver processes per group
# 10 groups == 400 processes run
Total time: 0.383 [sec]
[ perf record: Woken up 8 times to write data ]
0x42b890 [0]: failed to process type: -1765585640
[ perf record: Captured and wrote 4.825 MB perf.data (29669 samples) ]
# perf report --stdio
0x42b890 [0]: failed to process type: -1765585640
The reason for the corruption are some of the scheduling tracepoints,
that have __perf_task dfined and thus allow to store data to another
cpu ring buffer:
sched_waking
sched_wakeup
sched_wakeup_new
sched_stat_wait
sched_stat_sleep
sched_stat_iowait
sched_stat_blocked
The perf_tp_event function first store samples for current cpu
related events defined for tracepoint:
hlist_for_each_entry_rcu(event, head, hlist_entry)
perf_swevent_event(event, count, &data, regs);
And then iterates events of the 'task' and store the sample
for any task's event that passes tracepoint checks:
ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]);
list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
if (event->attr.type != PERF_TYPE_TRACEPOINT)
continue;
if (event->attr.config != entry->type)
continue;
perf_swevent_event(event, count, &data, regs);
}
Above code can race with same code running on another cpu,
ending up with 2 cpus trying to store under the same ring
buffer, which is specifically not allowed.
This patch prevents the problem, by allowing only events with the same
current cpu to receive the event.
NOTE: this requires the use of (per-task-)per-cpu buffers for this
feature to work; perf-record does this.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
[peterz: small edits to Changelog]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrew Vagin <avagin@openvz.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: e6dab5ffab ("perf/trace: Add ability to set a target task for events")
Link: http://lkml.kernel.org/r/20180923161343.GB15054@krava
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Jens writes:
"Block fixes for 4.19-rc6
A set of fixes that should go into this release. This pull request
contains:
- A fix (hopefully) for the persistent grants for xen-blkfront. A
previous fix from this series wasn't complete, hence reverted, and
this one should hopefully be it. (Boris Ostrovsky)
- Fix for an elevator drain warning with SMR devices, which is
triggered when you switch schedulers (Damien)
- bcache deadlock fix (Guoju Fang)
- Fix for the block unplug tracepoint, which has had the
timer/explicit flag reverted since 4.11 (Ilya)
- Fix a regression in this series where the blk-mq timeout hook is
invoked with the RCU read lock held, hence preventing it from
blocking (Keith)
- NVMe pull from Christoph, with a single multipath fix (Susobhan Dey)"
* tag 'for-linus-20180929' of git://git.kernel.dk/linux-block:
xen/blkfront: correct purging of persistent grants
Revert "xen/blkfront: When purging persistent grants, keep them in the buffer"
blk-mq: I/O and timer unplugs are inverted in blktrace
bcache: add separate workqueue for journal_write to avoid deadlock
xen/blkfront: When purging persistent grants, keep them in the buffer
block: fix deadline elevator drain for zoned block devices
blk-mq: Allow blocking queue tag iter callbacks
nvme: properly propagate errors in nvme_mpath_init
Thomas writes:
"A single fix for the AMD memory encryption boot code so it does not
read random garbage instead of the cached encryption bit when a kexec
kernel is allocated above the 32bit address limit."
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/boot: Fix kexec booting failure in the SEV bit detection code
Thomas writes:
"Three small fixes for clocksource drivers:
- Proper error handling in the Atmel PIT driver
- Add CLOCK_SOURCE_SUSPEND_NONSTOP for TI SoCs so suspend works again
- Fix the next event function for Facebook Backpack-CMM BMC chips so
usleep(100) doesnt sleep several milliseconds"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
clocksource/drivers/timer-atmel-pit: Properly handle error cases
clocksource/drivers/fttmr010: Fix set_next_event handler
clocksource/drivers/ti-32k: Add CLOCK_SOURCE_SUSPEND_NONSTOP flag for non-am43 SoCs
Thomas writes:
"A single fix for a missing sanity check when a pinned event is tried
to be read on the wrong CPU due to a legit event scheduling failure."
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Add sanity check to deal with pinned event failure
Rafael writes:
"Power management fix for 4.19-rc6
Fix incorrect __init and __exit annotations in the Qualcomm
Kryo cpufreq driver (Nathan Chancellor)."
* tag 'pm-4.19-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
cpufreq: qcom-kryo: Fix section annotations
There is currently a warning when building the Kryo cpufreq driver into
the kernel image:
WARNING: vmlinux.o(.text+0x8aa424): Section mismatch in reference from
the function qcom_cpufreq_kryo_probe() to the function
.init.text:qcom_cpufreq_kryo_get_msm_id()
The function qcom_cpufreq_kryo_probe() references
the function __init qcom_cpufreq_kryo_get_msm_id().
This is often because qcom_cpufreq_kryo_probe lacks a __init
annotation or the annotation of qcom_cpufreq_kryo_get_msm_id is wrong.
Remove the '__init' annotation from qcom_cpufreq_kryo_get_msm_id
so that there is no more mismatch warning.
Additionally, Nick noticed that the remove function was marked as
'__init' when it should really be marked as '__exit'.
Fixes: 46e2856b8e (cpufreq: Add Kryo CPU scaling driver)
Fixes: 5ad7346b4a (cpufreq: kryo: Add module remove and exit)
Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 4.18+ <stable@vger.kernel.org> # 4.18+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Christoph writes:
"dma mapping fix for 4.19-rc6
fix a missing Kconfig symbol for commits introduced in 4.19-rc"
* tag 'dma-mapping-4.19-3' of git://git.infradead.org/users/hch/dma-mapping:
dma-mapping: add the missing ARCH_HAS_SYNC_DMA_FOR_CPU_ALL declaration
Dmitry writes:
"Input updates for v4.19-rc5
Just a few driver fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: uinput - allow for max == min during input_absinfo validation
Input: elantech - enable middle button of touchpad on ThinkPad P72
Input: atakbd - fix Atari CapsLock behaviour
Input: atakbd - fix Atari keymap
Input: egalax_ts - add system wakeup support
Input: gpio-keys - fix a documentation index issue
Mark writes:
"spi: Fixes for v4.19
Quite a few fixes for the Renesas drivers in here, plus a fix for the
Tegra driver and some documentation fixes for the recently added
spi-mem code. The Tegra fix is relatively large but fairly
straightforward and mechanical, it runs on probe so it's been
reasonably well covered in -next testing."
* tag 'spi-fix-v4.19-rc5' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
spi: spi-mem: Move the DMA-able constraint doc to the kerneldoc header
spi: spi-mem: Add missing description for data.nbytes field
spi: rspi: Fix interrupted DMA transfers
spi: rspi: Fix invalid SPI use during system suspend
spi: sh-msiof: Fix handling of write value for SISTR register
spi: sh-msiof: Fix invalid SPI use during system suspend
spi: gpio: Fix copy-and-paste error
spi: tegra20-slink: explicitly enable/disable clock
Mark writes:
"regulator: Fixes for 4.19
A collection of fairly minor bug fixes here, a couple of driver
specific ones plus two core fixes. There's one fix for the new
suspend state code which fixes some confusion with constant values
that are supposed to indicate noop operation and another fixing a
race condition with the creation of sysfs files on new regulators."
* tag 'regulator-v4.19-rc5' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
regulator: fix crash caused by null driver data
regulator: Fix 'do-nothing' value for regulators without suspend state
regulator: da9063: fix DT probing with constraints
regulator: bd71837: Disable voltage monitoring for LDO3/4
Michael writes:
"powerpc fixes for 4.19 #3
A reasonably big batch of fixes due to me being away for a few weeks.
A fix for the TM emulation support on Power9, which could result in
corrupting the guest r11 when running under KVM.
Two fixes to the TM code which could lead to userspace GPR corruption
if we take an SLB miss at exactly the wrong time.
Our dynamic patching code had a bug that meant we could patch freed
__init text, which could lead to corrupting userspace memory.
csum_ipv6_magic() didn't work on little endian platforms since we
optimised it recently.
A fix for an endian bug when reading a device tree property telling
us how many storage keys the machine has available.
Fix a crash seen on some configurations of PowerVM when migrating the
partition from one machine to another.
A fix for a regression in the setup of our CPU to NUMA node mapping
in KVM guests.
A fix to our selftest Makefiles to make them work since a recent
change to the shared Makefile logic."
* tag 'powerpc-4.19-3' of https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
selftests/powerpc: Fix Makefiles for headers_install change
powerpc/numa: Use associativity if VPHN hcall is successful
powerpc/tm: Avoid possible userspace r1 corruption on reclaim
powerpc/tm: Fix userspace r13 corruption
powerpc/pseries: Fix unitialized timer reset on migration
powerpc/pkeys: Fix reading of ibm, processor-storage-keys property
powerpc: fix csum_ipv6_magic() on little endian platforms
powerpc/powernv/ioda2: Reduce upper limit for DMA window size (again)
powerpc: Avoid code patching freed init sections
KVM: PPC: Book3S HV: Fix guest r11 corruption with POWER9 TM workarounds
The success of a cache pseudo-locked region is measured using
performance monitoring events that are programmed directly at the time
the user requests a measurement.
Modifying the performance event registers directly is not appropriate
since it circumvents the in-kernel perf infrastructure that exists to
manage these resources and provide resource arbitration to the
performance monitoring hardware.
The cache pseudo-locking measurements are modified to use the in-kernel
perf infrastructure. Performance events are created and validated with
the appropriate perf API. The performance counters are still read as
directly as possible to avoid the additional cache hits. This is
done safely by first ensuring with the perf API that the counters have
been programmed correctly and only accessing the counters in an
interrupt disabled section where they are not able to be moved.
As part of the transition to the in-kernel perf infrastructure the L2
and L3 measurements are split into two separate measurements that can
be triggered independently. This separation prevents additional cache
misses incurred during the extra testing code used to decide if a
L2 and/or L3 measurement should be made.
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: fenghua.yu@intel.com
Cc: tony.luck@intel.com
Cc: peterz@infradead.org
Cc: acme@kernel.org
Cc: gavin.hindman@intel.com
Cc: jithu.joseph@intel.com
Cc: dave.hansen@intel.com
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/fc24e728b446404f42c78573c506e98cd0599873.1537468643.git.reinette.chatre@intel.com
A perf event has many attributes that are maintained in a separate
structure that should be provided when a new perf_event is created.
In preparation for the transition to perf_events the required attribute
structures are created for all the events that may be used in the
measurements. Most attributes for all the events are identical. The
actual configuration, what specifies what needs to be measured, is what
will be different between the events used. This configuration needs to
be done with X86_CONFIG that cannot be used as part of the designated
initializers used here, this will be introduced later.
Although they do look identical at this time the attribute structures
needs to be maintained separately since a perf_event will maintain a
pointer to its unique attributes.
In support of patch testing the new structs are given the unused attribute
until their use in later patches.
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: fenghua.yu@intel.com
Cc: tony.luck@intel.com
Cc: acme@kernel.org
Cc: gavin.hindman@intel.com
Cc: jithu.joseph@intel.com
Cc: dave.hansen@intel.com
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/1822f6164e221a497648d108913d056ab675d5d0.1537377064.git.reinette.chatre@intel.com
Local register variables were used in an effort to improve the
accuracy of the measurement of cache residency of a pseudo-locked
region. This was done to ensure that only the cache residency of
the memory is measured and not the cache residency of the variables
used to perform the measurement.
While local register variables do accomplish the goal they do require
significant care since different architectures have different registers
available. Local register variables also cannot be used with valuable
developer tools like KASAN.
Significant testing has shown that similar accuracy in measurement
results can be obtained by replacing local register variables with
regular local variables.
Make use of local variables in the critical code but do so with
READ_ONCE() to prevent the compiler from merging or refetching reads.
Ensure these variables are initialized before the measurement starts,
and ensure it is only the local variables that are accessed during
the measurement.
With the removal of the local register variables and using READ_ONCE()
there is no longer a motivation for using a direct wrmsr call (that
avoids the additional tracing code that may clobber the local register
variables).
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: fenghua.yu@intel.com
Cc: tony.luck@intel.com
Cc: acme@kernel.org
Cc: gavin.hindman@intel.com
Cc: jithu.joseph@intel.com
Cc: dave.hansen@intel.com
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/f430f57347414e0691765d92b144758ab93d8407.1537377064.git.reinette.chatre@intel.com
Dave writes:
"drm fixes for 4.19-rc6
Looks like a pretty normal week for graphics,
core: syncobj fix, panel link regression revert
amd: suspend/resume fixes, EDID emulation fix
mali-dp: NV12 writeback and vblank reset fixes
etnaviv: DMA setup fix"
* tag 'drm-fixes-2018-09-28' of git://anongit.freedesktop.org/drm/drm:
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"
drm/syncobj: Don't leak fences when WAIT_FOR_SUBMIT is set
drm/malidp: Fix writeback in NV12
drm: mali-dp: Call drm_crtc_vblank_reset on device init
drm/etnaviv: add DMA configuration for etnaviv platform device
Palmer writes:
"A Single RISC-V Update for 4.19-rc6
The Debian guys have been pushing on our port and found some
unversioned symbols leaking into modules. This PR contains a single
fix for that issue."
* tag 'riscv-for-linus-4.19-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux:
RISC-V: include linux/ftrace.h in asm-prototypes.h
Commit a46b53672b ("xen/blkfront: cleanup
stale persistent grants") introduced a regression as purged persistent
grants were not pu into the list of free grants again. Correct that.
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit b2d35fa5fc ("selftests: add headers_install to lib.mk")
introduced a requirement that Makefiles more than one level below the
selftests directory need to define top_srcdir, but it didn't update
any of the powerpc Makefiles.
This broke building all the powerpc selftests with eg:
make[1]: Entering directory '/src/linux/tools/testing/selftests/powerpc'
BUILD_TARGET=/src/linux/tools/testing/selftests/powerpc/alignment; mkdir -p $BUILD_TARGET; make OUTPUT=$BUILD_TARGET -k -C alignment all
make[2]: Entering directory '/src/linux/tools/testing/selftests/powerpc/alignment'
../../lib.mk:20: ../../../../scripts/subarch.include: No such file or directory
make[2]: *** No rule to make target '../../../../scripts/subarch.include'.
make[2]: Failed to remake makefile '../../../../scripts/subarch.include'.
Makefile:38: recipe for target 'alignment' failed
Fix it by setting top_srcdir in the affected Makefiles.
Fixes: b2d35fa5fc ("selftests: add headers_install to lib.mk")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Jason writes:
"Second RDMA rc pull request
- Fix a long standing race bug when destroying comp_event file descriptors
- srp, hfi1, bnxt_re: Various driver crashes from missing validation
and other cases
- Fixes for regressions in patches merged this window in the gid
cache, devx, ucma and uapi."
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
RDMA/core: Set right entry state before releasing reference
IB/mlx5: Destroy the DEVX object upon error flow
IB/uverbs: Free uapi on destroy
RDMA/bnxt_re: Fix system crash during RDMA resource initialization
IB/hfi1: Fix destroy_qp hang after a link down
IB/hfi1: Fix context recovery when PBC has an UnsupportedVL
IB/hfi1: Invalid user input can result in crash
IB/hfi1: Fix SL array bounds check
RDMA/uverbs: Fix validity check for modify QP
IB/srp: Avoid that sg_reset -d ${srp_device} triggers an infinite loop
ucma: fix a use-after-free in ucma_resolve_ip()
RDMA/uverbs: Atomically flush and mark closed the comp event queue
cxgb4: fix abort_req_rss6 struct
Jan writes:
"an ext2 patch fixing fsync(2) for DAX mounts."
* tag 'for_v4.19-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
ext2, dax: set ext2_dax_aops for dax files
trace_block_unplug() takes true for explicit unplugs and false for
implicit unplugs. schedule() unplugs are implicit and should be
reported as timer unplugs. While correct in the legacy code, this has
been inverted in blk-mq since 4.11.
Cc: stable@vger.kernel.org
Fixes: bd166ef183 ("blk-mq-sched: add framework for MQ capable IO schedulers")
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit
1958b5fc40 ("x86/boot: Add early boot support when running with SEV active")
can occasionally cause system resets when kexec-ing a second kernel even
if SEV is not active.
That's because get_sev_encryption_bit() uses 32-bit rIP-relative
addressing to read the value of enc_bit - a variable which caches a
previously detected encryption bit position - but kexec may allocate
the early boot code to a higher location, beyond the 32-bit addressing
limit.
In this case, garbage will be read and get_sev_encryption_bit() will
return the wrong value, leading to accessing memory with the wrong
encryption setting.
Therefore, remove enc_bit, and thus get rid of the need to do 32-bit
rIP-relative addressing in the first place.
[ bp: massage commit message heavily. ]
Fixes: 1958b5fc40 ("x86/boot: Add early boot support when running with SEV active")
Suggested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Kairui Song <kasong@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: linux-kernel@vger.kernel.org
Cc: tglx@linutronix.de
Cc: mingo@redhat.com
Cc: hpa@zytor.com
Cc: brijesh.singh@amd.com
Cc: kexec@lists.infradead.org
Cc: dyoung@redhat.com
Cc: bhe@redhat.com
Cc: ghook@redhat.com
Link: https://lkml.kernel.org/r/20180927123845.32052-1-kasong@redhat.com
After write SSD completed, bcache schedules journal_write work to
system_wq, which is a public workqueue in system, without WQ_MEM_RECLAIM
flag. system_wq is also a bound wq, and there may be no idle kworker on
current processor. Creating a new kworker may unfortunately need to
reclaim memory first, by shrinking cache and slab used by vfs, which
depends on bcache device. That's a deadlock.
This patch create a new workqueue for journal_write with WQ_MEM_RECLAIM
flag. It's rescuer thread will work to avoid the deadlock.
Signed-off-by: Guoju Fang <fangguoju@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[Why]
EDID emulation didn't work properly for linux, as we stop programming
if nothing is connected physically.
[How]
We get a flag from DRM when we want to do edid emulation. We check if
this flag is true and nothing is connected physically, if so we only
program the front end using VIRTUAL_SIGNAL.
Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
There have been a few reports of Vega10 display remaining blank
after S3 resume. The regression is caused by workaround for mode
change on Vega10 - skip set_bandwidth if stream count is 0.
As a result we skipped dispclk reset on suspend, thus on resume
we may skip the clock update assuming it hasn't been changed.
On some systems it causes display blank or 'out of range'.
[How]
Revert "drm/amd/display: Fix Vega10 black screen after mode change"
Verified that it hadn't cause mode change regression.
Signed-off-by: Roman Li <Roman.Li@amd.com>
Reviewed-by: Sun peng Li <Sunpeng.Li@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
The vce cancel_delayed_work_sync never be called.
driver call the function in error path.
This caused the A+A suspend hang when runtime pm enebled.
As we will visit the smu in the idle queue. this will cause
smu hang because the dgpu has been suspend, and the dgpu also
will be waked up. As the smu has been hang, so the dgpu resume
will failed.
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Feifei Xu <Feifei.Xu@amd.com>
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
This reverts commit 0c08754b59.
commit 0c08754b59
("drm/panel: Add device_link from panel device to DRM device")
creates a circular dependency under these circumstances:
1. The panel depends on dsi-host because it is MIPI-DSI child
device.
2. dsi-host depends on the drm parent device (connector->dev->dev)
this should be allowed.
3. drm parent dev (connector->dev->dev) depends on the panel
after this patch.
This makes the dependency circular and while it appears it
does not affect any in-tree drivers (they do not seem to have
dsi hosts depending on the same parent device) this does not
seem right.
As noted in a response from Andrzej Hajda, the intent is
likely to make the panel dependent on the DRM device
(connector->dev) not its parent. But we have no way of
doing that since the DRM device doesn't contain any
struct device on its own (arguably it should).
Revert this until a proper approach is figured out.
Cc: Jyri Sarha <jsarha@ti.com>
Cc: Eric Anholt <eric@anholt.net>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180927124130.9102-1-linus.walleij@linaro.org
Commit a46b53672b ("xen/blkfront: cleanup stale persistent grants")
added support for purging persistent grants when they are not in use. As
part of the purge, the grants were removed from the grant buffer, This
eventually causes the buffer to become empty, with BUG_ON triggered in
get_free_grant(). This can be observed even on an idle system, within
20-30 minutes.
We should keep the grants in the buffer when purging, and only free the
grant ref.
Fixes: a46b53672b ("xen/blkfront: cleanup stale persistent grants")
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The smatch utility reports a possible leak:
smatch warnings:
drivers/clocksource/timer-atmel-pit.c:183 at91sam926x_pit_dt_init() warn: possible memory leak of 'data'
Ensure data is freed before exiting with an error.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
When the deadline scheduler is used with a zoned block device, writes
to a zone will be dispatched one at a time. This causes the warning
message:
deadline: forced dispatching is broken (nr_sorted=X), please report this
to be displayed when switching to another elevator with the legacy I/O
path while write requests to a zone are being retained in the scheduler
queue.
Prevent this message from being displayed when executing
elv_drain_elevator() for a zoned block device. __blk_drain_queue() will
loop until all writes are dispatched and completed, resulting in the
desired elevator queue drain without extensive modifications to the
deadline code itself to handle forced-dispatch calls.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Fixes: 8dc8146f9c ("deadline-iosched: Introduce zone locking support")
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
HP 6730b laptop has an ethernet NIC connected to one of the PCIe root
ports. The root ports themselves are native PCIe hotplug capable. Now,
during boot after PCI devices are scanned the BIOS triggers ACPI bus check
directly to the NIC:
ACPI: \_SB_.PCI0.RP06.NIC_: Bus check in hotplug_event()
It is not clear why it is sending bus check but regardless the ACPI hotplug
notify handler calls enable_slot() directly (instead of going through
acpiphp_check_bridge() as there is no bridge), which ends up handling
special case for non-hotplug bridges with native PCIe hotplug. This
results a crash of some kind but the reporter only sees black screen so it
is hard to figure out the exact spot and what actually happens. Based on
a few fix proposals it was tracked to crash somewhere inside
pci_assign_unassigned_bridge_resources().
In any case we should not really be in that special branch at all because
the ACPI notify happened to a slot that is not a PCI bridge (it is just a
regular PCI device).
Fix this so that we only go to that special branch if we are calling
enable_slot() for a bridge (e.g., the ACPI notification was for the
bridge).
Link: https://bugzilla.kernel.org/show_bug.cgi?id=201127
Fixes: 84c8b58ed3 ("ACPI / hotplug / PCI: Don't scan bridges managed by native hotplug")
Reported-by: Peter Anemone <peter.anemone@gmail.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
CC: stable@vger.kernel.org # v4.18+
