Linux kernel
============
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There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
code
Clone this repository
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Commit b9d79e4ca4ff ("fbmem: Mark proc_fb_seq_ops as __maybe_unused")
places the '__maybe_unused' in an entirely incorrect location between
the "struct" keyword and the structure name.
It's a wonder that gcc accepts that silently, but clang quite reasonably
warns about it:
drivers/video/fbdev/core/fbmem.c:736:21: warning: attribute declaration must precede definition [-Wignored-attributes]
static const struct __maybe_unused seq_operations proc_fb_seq_ops = {
^
Fix it.
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull drm fixes from Dave Airlie:
"Bit later than usual, I queued them all up on Friday then promptly
forgot to write the pull request email. This is mainly amdgpu fixes,
with some radeon/msm/fbdev and one i915 gvt fix thrown in.
amdgpu:
- MPO hang workaround
- Fix for concurrent VM flushes on vega/navi
- dcefclk is not adjustable on navi1x and newer
- MST HPD debugfs fix
- Suspend/resumes fixes
- Register VGA clients late in case driver fails to load
- Fix GEM leak in user framebuffer create
- Add support for polaris12 with 32 bit memory interface
- Fix duplicate cursor issue when using overlay
- Fix corruption with tiled surfaces on VCN3
- Add BO size and stride check to fix BO size verification
radeon:
- Fix off-by-one in power state parsing
- Fix possible memory leak in power state parsing
msm:
- NULL ptr dereference fix
fbdev:
- procfs disabled warning fix
i915:
- gvt: Fix a possible division by zero in vgpu display rate
calculation"
* tag 'drm-next-2021-05-10' of git://anongit.freedesktop.org/drm/drm:
drm/amdgpu: Use device specific BO size & stride check.
drm/amdgpu: Init GFX10_ADDR_CONFIG for VCN v3 in DPG mode.
drm/amd/pm: initialize variable
drm/radeon: Avoid power table parsing memory leaks
drm/radeon: Fix off-by-one power_state index heap overwrite
drm/amd/display: Fix two cursor duplication when using overlay
drm/amdgpu: add new MC firmware for Polaris12 32bit ASIC
fbmem: Mark proc_fb_seq_ops as __maybe_unused
drm/msm/dpu: Delete bonkers code
drm/i915/gvt: Prevent divided by zero when calculating refresh rate
amdgpu: fix GEM obj leak in amdgpu_display_user_framebuffer_create
drm/amdgpu: Register VGA clients after init can no longer fail
drm/amdgpu: Handling of amdgpu_device_resume return value for graceful teardown
drm/amdgpu: fix r initial values
drm/amd/display: fix wrong statement in mst hpd debugfs
amdgpu/pm: set pp_dpm_dcefclk to readonly on NAVI10 and newer gpus
amdgpu/pm: Prevent force of DCEFCLK on NAVI10 and SIENNA_CICHLID
drm/amdgpu: fix concurrent VM flushes on Vega/Navi v2
drm/amd/display: Reject non-zero src_y and src_x for video planes
Pull block fix from Jens Axboe:
"Turns out the bio max size change still has issues, so let's get it
reverted for 5.13-rc1. We'll shake out the issues there and defer it
to 5.14 instead"
* tag 'block-5.13-2021-05-09' of git://git.kernel.dk/linux-block:
Revert "bio: limit bio max size"
amd-drm-fixes-5.13-2021-05-05:
amdgpu:
- MPO hang workaround
- Fix for concurrent VM flushes on vega/navi
- dcefclk is not adjustable on navi1x and newer
- MST HPD debugfs fix
- Suspend/resumes fixes
- Register VGA clients late in case driver fails to load
- Fix GEM leak in user framebuffer create
- Add support for polaris12 with 32 bit memory interface
- Fix duplicate cursor issue when using overlay
- Fix corruption with tiled surfaces on VCN3
- Add BO size and stride check to fix BO size verification
radeon:
- Fix off-by-one in power state parsing
- Fix possible memory leak in power state parsing
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210506033929.3875-1-alexander.deucher@amd.com
Pull cifs fixes from Steve French:
"Three small SMB3 chmultichannel related changesets (also for stable)
from the SMB3 test event this week.
The other fixes are still in review/testing"
* tag '5.13-rc-smb3-part3' of git://git.samba.org/sfrench/cifs-2.6:
smb3: if max_channels set to more than one channel request multichannel
smb3: do not attempt multichannel to server which does not support it
smb3: when mounting with multichannel include it in requested capabilities
This reverts commit cd2c7545ae1beac3b6aae033c7f31193b3255946.
Alex reports that the commit causes corruption with LUKS on ext4. Revert
it for now so that this can be investigated properly.
Link: https://lore.kernel.org/linux-block/1620493841.bxdq8r5haw.none@localhost/
Reported-by: Alex Xu (Hello71) <alex_y_xu@yahoo.ca>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Two patches, one to fix a null pointer dereference in msm, and one to
fix an unused warning for in fbdev when PROCFS is disabled.
Signed-off-by: Dave Airlie <airlied@redhat.com>
# gpg: Signature made Thu 06 May 2021 22:26:35 AEST
# gpg: using ? key E3EF0D6F671851C5
# gpg: Can't check signature: unknown pubkey algorithm
From: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20210506122723.oqadel7oacazywij@gilmour
The builtin size check isn't really the right thing for AMD
modifiers due to a couple of reasons:
1) In the format structs we don't do set any of the tilesize / blocks
etc. to avoid having format arrays per modifier/GPU
2) The pitch on the main plane is pixel_pitch * bytes_per_pixel even
for tiled ...
3) The pitch for the DCC planes is really the pixel pitch of the main
surface that would be covered by it ...
Note that we only handle GFX9+ case but we do this after converting
the implicit modifier to an explicit modifier, so on GFX9+ all
framebuffers should be checked here.
There is a TODO about DCC alignment, but it isn't worse than before
and I'd need to dig a bunch into the specifics. Getting this out in
a reasonable timeframe to make sure it gets the appropriate testing
seemed more important.
Finally as I've found that debugging addfb2 failures is a pita I was
generous adding explicit error messages to every failure case.
Fixes: f258907fdd83 ("drm/amdgpu: Verify bo size can fit framebuffer size on init.")
Tested-by: Simon Ser <contact@emersion.fr>
Signed-off-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Pull scheduler fixes from Thomas Gleixner:
"A set of scheduler updates:
- Prevent PSI state corruption when schedule() races with cgroup
move.
A recent commit combined two PSI callbacks to reduce the number of
cgroup tree updates, but missed that schedule() can drop rq::lock
for load balancing, which opens the race window for
cgroup_move_task() which then observes half updated state.
The fix is to solely use task::ps_flags instead of looking at the
potentially mismatching scheduler state
- Prevent an out-of-bounds access in uclamp caused bu a rounding
division which can lead to an off-by-one error exceeding the
buckets array size.
- Prevent unfairness caused by missing load decay when a task is
attached to a cfs runqueue.
The old load of the task was attached to the runqueue and never
removed. Fix it by enforcing the load update through the hierarchy
for unthrottled run queue instances.
- A documentation fix fot the 'sched_verbose' command line option"
* tag 'sched-urgent-2021-05-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Fix unfairness caused by missing load decay
sched: Fix out-of-bound access in uclamp
psi: Fix psi state corruption when schedule() races with cgroup move
sched,doc: sched_debug_verbose cmdline should be sched_verbose
Mounting with "multichannel" is obviously implied if user requested
more than one channel on mount (ie mount parm max_channels>1).
Currently both have to be specified. Fix that so that if max_channels
is greater than 1 on mount, enable multichannel rather than silently
falling back to non-multichannel.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-By: Tom Talpey <tom@talpey.com>
Cc: <stable@vger.kernel.org> # v5.11+
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
We get a bug:
BUG: KASAN: slab-out-of-bounds in iov_iter_revert+0x11c/0x404
lib/iov_iter.c:1139
Read of size 8 at addr ffff0000d3fb11f8 by task
CPU: 0 PID: 12582 Comm: syz-executor.2 Not tainted
5.10.0-00843-g352c8610ccd2 #2
Hardware name: linux,dummy-virt (DT)
Call trace:
dump_backtrace+0x0/0x2d0 arch/arm64/kernel/stacktrace.c:132
show_stack+0x28/0x34 arch/arm64/kernel/stacktrace.c:196
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x110/0x164 lib/dump_stack.c:118
print_address_description+0x78/0x5c8 mm/kasan/report.c:385
__kasan_report mm/kasan/report.c:545 [inline]
kasan_report+0x148/0x1e4 mm/kasan/report.c:562
check_memory_region_inline mm/kasan/generic.c:183 [inline]
__asan_load8+0xb4/0xbc mm/kasan/generic.c:252
iov_iter_revert+0x11c/0x404 lib/iov_iter.c:1139
io_read fs/io_uring.c:3421 [inline]
io_issue_sqe+0x2344/0x2d64 fs/io_uring.c:5943
__io_queue_sqe+0x19c/0x520 fs/io_uring.c:6260
io_queue_sqe+0x2a4/0x590 fs/io_uring.c:6326
io_submit_sqe fs/io_uring.c:6395 [inline]
io_submit_sqes+0x4c0/0xa04 fs/io_uring.c:6624
__do_sys_io_uring_enter fs/io_uring.c:9013 [inline]
__se_sys_io_uring_enter fs/io_uring.c:8960 [inline]
__arm64_sys_io_uring_enter+0x190/0x708 fs/io_uring.c:8960
__invoke_syscall arch/arm64/kernel/syscall.c:36 [inline]
invoke_syscall arch/arm64/kernel/syscall.c:48 [inline]
el0_svc_common arch/arm64/kernel/syscall.c:158 [inline]
do_el0_svc+0x120/0x290 arch/arm64/kernel/syscall.c:227
el0_svc+0x1c/0x28 arch/arm64/kernel/entry-common.c:367
el0_sync_handler+0x98/0x170 arch/arm64/kernel/entry-common.c:383
el0_sync+0x140/0x180 arch/arm64/kernel/entry.S:670
Allocated by task 12570:
stack_trace_save+0x80/0xb8 kernel/stacktrace.c:121
kasan_save_stack mm/kasan/common.c:48 [inline]
kasan_set_track mm/kasan/common.c:56 [inline]
__kasan_kmalloc+0xdc/0x120 mm/kasan/common.c:461
kasan_kmalloc+0xc/0x14 mm/kasan/common.c:475
__kmalloc+0x23c/0x334 mm/slub.c:3970
kmalloc include/linux/slab.h:557 [inline]
__io_alloc_async_data+0x68/0x9c fs/io_uring.c:3210
io_setup_async_rw fs/io_uring.c:3229 [inline]
io_read fs/io_uring.c:3436 [inline]
io_issue_sqe+0x2954/0x2d64 fs/io_uring.c:5943
__io_queue_sqe+0x19c/0x520 fs/io_uring.c:6260
io_queue_sqe+0x2a4/0x590 fs/io_uring.c:6326
io_submit_sqe fs/io_uring.c:6395 [inline]
io_submit_sqes+0x4c0/0xa04 fs/io_uring.c:6624
__do_sys_io_uring_enter fs/io_uring.c:9013 [inline]
__se_sys_io_uring_enter fs/io_uring.c:8960 [inline]
__arm64_sys_io_uring_enter+0x190/0x708 fs/io_uring.c:8960
__invoke_syscall arch/arm64/kernel/syscall.c:36 [inline]
invoke_syscall arch/arm64/kernel/syscall.c:48 [inline]
el0_svc_common arch/arm64/kernel/syscall.c:158 [inline]
do_el0_svc+0x120/0x290 arch/arm64/kernel/syscall.c:227
el0_svc+0x1c/0x28 arch/arm64/kernel/entry-common.c:367
el0_sync_handler+0x98/0x170 arch/arm64/kernel/entry-common.c:383
el0_sync+0x140/0x180 arch/arm64/kernel/entry.S:670
Freed by task 12570:
stack_trace_save+0x80/0xb8 kernel/stacktrace.c:121
kasan_save_stack mm/kasan/common.c:48 [inline]
kasan_set_track+0x38/0x6c mm/kasan/common.c:56
kasan_set_free_info+0x20/0x40 mm/kasan/generic.c:355
__kasan_slab_free+0x124/0x150 mm/kasan/common.c:422
kasan_slab_free+0x10/0x1c mm/kasan/common.c:431
slab_free_hook mm/slub.c:1544 [inline]
slab_free_freelist_hook mm/slub.c:1577 [inline]
slab_free mm/slub.c:3142 [inline]
kfree+0x104/0x38c mm/slub.c:4124
io_dismantle_req fs/io_uring.c:1855 [inline]
__io_free_req+0x70/0x254 fs/io_uring.c:1867
io_put_req_find_next fs/io_uring.c:2173 [inline]
__io_queue_sqe+0x1fc/0x520 fs/io_uring.c:6279
__io_req_task_submit+0x154/0x21c fs/io_uring.c:2051
io_req_task_submit+0x2c/0x44 fs/io_uring.c:2063
task_work_run+0xdc/0x128 kernel/task_work.c:151
get_signal+0x6f8/0x980 kernel/signal.c:2562
do_signal+0x108/0x3a4 arch/arm64/kernel/signal.c:658
do_notify_resume+0xbc/0x25c arch/arm64/kernel/signal.c:722
work_pending+0xc/0x180
blkdev_read_iter can truncate iov_iter's count since the count + pos may
exceed the size of the blkdev. This will confuse io_read that we have
consume the iovec. And once we do the iov_iter_revert in io_read, we
will trigger the slab-out-of-bounds. Fix it by reexpand the count with
size has been truncated.
blkdev_write_iter can trigger the problem too.
Signed-off-by: yangerkun <yangerkun@huawei.com>
Acked-by: Pavel Begunkov <asml.silencec@gmail.com>
Link: https://lore.kernel.org/r/20210401071807.3328235-1-yangerkun@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
drm/i915 GVT fixes for v5.13-rc1:
- Fix a possible division by zero in vgpu display rate calculation
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/87wnsk16sa.fsf@intel.com
With CONFIG_PROC_FS=n and -Werror, 0-day reports:
drivers/video/fbdev/core/fbmem.c:736:36: error:
'proc_fb_seq_ops' defined but not used
Mark it as __maybe_unused.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210504142910.2084722-1-linux@roeck-us.net