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There is a race between capsnaps flush and removing the inode from
'mdsc->snap_flush_list' list:
== Thread A == == Thread B ==
ceph_queue_cap_snap()
-> allocate 'capsnapA'
->ihold('&ci->vfs_inode')
->add 'capsnapA' to 'ci->i_cap_snaps'
->add 'ci' to 'mdsc->snap_flush_list'
...
== Thread C ==
ceph_flush_snaps()
->__ceph_flush_snaps()
->__send_flush_snap()
handle_cap_flushsnap_ack()
->iput('&ci->vfs_inode')
this also will release 'ci'
...
== Thread D ==
ceph_handle_snap()
->flush_snaps()
->iterate 'mdsc->snap_flush_list'
->get the stale 'ci'
->remove 'ci' from ->ihold(&ci->vfs_inode) this
'mdsc->snap_flush_list' will WARNING
To fix this we will increase the inode's i_count ref when adding 'ci'
to the 'mdsc->snap_flush_list' list.
[ idryomov: need_put int -> bool ]
Cc: stable@vger.kernel.org
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2209299
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Milind Changire <mchangir@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Move capturing the snapshot context into the image request state
machine, after exclusive lock is ensured to be held for the duration of
dealing with the image request. This is needed to ensure correctness
of fast-diff states (OBJECT_EXISTS vs OBJECT_EXISTS_CLEAN) and object
deltas computed based off of them. Otherwise the object map that is
forked for the snapshot isn't guaranteed to accurately reflect the
contents of the snapshot when the snapshot is taken under I/O. This
breaks differential backup and snapshot-based mirroring use cases with
fast-diff enabled: since some object deltas may be incomplete, the
destination image may get corrupted.
Cc: stable@vger.kernel.org
Link: https://tracker.ceph.com/issues/61472
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Dongsheng Yang <dongsheng.yang@easystack.cn>
Move RBD_OBJ_FLAG_COPYUP_ENABLED flag setting into the object request
state machine to allow for the snapshot context to be captured in the
image request state machine rather than in rbd_queue_workfn().
Cc: stable@vger.kernel.org
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Dongsheng Yang <dongsheng.yang@easystack.cn>
Pull irq fix from Borislav Petkov:
- Fix open firmware quirks validation so that they don't get applied
wrongly
* tag 'irq_urgent_for_v6.4_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/gic: Correctly validate OF quirk descriptors
Pull media fixes from Mauro Carvalho Chehab:
"Some driver fixes:
- a regression fix for the verisilicon driver
- uvcvideo: don't expose unsupported video formats to userspace
- camss-video: don't zero subdev format after init
- mediatek: some fixes for 4K decoder formats
- fix a Sphinx build warning (missing doc for client_caps)
- some fixes for imx and atomisp staging drivers
And two CEC core fixes:
- don't set last_initiator if TX in progress
- disable adapter in cec_devnode_unregister"
* tag 'media/v6.4-4' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
media: uvcvideo: Don't expose unsupported formats to userspace
media: v4l2-subdev: Fix missing kerneldoc for client_caps
media: staging: media: imx: initialize hs_settle to avoid warning
media: v4l2-mc: Drop subdev check in v4l2_create_fwnode_links_to_pad()
media: staging: media: atomisp: init high & low vars
media: cec: core: don't set last_initiator if tx in progress
media: cec: core: disable adapter in cec_devnode_unregister
media: mediatek: vcodec: Only apply 4K frame sizes on decoder formats
media: camss: camss-video: Don't zero subdev format again after initialization
media: verisilicon: Additional fix for the crash when opening the driver
Pull an irqchip fix from Marc Zyngier:
- Fix regression introduced by the Mediatek workaround.
Link: https://lore.kernel.org/lkml/20230531160549.433528-1-maz@kernel.org
Pull char/misc driver fixes from Greg KH:
"Here are a bunch of tiny char/misc/other driver fixes for 6.4-rc5 that
resolve a number of reported issues. Included in here are:
- iio driver fixes
- fpga driver fixes
- test_firmware bugfixes
- fastrpc driver tiny bugfixes
- MAINTAINERS file updates for some subsystems
All of these have been in linux-next this past week with no reported
issues"
* tag 'char-misc-6.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (34 commits)
test_firmware: fix the memory leak of the allocated firmware buffer
test_firmware: fix a memory leak with reqs buffer
test_firmware: prevent race conditions by a correct implementation of locking
firmware_loader: Fix a NULL vs IS_ERR() check
MAINTAINERS: Vaibhav Gupta is the new ipack maintainer
dt-bindings: fpga: replace Ivan Bornyakov maintainership
MAINTAINERS: update Microchip MPF FPGA reviewers
misc: fastrpc: reject new invocations during device removal
misc: fastrpc: return -EPIPE to invocations on device removal
misc: fastrpc: Reassign memory ownership only for remote heap
misc: fastrpc: Pass proper scm arguments for secure map request
iio: imu: inv_icm42600: fix timestamp reset
iio: adc: ad_sigma_delta: Fix IRQ issue by setting IRQ_DISABLE_UNLAZY flag
dt-bindings: iio: adc: renesas,rcar-gyroadc: Fix adi,ad7476 compatible value
iio: dac: mcp4725: Fix i2c_master_send() return value handling
iio: accel: kx022a fix irq getting
iio: bu27034: Ensure reset is written
iio: dac: build ad5758 driver when AD5758 is selected
iio: addac: ad74413: fix resistance input processing
iio: light: vcnl4035: fixed chip ID check
...
When the uvcvideo driver encounters a format descriptor with an unknown
format GUID, it creates a corresponding struct uvc_format instance with
the fcc field set to 0. Since commit 50459f103edf ("media: uvcvideo:
Remove format descriptions"), the driver relies on the V4L2 core to
provide the format description string, which the V4L2 core can't do
without a valid 4CC. This triggers a WARN_ON.
As a format with a zero 4CC can't be selected, it is unusable for
applications. Ignore the format completely without creating a uvc_format
instance, which fixes the warning.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217252
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2180107
Fixes: 50459f103edf ("media: uvcvideo: Remove format descriptions")
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Ricardo Ribalda <ribalda@chromium.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Pull irqchip fixes from Marc Zyngier:
- MIPS GIC fixes for issues that could result in either
loss of state in the interrupt controller, or a deadlock
- Workaround for Mediatek Chromebooks that only save/restore
partial state when turning the GIC redistributors off,
resulting if fireworks if Linux uses interrupt priorities
for pseudo-NMIs
- Fix the MBIGEN error handling on init
- Mark meson-gpio OF data structures as __maybe_unused,
avoiding compilation warnings on non-OF setups
Link: https://lore.kernel.org/lkml/20230521101812.2520740-1-maz@kernel.org
When checking for OF quirks, make sure either 'compatible' or 'property'
is set, and give up otherwise.
This avoids non-OF quirks being randomly applied as they don't have any
of the OF data that need checking.
Cc: Douglas Anderson <dianders@chromium.org>
Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Fixes: 44bd78dd2b88 ("irqchip/gic-v3: Disable pseudo NMIs on Mediatek devices w/ firmware issues")
Signed-off-by: Marc Zyngier <maz@kernel.org>
Pull driver core fixes from Greg KH:
"Here are two small driver core cacheinfo fixes for 6.4-rc5 that
resolve a number of reported issues with that file. These changes have
been in linux-next this past week with no reported problems"
* tag 'driver-core-6.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
drivers: base: cacheinfo: Update cpu_map_populated during CPU Hotplug
drivers: base: cacheinfo: Fix shared_cpu_map changes in event of CPU hotplug
The following kernel memory leak was noticed after running
tools/testing/selftests/firmware/fw_run_tests.sh:
[root@pc-mtodorov firmware]# cat /sys/kernel/debug/kmemleak
.
.
.
unreferenced object 0xffff955389bc3400 (size 1024):
comm "test_firmware-0", pid 5451, jiffies 4294944822 (age 65.652s)
hex dump (first 32 bytes):
47 48 34 35 36 37 0a 00 00 00 00 00 00 00 00 00 GH4567..........
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff962f5dec>] slab_post_alloc_hook+0x8c/0x3c0
[<ffffffff962fcca4>] __kmem_cache_alloc_node+0x184/0x240
[<ffffffff962704de>] kmalloc_trace+0x2e/0xc0
[<ffffffff9665b42d>] test_fw_run_batch_request+0x9d/0x180
[<ffffffff95fd813b>] kthread+0x10b/0x140
[<ffffffff95e033e9>] ret_from_fork+0x29/0x50
unreferenced object 0xffff9553c334b400 (size 1024):
comm "test_firmware-1", pid 5452, jiffies 4294944822 (age 65.652s)
hex dump (first 32 bytes):
47 48 34 35 36 37 0a 00 00 00 00 00 00 00 00 00 GH4567..........
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff962f5dec>] slab_post_alloc_hook+0x8c/0x3c0
[<ffffffff962fcca4>] __kmem_cache_alloc_node+0x184/0x240
[<ffffffff962704de>] kmalloc_trace+0x2e/0xc0
[<ffffffff9665b42d>] test_fw_run_batch_request+0x9d/0x180
[<ffffffff95fd813b>] kthread+0x10b/0x140
[<ffffffff95e033e9>] ret_from_fork+0x29/0x50
unreferenced object 0xffff9553c334f000 (size 1024):
comm "test_firmware-2", pid 5453, jiffies 4294944822 (age 65.652s)
hex dump (first 32 bytes):
47 48 34 35 36 37 0a 00 00 00 00 00 00 00 00 00 GH4567..........
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff962f5dec>] slab_post_alloc_hook+0x8c/0x3c0
[<ffffffff962fcca4>] __kmem_cache_alloc_node+0x184/0x240
[<ffffffff962704de>] kmalloc_trace+0x2e/0xc0
[<ffffffff9665b42d>] test_fw_run_batch_request+0x9d/0x180
[<ffffffff95fd813b>] kthread+0x10b/0x140
[<ffffffff95e033e9>] ret_from_fork+0x29/0x50
unreferenced object 0xffff9553c3348400 (size 1024):
comm "test_firmware-3", pid 5454, jiffies 4294944822 (age 65.652s)
hex dump (first 32 bytes):
47 48 34 35 36 37 0a 00 00 00 00 00 00 00 00 00 GH4567..........
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff962f5dec>] slab_post_alloc_hook+0x8c/0x3c0
[<ffffffff962fcca4>] __kmem_cache_alloc_node+0x184/0x240
[<ffffffff962704de>] kmalloc_trace+0x2e/0xc0
[<ffffffff9665b42d>] test_fw_run_batch_request+0x9d/0x180
[<ffffffff95fd813b>] kthread+0x10b/0x140
[<ffffffff95e033e9>] ret_from_fork+0x29/0x50
[root@pc-mtodorov firmware]#
Note that the size 1024 corresponds to the size of the test firmware
buffer. The actual number of the buffers leaked is around 70-110,
depending on the test run.
The cause of the leak is the following:
request_partial_firmware_into_buf() and request_firmware_into_buf()
provided firmware buffer isn't released on release_firmware(), we
have allocated it and we are responsible for deallocating it manually.
This is introduced in a number of context where previously only
release_firmware() was called, which was insufficient.
Reported-by: Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>
Fixes: 7feebfa487b92 ("test_firmware: add support for request_firmware_into_buf")
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Dan Carpenter <error27@gmail.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Russ Weight <russell.h.weight@intel.com>
Cc: Tianfei zhang <tianfei.zhang@intel.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Zhengchao Shao <shaozhengchao@huawei.com>
Cc: Colin Ian King <colin.i.king@gmail.com>
Cc: linux-kernel@vger.kernel.org
Cc: Kees Cook <keescook@chromium.org>
Cc: Scott Branden <sbranden@broadcom.com>
Cc: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: linux-kselftest@vger.kernel.org
Cc: stable@vger.kernel.org # v5.4
Signed-off-by: Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>
Link: https://lore.kernel.org/r/20230509084746.48259-3-mirsad.todorovac@alu.unizg.hr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add missing kernel doc for the new 'client_caps' field in struct
v4l2_subdev_fh.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Fixes: f57fa2959244 ("media: v4l2-subdev: Add new ioctl for client capabilities")
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
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