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John Stultz 5be9407b41 sound/virtio: Fix cancel_sync warnings on uninitialized work_structs
[ Upstream commit 3c7df2e27346eb40a0e86230db1ccab195c97cfe ]

Betty reported hitting the following warning:

[    8.709131][  T221] WARNING: CPU: 2 PID: 221 at kernel/workqueue.c:4182
...
[    8.713282][  T221] Call trace:
[    8.713365][  T221]  __flush_work+0x8d0/0x914
[    8.713468][  T221]  __cancel_work_sync+0xac/0xfc
[    8.713570][  T221]  cancel_work_sync+0x24/0x34
[    8.713667][  T221]  virtsnd_remove+0xa8/0xf8 [virtio_snd ab15f34d0dd772f6d11327e08a81d46dc9c36276]
[    8.713868][  T221]  virtsnd_probe+0x48c/0x664 [virtio_snd ab15f34d0dd772f6d11327e08a81d46dc9c36276]
[    8.714035][  T221]  virtio_dev_probe+0x28c/0x390
[    8.714139][  T221]  really_probe+0x1bc/0x4c8
...

It seems we're hitting the error path in virtsnd_probe(), which
triggers a virtsnd_remove() which iterates over the substreams
calling cancel_work_sync() on the elapsed_period work_struct.

Looking at the code, from earlier in:
virtsnd_probe()->virtsnd_build_devs()->virtsnd_pcm_parse_cfg()

We set snd->nsubstreams, allocate the snd->substreams, and if
we then hit an error on the info allocation or something in
virtsnd_ctl_query_info() fails, we will exit without having
initialized the elapsed_period work_struct.

When that error path unwinds we then call virtsnd_remove()
which as long as the substreams array is allocated, will iterate
through calling cancel_work_sync() on the uninitialized work
struct hitting this warning.

Takashi Iwai suggested this fix, which initializes the substreams
structure right after allocation, so that if we hit the error
paths we avoid trying to cleanup uninitialized data.

Note: I have not yet managed to reproduce the issue myself, so
this patch has had limited testing.

Feedback or thoughts would be appreciated!

Cc: Anton Yakovlev <anton.yakovlev@opensynergy.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.com>
Cc: virtualization@lists.linux.dev
Cc: linux-sound@vger.kernel.org
Cc: kernel-team@android.com
Reported-by: Betty Zhou <bettyzhou@google.com>
Suggested-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: John Stultz <jstultz@google.com>
Message-Id: <20250116194114.3375616-1-jstultz@google.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-02 07:50:54 +02:00
arch parisc: PDT: Fix missing prototype warning 2025-05-02 07:50:53 +02:00
block block: fix resource leak in blk_register_queue() error path 2025-04-25 10:45:42 +02:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2025-04-25 10:45:58 +02:00
crypto crypto: null - Use spin lock instead of mutex 2025-05-02 07:50:52 +02:00
Documentation sched/topology: Consolidate and clean up access to a CPU's max compute capacity 2025-05-02 07:50:41 +02:00
drivers usb: dwc3: gadget: Avoid using reserved endpoints on Intel Merrifield 2025-05-02 07:50:54 +02:00
fs fs/ntfs3: Fix WARNING in ntfs_extend_initialized_size 2025-05-02 07:50:54 +02:00
include sched/cpufreq: Rework schedutil governor performance estimation 2025-05-02 07:50:41 +02:00
init rust: Disallow BTF generation with Rust + LTO 2025-03-22 12:50:48 -07:00
io_uring io_uring: fix 'sync' handling of io_fallback_tw() 2025-05-02 07:50:47 +02:00
ipc ipc: fix memleak if msg_init_ns failed in create_ipc_ns 2024-12-09 10:32:54 +01:00
kernel bpf: Reject attaching fexit/fmod_ret to __noreturn functions 2025-05-02 07:50:53 +02:00
lib string: Add load_unaligned_zeropad() code path to sized_strscpy() 2025-04-25 10:45:50 +02:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm mm: fix apply_to_existing_page_range() 2025-04-25 10:45:48 +02:00
net net: selftests: initialize TCP header and skb payload with zero 2025-05-02 07:50:46 +02:00
rust rust: lockdep: Remove support for dynamically allocated LockClassKeys 2025-03-22 12:50:50 -07:00
samples tracing: Verify event formats that have "%*p.." 2025-05-02 07:50:37 +02:00
scripts sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2025-04-25 10:45:58 +02:00
security landlock: Add the errata interface 2025-04-25 10:45:57 +02:00
sound sound/virtio: Fix cancel_sync warnings on uninitialized work_structs 2025-05-02 07:50:54 +02:00
tools bpf: bpftool: Setting error code in do_loader() 2025-05-02 07:50:53 +02:00
usr kbuild: hdrcheck: fix cross build with clang 2025-03-13 12:58:38 +01:00
virt KVM: Use dedicated mutex to protect kvm_usage_count to avoid deadlock 2024-10-04 16:29:47 +02:00
.clang-format iommu: Add for_each_group_device() 2023-05-23 08:15:51 +02:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore Remove *.orig pattern from .gitignore 2024-10-04 16:29:44 +02:00
.mailmap 20 hotfixes. 12 are cc:stable and the remainder address post-6.5 issues 2023-10-24 09:52:16 -10:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING
CREDITS USB: Remove Wireless USB and UWB documentation 2023-08-09 14:17:32 +02:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig
MAINTAINERS sign-file,extract-cert: move common SSL helper functions to a header 2025-04-25 10:45:57 +02:00
Makefile Linux 6.6.88 2025-04-25 10:45:59 +02:00
README

Linux kernel
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There are several guides for kernel developers and users. These guides can
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There are various text files in the Documentation/ subdirectory,
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Please read the Documentation/process/changes.rst file, as it contains the
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