[syzbot] [media?] WARNING in vb2_start_streaming

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Aug 4, 2026, 10:05:25 PM (13 hours ago) Aug 4
to linux-...@vger.kernel.org, linux...@vger.kernel.org, m.szyp...@samsung.com, mch...@kernel.org, syzkall...@googlegroups.com, tf...@chromium.org
Hello,

syzbot found the following issue on:

HEAD commit: a2cf4ef33184 Merge tag 'devicetree-fixes-for-7.2' of git:/..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1397fa49580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f221a1b5d497ed15
dashboard link: https://syzkaller.appspot.com/bug?extid=930e6201080a31e9d0c8
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
userspace arch: i386

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-a2cf4ef3.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/c2efb8cc15c7/vmlinux-a2cf4ef3.xz
kernel image: https://storage.googleapis.com/syzbot-assets/2391dcb843b8/bzImage-a2cf4ef3.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+930e62...@syzkaller.appspotmail.com

------------[ cut here ]------------
!list_empty(&q->done_list)
WARNING: drivers/media/common/videobuf2/videobuf2-core.c:1821 at vb2_start_streaming+0x247/0x570 drivers/media/common/videobuf2/videobuf2-core.c:1821, CPU#2: syz.3.3964/23279
Modules linked in:
CPU: 2 UID: 0 PID: 23279 Comm: syz.3.3964 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:vb2_start_streaming+0x247/0x570 drivers/media/common/videobuf2/videobuf2-core.c:1821
Code: 00 00 00 00 fc ff df 4c 89 e2 48 c1 ea 03 80 3c 02 00 0f 85 b5 02 00 00 48 8b 83 68 01 00 00 49 39 c4 74 0d e8 9a 35 e2 f9 90 <0f> 0b 90 eb 02 31 ed e8 8d 35 e2 f9 89 e8 48 83 c4 30 5b 5d 41 5c
RSP: 0000:ffffc90002e4fa50 EFLAGS: 00010283
RAX: 00000000000027ef RBX: ffff88806deda770 RCX: ffffc90007779000
RDX: 0000000000080000 RSI: ffffffff88277866 RDI: ffff8880282c2540
RBP: 00000000ffffffed R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88806deda8d8
R13: 0000000000000000 R14: ffff88806deda7d0 R15: ffff88806deda7a0
FS: 0000000000000000(0000) GS:ffff888096de1000(0063) knlGS:00000000f547db40
CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00000000f6fff000 CR3: 00000000739b9000 CR4: 0000000000352ef0
Call Trace:
<TASK>
vb2_core_streamon+0x26a/0x3c0 drivers/media/common/videobuf2/videobuf2-core.c:2336
__vb2_init_fileio+0xcb7/0x1000 drivers/media/common/videobuf2/videobuf2-core.c:2949
__vb2_perform_fileio+0x9ba/0x1380 drivers/media/common/videobuf2/videobuf2-core.c:3025
vb2_fop_read+0x211/0x520 drivers/media/common/videobuf2/videobuf2-v4l2.c:1215
v4l2_read+0x229/0x2c0 drivers/media/v4l2-core/v4l2-dev.c:316
vfs_read+0x1e4/0xb40 fs/read_write.c:572
ksys_read+0x12a/0x250 fs/read_write.c:716
do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
__do_fast_syscall_32+0xe7/0x970 arch/x86/entry/syscall_32.c:307
do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:332
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf708efec
Code: Unable to access opcode bytes at 0xf708efc2.
RSP: 002b:00000000f547d50c EFLAGS: 00000292 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000080002c00
RDX: 0000000000002020 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>


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