Re: [syzbot] [media?] WARNING in as102_stream_ctrl

syzbot has found a reproducer for the following issue on:

HEAD commit:    3d08ff75a47a Add linux-next specific files for 20260810
git tree:       linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=11fdca9e580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=5ba0556605934602
dashboard link: https://syzkaller.appspot.com/bug?extid=ea047a32630b1f47da67
compiler:       Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=13b01079580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/227afac921c2/disk-3d08ff75.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/236f7cfe0ac3/vmlinux-3d08ff75.xz
kernel image: https://storage.googleapis.com/syzbot-assets/aea89831fd96/bzImage-3d08ff75.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email protected]

------------[ cut here ]------------
DEBUG_LOCKS_WARN_ON(lock->magic != lock)
WARNING: kernel/locking/mutex.c:625 at __mutex_lock_common kernel/locking/mutex.c:625 [inline], CPU#1: syz.3.80/6275
WARNING: kernel/locking/mutex.c:625 at __mutex_lock+0x12d8/0x1550 kernel/locking/mutex.c:821, CPU#1: syz.3.80/6275
Modules linked in:
CPU: 1 UID: 0 PID: 6275 Comm: syz.3.80 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:625 [inline]
RIP: 0010:__mutex_lock+0x12df/0x1550 kernel/locking/mutex.c:821
Code: 2e 59 90 48 c1 e8 03 0f b6 04 18 84 c0 0f 85 47 02 00 00 83 3d 05 ad 7c 04 00 75 13 48 8d 3d 18 a8 7f 04 48 c7 c6 e0 11 ed 8b <67> 48 0f b9 3a 90 e9 75 ee ff ff 90 0f 0b 90 e9 48 f2 ff ff 90 0f
RSP: 0018:ffffc90003e5f680 EFLAGS: 00010246
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffff88807f5d1f40
RDX: 0000000000000000 RSI: ffffffff8bed11e0 RDI: ffffffff905c29a0
RBP: ffffc90003e5f820 R08: ffffffff90592e83 R09: 1ffffffff20b25d0
R10: dffffc0000000000 R11: fffffbfff20b25d1 R12: ffff888078e08010
R13: 0000000000000000 R14: 1ffff920007cbee4 R15: 0000000000000000
FS:  000055556341e500(0000) GS:ffff88812500d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc7f45eb7c0 CR3: 00000000324b2000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 as102_stream_ctrl+0x27/0xc0 drivers/media/usb/as102/as102_drv.c:259
 __dvb_frontend_open+0x2e9/0xc40 drivers/media/dvb-core/dvb_frontend.c:2772
 dvb_device_open+0x24f/0x340 drivers/media/dvb-core/dvbdev.c:109
 chrdev_open+0x4d9/0x600 fs/char_dev.c:411
 do_dentry_open+0x816/0x1380 fs/open.c:996
 vfs_open+0x3b/0x340 fs/open.c:1101
 do_open fs/namei.c:4837 [inline]
 path_openat+0x1443/0x1d60 fs/namei.c:5000
 do_file_open+0x23e/0x4a0 fs/namei.c:5029
 do_sys_openat2+0x115/0x200 fs/open.c:1417
 do_sys_open fs/open.c:1423 [inline]
 __do_sys_openat fs/open.c:1439 [inline]
 __se_sys_openat fs/open.c:1434 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1434
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x510 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbe1bf5e90e
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007ffd8f0c6fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 000055556341e500 RCX: 00007fbe1bf5e90e
RDX: 0000000000000802 RSI: 00007ffd8f0c70c0 RDI: ffffffffffffff9c
RBP: 00007ffd8f0c70c0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007fbe1c225fac R14: 00007fbe1c225fa0 R15: 00007fbe1c225fa0
 </TASK>
----------------
Code disassembly (best guess):
   0:	2e 59                	cs pop %rcx
   2:	90                   	nop
   3:	48 c1 e8 03          	shr    $0x3,%rax
   7:	0f b6 04 18          	movzbl (%rax,%rbx,1),%eax
   b:	84 c0                	test   %al,%al
   d:	0f 85 47 02 00 00    	jne    0x25a
  13:	83 3d 05 ad 7c 04 00 	cmpl   $0x0,0x47cad05(%rip)        # 0x47cad1f
  1a:	75 13                	jne    0x2f
  1c:	48 8d 3d 18 a8 7f 04 	lea    0x47fa818(%rip),%rdi        # 0x47fa83b
  23:	48 c7 c6 e0 11 ed 8b 	mov    $0xffffffff8bed11e0,%rsi
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	90                   	nop
  30:	e9 75 ee ff ff       	jmp    0xffffeeaa
  35:	90                   	nop
  36:	0f 0b                	ud2
  38:	90                   	nop
  39:	e9 48 f2 ff ff       	jmp    0xfffff286
  3e:	90                   	nop
  3f:	0f                   	.byte 0xf


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