------------[ 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.2.169/6875
WARNING: kernel/locking/mutex.c:625 at __mutex_lock+0x944/0x1bc0 kernel/locking/mutex.c:821, CPU#1: syz.2.169/6875
Modules linked in:
CPU: 1 UID: 0 PID: 6875 Comm: syz.2.169 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:625 [inline]
RIP: 0010:__mutex_lock+0x94b/0x1bc0 kernel/locking/mutex.c:821
Code: 0f b6 14 11 38 d0 7c 08 84 d2 0f 85 b4 10 00 00 44 8b 05 b8 a2 7b 05 45 85 c0 75 13 48 8d 3d 9c a7 7e 05 48 c7 c6 40 d2 ef 8b <67> 48 0f b9 3a 90 e9 1b f8 ff ff 4d 8d a7 f0 0a 00 00 4c 89 e7 e8
RSP: 0000:ffffc90003b376a0 EFLAGS: 00010246
RAX: 0000000000000003 RBX: ffff88804bff6010 RCX: 1ffffffff22890ec
RDX: 0000000000000000 RSI: ffffffff8befd240 RDI: ffffffff91478c50
RBP: ffffc90003b37810 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: ffff88802614e320
FS:  0000000000000000(0000) GS:ffff888096a8f000(0063) knlGS:00000000f67eab40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00000000f67e9ff4 CR3: 000000004bbc3000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 as102_stream_ctrl+0x28/0xd0 drivers/media/usb/as102/as102_drv.c:259
 __dvb_frontend_open+0x122/0xf20 drivers/media/dvb-core/dvb_frontend.c:2772
 dvb_frontend_open+0x77c/0x910 drivers/media/dvb-core/dvb_frontend.c:2884
 dvb_device_open+0x270/0x3b0 drivers/media/dvb-core/dvbdev.c:109
 chrdev_open+0x234/0x6a0 fs/char_dev.c:411
 do_dentry_open+0x6ab/0x14d0 fs/open.c:996
 vfs_open+0x82/0x3f0 fs/open.c:1101
 do_open fs/namei.c:4837 [inline]
 path_openat+0x19fa/0x2440 fs/namei.c:5000
 do_file_open+0x20e/0x430 fs/namei.c:5029
 do_sys_openat2+0x10f/0x1e0 fs/open.c:1417
 do_sys_open fs/open.c:1423 [inline]
 __do_compat_sys_openat fs/open.c:1485 [inline]
 __se_compat_sys_openat fs/open.c:1483 [inline]
 __ia32_compat_sys_openat+0x12d/0x210 fs/open.c:1483
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:79 [inline]
 do_int80_emulation+0x166/0x650 arch/x86/entry/syscall_32.c:166
 asm_int80_emulation+0x1a/0x20 arch/x86/include/asm/idtentry.h:598
RIP: 0023:0xf71a74eb
Code: 57 56 53 8b 44 24 14 f6 00 08 75 23 8b 44 24 18 8b 5c 24 1c 8b 4c 24 20 8b 54 24 24 8b 74 24 28 8b 7c 24 2c 8b 6c 24 30 cd 80 <5b> 5e 5f 5d c3 5b 5e 5f 5d e9 f7 a1 ff ff 66 90 66 90 66 90 90 53
RSP: 002b:00000000f67ea03c EFLAGS: 00000246 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 00000000ffffff9c RCX: 00000000f67ea100
RDX: 0000000000000802 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess):
   0:	0f b6 14 11          	movzbl (%rcx,%rdx,1),%edx
   4:	38 d0                	cmp    %dl,%al
   6:	7c 08                	jl     0x10
   8:	84 d2                	test   %dl,%dl
   a:	0f 85 b4 10 00 00    	jne    0x10c4
  10:	44 8b 05 b8 a2 7b 05 	mov    0x57ba2b8(%rip),%r8d        # 0x57ba2cf
  17:	45 85 c0             	test   %r8d,%r8d
  1a:	75 13                	jne    0x2f
  1c:	48 8d 3d 9c a7 7e 05 	lea    0x57ea79c(%rip),%rdi        # 0x57ea7bf
  23:	48 c7 c6 40 d2 ef 8b 	mov    $0xffffffff8befd240,%rsi
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	90                   	nop
  30:	e9 1b f8 ff ff       	jmp    0xfffff850
  35:	4d 8d a7 f0 0a 00 00 	lea    0xaf0(%r15),%r12
  3c:	4c 89 e7             	mov    %r12,%rdi
  3f:	e8                   	.byte 0xe8