------------[ 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.4.1367/11036
WARNING: kernel/locking/mutex.c:625 at __mutex_lock+0x944/0x1bc0 kernel/locking/mutex.c:821, CPU#1: syz.4.1367/11036
Modules linked in:
CPU: 1 UID: 0 PID: 11036 Comm: syz.4.1367 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:__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 9d 7d 05 45 85 c0 75 13 48 8d 3d 9c a2 80 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: 0018:ffffc9000d0ff950 EFLAGS: 00010246
RAX: 0000000000000003 RBX: ffff888000181128 RCX: 1ffffffff228764c
RDX: 0000000000000000 RSI: ffffffff8befd240 RDI: ffffffff9146b750
RBP: ffffc9000d0ffac0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000200000000
FS:  0000000000000000(0000) GS:ffff888096aa9000(0063) knlGS:00000000f5454b40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000000000c3d852b CR3: 000000004e7e0000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 vidtv_start_feed+0x109/0x500 drivers/media/test-drivers/vidtv/vidtv_bridge.c:233
 dmx_ts_feed_start_filtering+0xf6/0x220 drivers/media/dvb-core/dvb_demux.c:747
 dvb_dmxdev_start_feed+0x273/0x3f0 drivers/media/dvb-core/dmxdev.c:658
 dvb_dmxdev_filter_start+0x1b6/0xdd0 drivers/media/dvb-core/dmxdev.c:769
 dvb_dmxdev_pes_filter_set drivers/media/dvb-core/dmxdev.c:985 [inline]
 dvb_demux_do_ioctl+0xe64/0x1200 drivers/media/dvb-core/dmxdev.c:1099
 dvb_usercopy+0x167/0x340 drivers/media/dvb-core/dvbdev.c:996
 dvb_demux_ioctl+0x29/0x40 drivers/media/dvb-core/dmxdev.c:1208
 __do_compat_sys_ioctl fs/ioctl.c:695 [inline]
 __se_compat_sys_ioctl fs/ioctl.c:638 [inline]
 __ia32_compat_sys_ioctl+0x2cf/0x360 fs/ioctl.c:638
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:79 [inline]
 __do_fast_syscall_32+0x13a/0x8b0 arch/x86/entry/syscall_32.c:291
 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:316
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7fd7fec
Code: Unable to access opcode bytes at 0xf7fd7fc2.
RSP: 002b:00000000f545450c EFLAGS: 00000292 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000040146f2c
RDX: 00000000800000c0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000292 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 9d 7d 05 	mov    0x57d9db8(%rip),%r8d        # 0x57d9dcf
  17:	45 85 c0             	test   %r8d,%r8d
  1a:	75 13                	jne    0x2f
  1c:	48 8d 3d 9c a2 80 05 	lea    0x580a29c(%rip),%rdi        # 0x580a2bf
  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