Linux Media Controller development
 help / color / mirror / Atom feed
From: syzbot <syzbot+477f9c41b0a7d90fb9cc@syzkaller.appspotmail.com>
To: linux-kernel@vger.kernel.org, linux-media@vger.kernel.org,
	 mchehab@kernel.org, syzkaller-bugs@googlegroups.com
Subject: [syzbot] [media?] WARNING in vp702x_read_mac_addr
Date: Fri, 21 Aug 2026 00:41:34 -0700	[thread overview]
Message-ID: <6a88012e.dbb3a75c.13dd47.0008.GAE@google.com> (raw)

Hello,

syzbot found the following issue on:

HEAD commit:    dcb68831eac7 Merge tag 'block-7.2-20260815' of git://git.k..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15a4d949580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=65bd434865e8f85c
dashboard link: https://syzkaller.appspot.com/bug?extid=477f9c41b0a7d90fb9cc
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-dcb68831.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/2788b4793ff6/vmlinux-dcb68831.xz
kernel image: https://storage.googleapis.com/syzbot-assets/28c6c79990ac/bzImage-dcb68831.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+477f9c41b0a7d90fb9cc@syzkaller.appspotmail.com

dvbdev: DVB: registering new adapter (TwinhanDTV StarBox DVB-S USB2.0 (VP7021))
usb 6-1: media controller created
------------[ 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: kworker/1:2/1349
WARNING: kernel/locking/mutex.c:625 at __mutex_lock+0x947/0x1bd0 kernel/locking/mutex.c:821, CPU#1: kworker/1:2/1349
Modules linked in:
CPU: 1 UID: 0 PID: 1349 Comm: kworker/1:2 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
Workqueue: usb_hub_wq hub_event
RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:625 [inline]
RIP: 0010:__mutex_lock+0x94e/0x1bd0 kernel/locking/mutex.c:821
Code: 0f b6 14 11 38 d0 7c 08 84 d2 0f 85 c6 10 00 00 44 8b 35 45 a7 66 05 45 85 f6 75 13 48 8d 3d 19 05 6a 05 48 c7 c6 a0 c8 cf 8b <67> 48 0f b9 3a 90 e9 18 f8 ff ff 4d 8d a7 e8 0a 00 00 4c 89 e7 e8
RSP: 0018:ffffc90006ebec80 EFLAGS: 00010246
RAX: 0000000000000003 RBX: ffff8880253fe100 RCX: 1ffffffff2244970
RDX: 0000000000000000 RSI: ffffffff8bcfc8a0 RDI: ffffffff9125a960
RBP: ffffc90006ebedf0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888096ce7000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f74382f0 CR3: 000000002a209000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 vp702x_read_mac_addr+0x51/0x130 drivers/media/usb/dvb-usb/vp702x.c:297
 dvb_usb_adapter_dvb_init+0x2dd/0x860 drivers/media/usb/dvb-usb/dvb-usb-dvb.c:165
 dvb_usb_adapter_init drivers/media/usb/dvb-usb/dvb-usb-init.c:86 [inline]
 dvb_usb_init drivers/media/usb/dvb-usb/dvb-usb-init.c:186 [inline]
 dvb_usb_device_init.cold+0xbd5/0x14bb drivers/media/usb/dvb-usb/dvb-usb-init.c:310
 vp702x_usb_probe+0x8d/0x210 drivers/media/usb/dvb-usb/vp702x.c:342
 usb_probe_interface+0x303/0x8f0 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:628 [inline]
 really_probe+0x241/0xa60 drivers/base/dd.c:706
 __driver_probe_device+0x20e/0x450 drivers/base/dd.c:868
 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
 bus_probe_device+0x64/0x160 drivers/base/bus.c:620
 device_add+0x121d/0x1970 drivers/base/core.c:3772
 usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2268
 usb_generic_driver_probe+0xa1/0xe0 drivers/usb/core/generic.c:250
 usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291
 call_driver_probe drivers/base/dd.c:628 [inline]
 really_probe+0x241/0xa60 drivers/base/dd.c:706
 __driver_probe_device+0x20e/0x450 drivers/base/dd.c:868
 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
 bus_probe_device+0x64/0x160 drivers/base/bus.c:620
 device_add+0x121d/0x1970 drivers/base/core.c:3772
 usb_new_device.part.0+0xcc2/0x1686 drivers/usb/core/hub.c:2703
 usb_new_device include/linux/workqueue.h:714 [inline]
 hub_port_connect drivers/usb/core/hub.c:5575 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5715 [inline]
 port_event drivers/usb/core/hub.c:5879 [inline]
 hub_event.cold+0x1e3/0xe90 drivers/usb/core/hub.c:5961
 process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
 process_scheduled_works kernel/workqueue.c:3405 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </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 c6 10 00 00    	jne    0x10d6
  10:	44 8b 35 45 a7 66 05 	mov    0x566a745(%rip),%r14d        # 0x566a75c
  17:	45 85 f6             	test   %r14d,%r14d
  1a:	75 13                	jne    0x2f
  1c:	48 8d 3d 19 05 6a 05 	lea    0x56a0519(%rip),%rdi        # 0x56a053c
  23:	48 c7 c6 a0 c8 cf 8b 	mov    $0xffffffff8bcfc8a0,%rsi
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	90                   	nop
  30:	e9 18 f8 ff ff       	jmp    0xfffff84d
  35:	4d 8d a7 e8 0a 00 00 	lea    0xae8(%r15),%r12
  3c:	4c 89 e7             	mov    %r12,%rdi
  3f:	e8                   	.byte 0xe8


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

                 reply	other threads:[~2026-08-21  7:41 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=6a88012e.dbb3a75c.13dd47.0008.GAE@google.com \
    --to=syzbot+477f9c41b0a7d90fb9cc@syzkaller.appspotmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-media@vger.kernel.org \
    --cc=mchehab@kernel.org \
    --cc=syzkaller-bugs@googlegroups.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox