From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oa2-f0.google.com (mail-oa2-f0.google.com [74.125.231.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1E35446C856 for ; Tue, 25 Aug 2026 22:21:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.231.64 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787696491; cv=none; b=mknBveBidnH9Q/fkiwH37sYJMA9/g3mpXlk0Iw7BPszIn60O2ddmWYJulR7/2ajB1MY6WlO0Ekd5uMZ70fUtVthAXXgbT2XCAO7PqOxPQpDXHPcuVzqlx/mNwo9CauLCatBgZyvpNUqqRAY1rNeLHWYrGyzOY5/XAjHJofkN0VE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787696491; c=relaxed/simple; bh=NtMk5a35LHVxvfp1kxuAIL3ItbEFzZ90k2PmNlzzz8I=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=Gk2Jlt6EJNOhuLm5ZdKp23vxuAteBVetseyhvrfMBErXOXGuG50ql5/c1OQZWz07aAjc4uM50A1PMluG+WS8Xo8xHT1hCb7O3d5gsOT75XPj0Y77MfXRrORCgvI1FPStnLQSbJ9C2f7AvSFpYZnnXwn6xh0mnXkvRY8HVB3tMVc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=74.125.231.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-oa2-f0.google.com with SMTP id 586e51a60fabf-44cdbcd53b8so58500fac.0 for ; Tue, 25 Aug 2026 15:21:29 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1787696489; x=1788301289; h=content-type:to:from:subject:message-id:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=K/gHPJL2DlWvc+AZ1dm0BSlgYZtrrsxK/ph2MqO3QK4=; b=XJWzH8f/+XX8RJosXXa2q1wqN3XdYkEow9niR1b9j8Uo/FHrrWQcAx5HxqVAYncd03 pDK9TFgIL7MRFS2gBaKw2djCo4MDxJ5BqjlViw0Vu99Zc+1xFDNrBsXiOb2hNe4R9HdL Vc9JMHDwm5RP8jbHFXRIpOcQqHwYTpQK+FOIkb5AHZw1x9hOqNstgyB+opOImLbmrBUH onTggckn5Qz9J1Ulxf5DLa8jm3E0wp2PCAfeDXmYhR4/p7rLUz8JDpKgVlCByYWp5vqM F/vDxSCcCdnFYsE32QFMllYnrDn2vsuoS7TfFeOWGPZDv1xqUHsZSVkwuSpopmpu6ZoS Gw/g== X-Forwarded-Encrypted: i=1; AHgh+RoZwnEEM3oLM8bDqLPDsIOg8sJ6gZAknWoU8pizrGJuLIe45sz+zaTjKVE7CX+wzzs7aGlT+GnS9ufF0Ro=@vger.kernel.org X-Gm-Message-State: AFuF++kP9ZCNGeqbl1peIYOX+r2TbReXh9Bg3ntwOD1J++Bj+eF1k8Aw DywgXf9oP+Svd2758CCe6eTTsR6ZENiV8+HLggybDdROyk1o+rUnX7AjKZHWTQaelYG8GvSqEZx jcv2vRCQksh5MzNp42v65R1go7YYL2z8OT0HojfSn9lPXQR2dq/+s8DM9l1Y= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6808:5183:b0:497:df42:1dff with SMTP id 5614622812f47-4b3668b51cfmr3331541b6e.1.1787696488945; Tue, 25 Aug 2026 15:21:28 -0700 (PDT) Date: Tue, 25 Aug 2026 15:21:28 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a8e1568.a5a502ce.31d34.0073.GAE@google.com> Subject: [syzbot] [media?] WARNING in vidtv_start_feed From: syzbot To: dwlsalmeida@gmail.com, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, mchehab@kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 4e69c1856bfd Merge tag 'drm-next-2026-08-20' of https://gi.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=12a60625580000 kernel config: https://syzkaller.appspot.com/x/.config?x=6330e13b2e20bb12 dashboard link: https://syzkaller.appspot.com/bug?extid=525fda837bd5fc2be560 compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/f9abc0d6723c/disk-4e69c185.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/11f2728e2c65/vmlinux-4e69c185.xz kernel image: https://storage.googleapis.com/syzbot-assets/a175945b1e38/bzImage-4e69c185.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+525fda837bd5fc2be560@syzkaller.appspotmail.com ------------[ 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.0.342/7078 WARNING: kernel/locking/mutex.c:625 at __mutex_lock+0x12e6/0x1550 kernel/locking/mutex.c:821, CPU#1: syz.0.342/7078 Modules linked in: CPU: 1 UID: 0 PID: 7078 Comm: syz.0.342 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:625 [inline] RIP: 0010:__mutex_lock+0x12ed/0x1550 kernel/locking/mutex.c:821 Code: 29 79 90 48 c1 e8 03 0f b6 04 18 84 c0 0f 85 47 02 00 00 83 3d 77 a5 9a 04 00 75 13 48 8d 3d ba 9b 9d 04 48 c7 c6 80 fe 0c 8c <67> 48 0f b9 3a 90 e9 67 ee ff ff 90 0f 0b 90 e9 3a f2 ff ff 90 0f RSP: 0018:ffffc900051b7960 EFLAGS: 00010246 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000080000 RDX: ffffc9001174a000 RSI: ffffffff8c0cfe80 RDI: ffffffff907c1f80 RBP: ffffc900051b7af0 R08: ffffffff90792933 R09: 1ffffffff20f2526 R10: dffffc0000000000 R11: fffffbfff20f2527 R12: ffff888026075128 R13: 0000000000000000 R14: 1ffff92000a36f40 R15: 0000000000000000 FS: 00007fad388b86c0(0000) GS:ffff888124e0c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b33316ff8 CR3: 000000002e6c2000 CR4: 0000000000350ef0 Call Trace: vidtv_start_feed+0x102/0x5a0 drivers/media/test-drivers/vidtv/vidtv_bridge.c:233 dmx_ts_feed_start_filtering+0x129/0x220 drivers/media/dvb-core/dvb_demux.c:747 dvb_dmxdev_start_feed drivers/media/dvb-core/dmxdev.c:658 [inline] dvb_dmxdev_filter_start+0x434/0x10d0 drivers/media/dvb-core/dmxdev.c:769 dvb_demux_do_ioctl+0x48b/0x540 drivers/media/dvb-core/dmxdev.c:1099 dvb_usercopy+0x199/0x2e0 drivers/media/dvb-core/dvbdev.c:996 dvb_demux_ioctl+0x29/0x40 drivers/media/dvb-core/dmxdev.c:1208 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fad3799e0d9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fad388b8028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fad37c26180 RCX: 00007fad3799e0d9 RDX: 00002000000000c0 RSI: 0000000040146f2c RDI: 0000000000000003 RBP: 00007fad37a35024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fad37c26218 R14: 00007fad37c26180 R15: 00007fff575e5288 ---------------- Code disassembly (best guess): 0: 29 79 90 sub %edi,-0x70(%rcx) 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 77 a5 9a 04 00 cmpl $0x0,0x49aa577(%rip) # 0x49aa591 1a: 75 13 jne 0x2f 1c: 48 8d 3d ba 9b 9d 04 lea 0x49d9bba(%rip),%rdi # 0x49d9bdd 23: 48 c7 c6 80 fe 0c 8c mov $0xffffffff8c0cfe80,%rsi * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: 90 nop 30: e9 67 ee ff ff jmp 0xffffee9c 35: 90 nop 36: 0f 0b ud2 38: 90 nop 39: e9 3a f2 ff ff jmp 0xfffff278 3e: 90 nop 3f: 0f .byte 0xf --- 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