[syzbot] [media?] INFO: trying to register non-static key in __vb2_queue_cancel

[syzbot] [media?] INFO: trying to register non-static key in __vb2_queue_cancel

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    cc2b5f627e8c Add linux-next specific files for 20260714
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=17fb04b9580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=2290ccbf984c524f
dashboard link: https://syzkaller.appspot.com/bug?extid=2302c5dc59995fbb8089
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=12d598b9580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=14500789580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/6836f8efb1da/disk-cc2b5f62.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0109d3477cc7/vmlinux-cc2b5f62.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c2e49e350bbf/bzImage-cc2b5f62.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2302c5dc59995fbb8089@syzkaller.appspotmail.com

em28xx 1-1:0.132: AC97 chip type couldn't be determined
em28xx 1-1:0.132: No AC97 audio processor
usb 1-1: Decoder not found
em28xx 1-1:0.132: failed to create media graph
em28xx 1-1:0.132: V4L2 device video103 deregistered
INFO: trying to register non-static key.
The code is fine but needs lockdep annotation, or maybe
you didn't initialize this object before use?
turning off the locking correctness validator.
CPU: 1 UID: 0 PID: 5649 Comm: kworker/1:3 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026
Workqueue: events request_module_async
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 assign_lock_key+0x133/0x150 kernel/locking/lockdep.c:1000
 register_lock_class+0xcc/0x2e0 kernel/locking/lockdep.c:1315
 __lock_acquire+0xaf/0x2e40 kernel/locking/lockdep.c:5128
 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5906
 rt_spin_lock+0x83/0x400 kernel/locking/spinlock_rt.c:56
 spin_lock include/linux/spinlock_rt.h:45 [inline]
 __wake_up_common_lock+0x2f/0x1f0 kernel/sched/wait.c:124
 __vb2_queue_cancel+0x2de/0xdc0 drivers/media/common/videobuf2/videobuf2-core.c:2244
 vb2_core_queue_release+0x2f/0x150 drivers/media/common/videobuf2/videobuf2-core.c:2677
 vb2_queue_release drivers/media/common/videobuf2/videobuf2-v4l2.c:956 [inline]
 vb2_video_unregister_device+0x15b/0x200 drivers/media/common/videobuf2/videobuf2-v4l2.c:1292
 em28xx_v4l2_init+0x1c60/0x3140 drivers/media/usb/em28xx/em28xx-video.c:3097
 em28xx_init_extension+0x120/0x1d0 drivers/media/usb/em28xx/em28xx-core.c:1248
 process_one_work+0xaaf/0x1480 kernel/workqueue.c:3379
 process_scheduled_works kernel/workqueue.c:3462 [inline]
 worker_thread+0xb05/0x10d0 kernel/workqueue.c:3543
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 UID: 0 PID: 5649 Comm: kworker/1:3 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026
Workqueue: events request_module_async
RIP: 0010:__wake_up_common kernel/sched/wait.c:104 [inline]
RIP: 0010:__wake_up_common_lock+0xd6/0x1f0 kernel/sched/wait.c:125
Code: 0f 84 d4 00 00 00 44 8b 7c 24 04 eb 13 48 ba 00 00 00 00 00 fc ff df 4c 39 ed 0f 84 ba 00 00 00 49 89 ee 48 89 e8 48 c1 e8 03 <80> 3c 10 00 74 12 4c 89 f7 e8 1c ce 93 00 48 ba 00 00 00 00 00 fc
RSP: 0018:ffffc9000595f908 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: ffffffff8bcbd060 RDI: 00000000ffffffff
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1fa1890 R12: ffff88803e181b14
R13: ffff88803e181c28 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888125af2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005625301fb660 CR3: 000000003774e000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 __vb2_queue_cancel+0x2de/0xdc0 drivers/media/common/videobuf2/videobuf2-core.c:2244
 vb2_core_queue_release+0x2f/0x150 drivers/media/common/videobuf2/videobuf2-core.c:2677
 vb2_queue_release drivers/media/common/videobuf2/videobuf2-v4l2.c:956 [inline]
 vb2_video_unregister_device+0x15b/0x200 drivers/media/common/videobuf2/videobuf2-v4l2.c:1292
 em28xx_v4l2_init+0x1c60/0x3140 drivers/media/usb/em28xx/em28xx-video.c:3097
 em28xx_init_extension+0x120/0x1d0 drivers/media/usb/em28xx/em28xx-core.c:1248
 process_one_work+0xaaf/0x1480 kernel/workqueue.c:3379
 process_scheduled_works kernel/workqueue.c:3462 [inline]
 worker_thread+0xb05/0x10d0 kernel/workqueue.c:3543
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__wake_up_common kernel/sched/wait.c:104 [inline]
RIP: 0010:__wake_up_common_lock+0xd6/0x1f0 kernel/sched/wait.c:125
Code: 0f 84 d4 00 00 00 44 8b 7c 24 04 eb 13 48 ba 00 00 00 00 00 fc ff df 4c 39 ed 0f 84 ba 00 00 00 49 89 ee 48 89 e8 48 c1 e8 03 <80> 3c 10 00 74 12 4c 89 f7 e8 1c ce 93 00 48 ba 00 00 00 00 00 fc
RSP: 0018:ffffc9000595f908 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: ffffffff8bcbd060 RDI: 00000000ffffffff
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1fa1890 R12: ffff88803e181b14
R13: ffff88803e181c28 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888125af2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005625301fb660 CR3: 000000003774e000 CR4: 00000000003526f0
----------------
Code disassembly (best guess):
   0:	0f 84 d4 00 00 00    	je     0xda
   6:	44 8b 7c 24 04       	mov    0x4(%rsp),%r15d
   b:	eb 13                	jmp    0x20
   d:	48 ba 00 00 00 00 00 	movabs $0xdffffc0000000000,%rdx
  14:	fc ff df
  17:	4c 39 ed             	cmp    %r13,%rbp
  1a:	0f 84 ba 00 00 00    	je     0xda
  20:	49 89 ee             	mov    %rbp,%r14
  23:	48 89 e8             	mov    %rbp,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	80 3c 10 00          	cmpb   $0x0,(%rax,%rdx,1) <-- trapping instruction
  2e:	74 12                	je     0x42
  30:	4c 89 f7             	mov    %r14,%rdi
  33:	e8 1c ce 93 00       	call   0x93ce54
  38:	48                   	rex.W
  39:	ba 00 00 00 00       	mov    $0x0,%edx
  3e:	00 fc                	add    %bh,%ah


---
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 syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

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

Re: [syzbot] [media?] INFO: trying to register non-static key in __vb2_queue_cancel

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
lost connection to test machine



Tested on:

commit:         cc2b5f62 Add linux-next specific files for 20260714
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
console output: https://syzkaller.appspot.com/x/log.txt?x=117a58b9580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=2290ccbf984c524f
dashboard link: https://syzkaller.appspot.com/bug?extid=2302c5dc59995fbb8089
compiler:       Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
patch:          https://syzkaller.appspot.com/x/patch.diff?x=167ff346580000

Re: [syzbot] [media?] INFO: trying to register non-static key in __vb2_queue_cancel

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
lost connection to test machine



Tested on:

commit:         cc2b5f62 Add linux-next specific files for 20260714
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
console output: https://syzkaller.appspot.com/x/log.txt?x=11d20b46580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=2290ccbf984c524f
dashboard link: https://syzkaller.appspot.com/bug?extid=2302c5dc59995fbb8089
compiler:       Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
patch:          https://syzkaller.appspot.com/x/patch.diff?x=17d658b9580000

Re: [syzbot] [media?] INFO: trying to register non-static key in __vb2_queue_cancel

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
lost connection to test machine



Tested on:

commit:         cc2b5f62 Add linux-next specific files for 20260714
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=10b844b9580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=2290ccbf984c524f
dashboard link: https://syzkaller.appspot.com/bug?extid=2302c5dc59995fbb8089
compiler:       Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8

Note: no patches were applied.

Re: [syzbot] [media?] INFO: trying to register non-static key in __vb2_queue_cancel

[syzbot]

> #syz test https://

I've failed to parse your command.
Did you perhaps forget to provide the branch name, or added an extra ':'?
Please use one of the two supported formats:
1. #syz test
2. #syz test: repo branch-or-commit-hash
Note the lack of ':' in option 1.

> git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
> cc2b5f627e8ccbae1188ef2d8be3e451d7f933a5

Re: [syzbot] [media?] INFO: trying to register non-static key in __vb2_queue_cancel

[syzbot]

> #syz test: https://

"https://" does not look like a valid git repo address.

> git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
> cc2b5f627e8ccbae1188ef2d8be3e451d7f933a5
>
> On Wed, Jul 15, 2026 at 8:37 PM syzbot <
> syzbot+2302c5dc59995fbb8089@syzkaller.appspotmail.com> wrote:
>
>> > #syz test https://
>>
>> I've failed to parse your command.
>> Did you perhaps forget to provide the branch name, or added an extra ':'?
>> Please use one of the two supported formats:
>> 1. #syz test
>> 2. #syz test: repo branch-or-commit-hash
>> Note the lack of ':' in option 1.
>>
>> > git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
>> > cc2b5f627e8ccbae1188ef2d8be3e451d7f933a5
>>

Re: [syzbot] [media?] INFO: trying to register non-static key in __vb2_queue_cancel

[syzbot]

> #syz test git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git

I've failed to parse your command.
Did you perhaps forget to provide the branch name, or added an extra ':'?
Please use one of the two supported formats:
1. #syz test
2. #syz test: repo branch-or-commit-hash
Note the lack of ':' in option 1.

> cc2b5f627e8ccbae1188ef2d8be3e451d7f933a5

Re: [syzbot] [media?] INFO: trying to register non-static key in __vb2_queue_cancel

[syzbot]

> #syz test: https://

"https://" does not look like a valid git repo address.

> git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
> cc2b5f627e8ccbae1188ef2d8be3e451d7f933a5

Re: [syzbot] [media?] INFO: trying to register non-static key in __vb2_queue_cancel

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
lost connection to test machine



Tested on:

commit:         cc2b5f62 Add linux-next specific files for 20260714
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
console output: https://syzkaller.appspot.com/x/log.txt?x=17858c32580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=2290ccbf984c524f
dashboard link: https://syzkaller.appspot.com/bug?extid=2302c5dc59995fbb8089
compiler:       Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8

Note: no patches were applied.

Re: [syzbot] [media?] INFO: trying to register non-static key in __vb2_queue_cancel

[Gautam Bhadoria]

 The syzbot test request is failing with "lost connection to test
machine" even when sending #syz test without any patch. This appears
to be unrelated to the proposed fix and may indicate a problem with
the current syzbot test environment.

Re: [syzbot] [media?] INFO: trying to register non-static key in __vb2_queue_cancel

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

928][    T1] pci_bus 0000:00: resource 7 [io  0xa000-0xbfff window]
[    5.040994][    T1] pci_bus 0000:00: resource 8 [mem 0x000a0000-0x000bffff window]
[    5.041069][    T1] pci_bus 0000:00: resource 9 [mem 0xc0000000-0xfebfefff window]
[    5.056552][    T1] pci 0000:00:00.0: Limiting direct PCI/PCI transfers
[    5.057829][    T1] PCI: CLS 0 bytes, default 64
[    5.062697][    T1] PCI-DMA: Using software bounce buffering for IO (SWIOTLB)
[    5.062755][    T1] software IO TLB: mapped [mem 0x00000000b4600000-0x00000000b8600000] (64MB)
[    5.091103][    T1] ACPI: bus type thunderbolt registered
[    5.110651][   T70] kworker/u8:4 (70) used greatest stack depth: 26408 bytes left
[    5.125500][    T1] RAPL PMU: API unit is 2^-32 Joules, 0 fixed counters, 10737418240 ms ovfl timer
[    5.169904][    T1] kvm_amd: CPU 0 isn't AMD or Hygon
[    5.169939][    T1] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x1fb63109b96, max_idle_ns: 440795265316 ns
[    5.177074][    T1] clocksource: Switched to clocksource tsc
[    5.256175][    T1] Initialise system trusted keyrings
[    5.264090][    T1] workingset: timestamp_bits=40 (anon: 35) max_order=21 bucket_order=0 (anon: 0)
[    5.282669][    T1] DLM installed
[    5.293488][    T1] squashfs: version 4.0 (2009/01/31) Phillip Lougher
[    5.312965][    T1] NFS: Registering the id_resolver key type
[    5.313172][    T1] Key type id_resolver registered
[    5.313186][    T1] Key type id_legacy registered
[    5.313573][    T1] nfs4filelayout_init: NFSv4 File Layout Driver Registering...
[    5.313793][    T1] nfs4flexfilelayout_init: NFSv4 Flexfile Layout Driver Registering...
[    5.334869][    T1] smbdirect: subsystem loading...
[    5.353534][    T1] smbdirect: subsystem loaded
[    5.378220][    T1] Key type cifs.spnego registered
[    5.378646][    T1] Key type cifs.idmap registered
[    5.388711][    T1] ntfs3: Enabled Linux POSIX ACLs support
[    5.388725][    T1] ntfs3: Read-only LZX/Xpress compression included
[    5.389252][    T1] jffs2: version 2.2. (NAND) (SUMMARY)  © 2001-2006 Red Hat, Inc.
[    5.401586][    T1] romfs: ROMFS MTD (C) 2007 Red Hat, Inc.
[    5.401943][    T1] QNX4 filesystem 0.2.3 registered.
[    5.402089][    T1] qnx6: QNX6 filesystem 1.0.0 registered.
[    5.403903][    T1] fuse: init (API version 7.45)
[    5.408825][    T1] orangefs_debugfs_init: called with debug mask: :none: :0:
[    5.424152][    T1] orangefs_init: module version upstream loaded
[    5.425732][    T1] JFS: nTxBlock = 8192, nTxLock = 65536
[    5.452094][    T1] SGI XFS with ACLs, security attributes, realtime, scrub, repair, quota, no debug enabled
[    5.482169][    T1] 9p: Installing v9fs 9p2000 file system support
[    5.483755][    T1] NILFS version 2 loaded
[    5.483769][    T1] befs: version: 0.9.3
[    5.485358][    T1] ocfs2: Registered cluster interface o2cb
[    5.486741][    T1] ocfs2: Registered cluster interface user
[    5.489406][    T1] OCFS2 User DLM kernel interface loaded
[    5.542362][    T1] gfs2: GFS2 installed
[    5.567883][    T1] ceph: loaded (mds proto 32)
[    5.586370][    T1] NET: Registered PF_ALG protocol family
[    5.587688][    T1] async_tx: api initialized (async)
[    5.587756][    T1] Key type asymmetric registered
[    5.587848][    T1] Asymmetric key parser 'x509' registered
[    5.587866][    T1] Asymmetric key parser 'pkcs8' registered
[    5.587883][    T1] Key type pkcs7_test registered
[    5.589016][    T1] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 239)
[    5.603067][    T1] io scheduler mq-deadline registered
[    5.603139][    T1] io scheduler kyber registered
[    5.604834][    T1] io scheduler bfq registered
[    5.649355][    T1] input: Power Button as /devices/platform/LNXPWRBN:00/input/input0
[    5.662681][    T1] ACPI: button: Power Button [PWRF]
[    5.667457][    T1] input: Sleep Button as /devices/platform/LNXSLPBN:00/input/input1
[    5.681011][    T1] ACPI: button: Sleep Button [SLPF]
[    5.718524][    T1] ioatdma: Intel(R) QuickData Technology Driver 5.00
[    5.772183][   T10] ACPI: \_SB_.LNKC: Enabled at IRQ 11
[    5.774597][   T10] virtio-pci 0000:00:03.0: virtio_pci: leaving for legacy driver
[    5.821763][   T10] ACPI: \_SB_.LNKD: Enabled at IRQ 10
[    5.821966][   T10] virtio-pci 0000:00:04.0: virtio_pci: leaving for legacy driver
[    5.872047][   T10] ACPI: \_SB_.LNKB: Enabled at IRQ 10
[    5.872225][   T10] virtio-pci 0000:00:06.0: virtio_pci: leaving for legacy driver
[    5.908391][   T10] virtio-pci 0000:00:07.0: virtio_pci: leaving for legacy driver
[    6.978343][    T1] N_HDLC line discipline registered with maxframe=4096
[    6.984196][    T1] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
[    7.005107][    T1] 00:02: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
[    7.038077][    T1] 00:03: ttyS1 at I/O 0x2f8 (irq = 3, base_baud = 115200) is a 16550A
[    7.067193][    T1] 00:04: ttyS2 at I/O 0x3e8 (irq = 6, base_baud = 115200) is a 16550A
[    7.095230][    T1] 00:05: ttyS3 at I/O 0x2e8 (irq = 7, base_baud = 115200) is a 16550A
[    7.150291][    T1] Non-volatile memory driver v1.3
[    7.194453][    T1] usbcore: registered new interface driver xillyusb
[    7.207219][    T1] ACPI: bus type drm_connector registered
[    7.219124][    T1] [drm] Initialized vgem 1.0.0 for vgem on minor 0
[    7.230757][    T1] ------------[ cut here ]------------
[    7.230772][    T1] [PLANE:35:plane-0] pixel format with alpha exposed but blend mode not setup
[    7.230797][    T1] WARNING: drivers/gpu/drm/drm_mode_config.c:873 at drm_mode_config_validate+0x1c6d/0x1e60, CPU#1: swapper/0/1
[    7.230848][    T1] Modules linked in:
[    7.230896][    T1] CPU: 1 UID: 0 PID: 1 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
[    7.230921][    T1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026
[    7.230941][    T1] RIP: 0010:drm_mode_config_validate+0x1cae/0x1e60
[    7.230980][    T1] Code: 0f 85 ae 00 00 00 4d 8d 77 10 8b 6d 00 4c 89 f0 48 c1 e8 03 80 3c 18 00 74 08 4c 89 f7 e8 6a 80 ae fc 49 8b 16 4c 89 ef 89 ee <67> 48 0f b9 3a eb 05 e8 a6 39 42 fc 49 bd 00 00 00 00 00 fc ff df
[    7.231012][    T1] RSP: 0000:ffffc90000067810 EFLAGS: 00010246
[    7.231030][    T1] RAX: 1ffff11004e4a808 RBX: dffffc0000000000 RCX: ffff88801d6eddc0
[    7.231047][    T1] RDX: ffff888026f1ab80 RSI: 0000000000000023 RDI: ffffffff8fdc0940
[    7.231063][    T1] RBP: 0000000000000023 R08: 0000000000000000 R09: 0000000000000000
[    7.231077][    T1] R10: dffffc0000000000 R11: fffffbfff1fa18f0 R12: dffffc0000000000
[    7.231093][    T1] R13: ffffffff8fdc0940 R14: ffff888027254040 R15: ffff888027254030
[    7.231110][    T1] FS:  0000000000000000(0000) GS:ffff888125af2000(0000) knlGS:0000000000000000
[    7.231129][    T1] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    7.231144][    T1] CR2: 0000000000000000 CR3: 000000000e1b0000 CR4: 00000000003526f0
[    7.231162][    T1] Call Trace:
[    7.231170][    T1]  <TASK>
[    7.231194][    T1]  ? debugfs_create_file_full+0x3f/0x60
[    7.231231][    T1]  drm_dev_register+0x7f/0xd80
[    7.231266][    T1]  vkms_create+0x40d/0x4f0
[    7.231292][    T1]  ? __pfx_vkms_init+0x10/0x10
[    7.231315][    T1]  vkms_init+0x57/0x80
[    7.231337][    T1]  do_one_initcall+0x250/0x870
[    7.231366][    T1]  ? __pfx_vkms_init+0x10/0x10
[    7.231389][    T1]  ? __pfx_do_one_initcall+0x10/0x10
[    7.231422][    T1]  ? clockevents_program_event+0x491/0x630
[    7.231451][    T1]  ? __pfx___schedule+0x10/0x10
[    7.231514][    T1]  ? irqentry_exit+0x218/0x8f0
[    7.231538][    T1]  ? lockdep_hardirqs_on+0x7a/0x110
[    7.231561][    T1]  ? irqentry_exit+0x218/0x8f0
[    7.231602][    T1]  ? strlen+0x35/0x70
[    7.231627][    T1]  ? next_arg+0x4a0/0x5e0
[    7.231654][    T1]  ? parameq+0x14d/0x170
[    7.231690][    T1]  ? parse_args+0x9c3/0xad0
[    7.231737][    T1]  ? trace_kmalloc+0x2a/0xf0
[    7.231771][    T1]  ? rcu_is_watching+0x15/0xb0
[    7.231820][    T1]  do_initcall_level+0x10a/0x1a0
[    7.231852][    T1]  ? kernel_init+0x22/0x1d0
[    7.231880][    T1]  do_initcalls+0x59/0xa0
[    7.231912][    T1]  kernel_init_freeable+0x29d/0x3e0
[    7.231941][    T1]  ? __pfx_kernel_init+0x10/0x10
[    7.231970][    T1]  kernel_init+0x22/0x1d0
[    7.232006][    T1]  ? __pfx_kernel_init+0x10/0x10
[    7.232033][    T1]  ret_from_fork+0x514/0xb70
[    7.232066][    T1]  ? __pfx_ret_from_fork+0x10/0x10
[    7.232098][    T1]  ? __switch_to+0xc89/0x1420
[    7.232127][    T1]  ? __pfx_kernel_init+0x10/0x10
[    7.232157][    T1]  ret_from_fork_asm+0x1a/0x30
[    7.232203][    T1]  </TASK>
[    7.232214][    T1] Kernel panic - not syncing: kernel: panic_on_warn set ...
[    7.232230][    T1] CPU: 1 UID: 0 PID: 1 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
[    7.232254][    T1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026
[    7.232266][    T1] Call Trace:
[    7.232274][    T1]  <TASK>
[    7.232283][    T1]  vpanic+0x56c/0xa60
[    7.232305][    T1]  ? __pfx__printk+0x10/0x10
[    7.232330][    T1]  ? __pfx_vpanic+0x10/0x10
[    7.232349][    T1]  ? is_bpf_text_address+0x292/0x2b0
[    7.232374][    T1]  ? is_bpf_text_address+0x26/0x2b0
[    7.232407][    T1]  panic+0xc5/0xd0
[    7.232428][    T1]  ? __pfx_panic+0x10/0x10
[    7.232458][    T1]  ? ret_from_fork_asm+0x1a/0x30
[    7.232492][    T1]  __warn+0x315/0x4c0
[    7.232513][    T1]  ? drm_mode_config_validate+0x1c6d/0x1e60
[    7.232547][    T1]  ? drm_mode_config_validate+0x1c6d/0x1e60
[    7.232579][    T1]  __report_bug+0x276/0x570
[    7.232605][    T1]  ? drm_mode_config_validate+0x1c6d/0x1e60
[    7.232640][    T1]  ? __pfx___report_bug+0x10/0x10
[    7.232669][    T1]  ? _raw_spin_unlock_irqrestore+0x30/0x80
[    7.232692][    T1]  ? lockdep_hardirqs_on+0x7a/0x110
[    7.232717][    T1]  ? rt_mutex_slowunlock+0x4ee/0xa20
[    7.232752][    T1]  report_bug_entry+0x19a/0x290
[    7.232775][    T1]  ? drm_mode_config_validate+0x1cae/0x1e60
[    7.232806][    T1]  ? drm_mode_config_validate+0x1cb3/0x1e60
[    7.232836][    T1]  handle_bug+0xce/0x200
[    7.232862][    T1]  exc_invalid_op+0x1a/0x50
[    7.232888][    T1]  asm_exc_invalid_op+0x1a/0x20
[    7.232909][    T1] RIP: 0010:drm_mode_config_validate+0x1cae/0x1e60
[    7.232941][    T1] Code: 0f 85 ae 00 00 00 4d 8d 77 10 8b 6d 00 4c 89 f0 48 c1 e8 03 80 3c 18 00 74 08 4c 89 f7 e8 6a 80 ae fc 49 8b 16 4c 89 ef 89 ee <67> 48 0f b9 3a eb 05 e8 a6 39 42 fc 49 bd 00 00 00 00 00 fc ff df
[    7.232959][    T1] RSP: 0000:ffffc90000067810 EFLAGS: 00010246
[    7.232977][    T1] RAX: 1ffff11004e4a808 RBX: dffffc0000000000 RCX: ffff88801d6eddc0
[    7.233001][    T1] RDX: ffff888026f1ab80 RSI: 0000000000000023 RDI: ffffffff8fdc0940
[    7.233017][    T1] RBP: 0000000000000023 R08: 0000000000000000 R09: 0000000000000000
[    7.233030][    T1] R10: dffffc0000000000 R11: fffffbfff1fa18f0 R12: dffffc0000000000
[    7.233046][    T1] R13: ffffffff8fdc0940 R14: ffff888027254040 R15: ffff888027254030
[    7.233087][    T1]  ? debugfs_create_file_full+0x3f/0x60
[    7.233122][    T1]  drm_dev_register+0x7f/0xd80
[    7.233157][    T1]  vkms_create+0x40d/0x4f0
[    7.233182][    T1]  ? __pfx_vkms_init+0x10/0x10
[    7.233204][    T1]  vkms_init+0x57/0x80
[    7.233226][    T1]  do_one_initcall+0x250/0x870
[    7.233255][    T1]  ? __pfx_vkms_init+0x10/0x10
[    7.233277][    T1]  ? __pfx_do_one_initcall+0x10/0x10
[    7.233310][    T1]  ? clockevents_program_event+0x491/0x630
[    7.233337][    T1]  ? __pfx___schedule+0x10/0x10
[    7.233384][    T1]  ? irqentry_exit+0x218/0x8f0
[    7.233406][    T1]  ? lockdep_hardirqs_on+0x7a/0x110
[    7.233428][    T1]  ? irqentry_exit+0x218/0x8f0
[    7.233468][    T1]  ? strlen+0x35/0x70
[    7.233492][    T1]  ? next_arg+0x4a0/0x5e0
[    7.233518][    T1]  ? parameq+0x14d/0x170
[    7.233552][    T1]  ? parse_args+0x9c3/0xad0
[    7.233599][    T1]  ? trace_kmalloc+0x2a/0xf0
[    7.233631][    T1]  ? rcu_is_watching+0x15/0xb0
[    7.233660][    T1]  do_initcall_level+0x10a/0x1a0
[    7.233690][    T1]  ? kernel_init+0x22/0x1d0
[    7.233718][    T1]  do_initcalls+0x59/0xa0
[    7.233747][    T1]  kernel_init_freeable+0x29d/0x3e0
[    7.233775][    T1]  ? __pfx_kernel_init+0x10/0x10
[    7.233805][    T1]  kernel_init+0x22/0x1d0
[    7.233831][    T1]  ? __pfx_kernel_init+0x10/0x10
[    7.233857][    T1]  ret_from_fork+0x514/0xb70
[    7.233888][    T1]  ? __pfx_ret_from_fork+0x10/0x10
[    7.233918][    T1]  ? __switch_to+0xc89/0x1420
[    7.233945][    T1]  ? __pfx_kernel_init+0x10/0x10
[    7.233975][    T1]  ret_from_fork_asm+0x1a/0x30
[    7.234035][    T1]  </TASK>
[    7.234204][    T1] Kernel Offset: disabled


syzkaller build log:
go env (err=<nil>)
AR='ar'
CC='gcc'
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_ENABLED='1'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
CXX='g++'
GCCGO='gccgo'
GO111MODULE='auto'
GOAMD64='v1'
GOARCH='amd64'
GOAUTH='netrc'
GOBIN=''
GOCACHE='/syzkaller/.cache/go-build'
GOCACHEPROG=''
GODEBUG=''
GOENV='/syzkaller/.config/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFIPS140='off'
GOFLAGS=''
GOGCCFLAGS='-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/tmp/go-build3354858300=/tmp/go-build -gno-record-gcc-switches'
GOHOSTARCH='amd64'
GOHOSTOS='linux'
GOINSECURE=''
GOMOD='/syzkaller/jobs-2/linux/gopath/src/github.com/google/syzkaller/go.mod'
GOMODCACHE='/syzkaller/jobs-2/linux/gopath/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='linux'
GOPATH='/syzkaller/jobs-2/linux/gopath'
GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/usr/local/go'
GOSUMDB='sum.golang.org'
GOTELEMETRY='local'
GOTELEMETRYDIR='/syzkaller/.config/go/telemetry'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/usr/local/go/pkg/tool/linux_amd64'
GOVCS=''
GOVERSION='go1.26.0'
GOWORK=''
PKG_CONFIG='pkg-config'

git status (err=<nil>)
HEAD detached at 2130f68232
nothing to commit, working tree clean


tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Makefile:31: run command via tools/syz-env for best compatibility, see:
Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env
go list -f '{{.Stale}}' -ldflags="-s -w -X github.com/google/syzkaller/prog.GitRevision=2130f682322a1c2ef698e3c27a2b97e89e96142f -X github.com/google/syzkaller/prog.gitRevisionDate=20260713-120227"  ./sys/syz-sysgen | grep -q false || go install -ldflags="-s -w -X github.com/google/syzkaller/prog.GitRevision=2130f682322a1c2ef698e3c27a2b97e89e96142f -X github.com/google/syzkaller/prog.gitRevisionDate=20260713-120227"  ./sys/syz-sysgen
make .descriptions
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Makefile:31: run command via tools/syz-env for best compatibility, see:
Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env
bin/syz-sysgen
touch .descriptions
GOOS=linux GOARCH=amd64 go build -ldflags="-s -w -X github.com/google/syzkaller/prog.GitRevision=2130f682322a1c2ef698e3c27a2b97e89e96142f -X github.com/google/syzkaller/prog.gitRevisionDate=20260713-120227"  -o ./bin/linux_amd64/syz-execprog github.com/google/syzkaller/tools/syz-execprog
mkdir -p ./bin/linux_amd64
g++ -o ./bin/linux_amd64/syz-executor executor/executor.cc \
	-m64 -O2 -pthread -Wall -Werror -Wparentheses -Wunused-const-variable -Wframe-larger-than=16384 -Wno-stringop-overflow -Wno-array-bounds -Wno-format-overflow -Wno-unused-but-set-variable -Wno-unused-command-line-argument -static-pie -std=c++17 -I. -Iexecutor/_include   -DGOOS_linux=1 -DGOARCH_amd64=1 \
	-DHOSTGOOS_linux=1 -DGIT_REVISION=\"2130f682322a1c2ef698e3c27a2b97e89e96142f\"
/usr/bin/ld: /tmp/ccNrC6p7.o: in function `Connection::Connect(char const*, char const*)':
executor.cc:(.text._ZN10Connection7ConnectEPKcS1_[_ZN10Connection7ConnectEPKcS1_]+0x386): warning: Using 'gethostbyname' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking
./tools/check-syzos.sh 2>/dev/null


Error text is too large and was truncated, full error text is at:
https://syzkaller.appspot.com/x/error.txt?x=117ff4b9580000


Tested on:

commit:         b8809969 Add linux-next specific files for 20260715
git tree:       linux-next
kernel config:  https://syzkaller.appspot.com/x/.config?x=6a6b64f65d709086
dashboard link: https://syzkaller.appspot.com/bug?extid=2302c5dc59995fbb8089
compiler:       Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8

Note: no patches were applied.

Re: [syzbot] [media?] INFO: trying to register non-static key in __vb2_queue_cancel

[Pimyn Girgis]

Thanks for the report! We created
https://github.com/google/syzkaller/issues/7621 to track the issue.


On Thu, Jul 16, 2026 at 9:59 AM Gautam Bhadoria
<gautambhadori9@gmail.com> wrote:
>
>  The syzbot test request is failing with "lost connection to test
> machine" even when sending #syz test without any patch. This appears
> to be unrelated to the proposed fix and may indicate a problem with
> the current syzbot test environment.
>
> --
> You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to syzkaller-bugs+unsubscribe@googlegroups.com.
> To view this discussion visit https://groups.google.com/d/msgid/syzkaller-bugs/CACugQ7J1QOwmA1uoFUAjdpRMy%2Bs7_bM%2BL3j5K9j9HWUBSDzocg%40mail.gmail.com.



-- 
Ⲡⲟⲓⲙⲏⲛ Ⲅⲉⲱⲣⲅⲓⲟⲥ - Pimyn Girgis
Software Engineer
Kernel Dynamic Analysis
pimyn@google.com