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INFO: rcu detected stall in v4l2_release (2)

Status: auto-obsoleted due to no activity on 2025/09/04 12:19
Subsystems: bpf
[Documentation on labels]
First crash: 91d, last: 91d
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in v4l2_release media mm 1 3 284d 344d 0/29 auto-obsoleted due to no activity on 2025/02/23 13:46
linux-6.1 INFO: rcu detected stall in v4l2_release 1 1 1d21h 1d21h 0/3 upstream: reported on 2025/09/03 22:11

Sample crash report:
ip6_tunnel: ip6gre1 xmit: Local address not yet configured!
ip6_tunnel: ip6gre1 xmit: Local address not yet configured!
ip6_tunnel: ip6gre1 xmit: Local address not yet configured!
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P7849/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=19445, q=368 ncpus=2)
task:syz.2.862       state:R  running task     stack:22952 pid:7849  tgid:7849  ppid:5831   task_flags:0x400040 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x16a2/0x4cb0 kernel/sched/core.c:6785
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7108
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_release+0x2b5/0x3e0 kernel/locking/lockdep.c:5896
Code: 51 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 75 56 f7 c3 00 02 00 00 74 01 fb 65 48 8b 05 bb 38 fb 10 <48> 3b 44 24 28 0f 85 8b 00 00 00 48 83 c4 30 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9000aa67708 EFLAGS: 00000206
RAX: b875391b2dafaa00 RBX: 0000000000000202 RCX: b875391b2dafaa00
RDX: 0000000000000003 RSI: ffffffff8db54ebc RDI: ffffffff8be1af80
RBP: ffff888028cde568 R08: 0000000000000000 R09: ffffffff81cf3396
R10: ffffc9000aa67858 R11: ffffffff81ace580 R12: 0000000000000003
R13: 0000000000000003 R14: ffffffff8e13f060 R15: ffff888028cdda00
 rcu_lock_release include/linux/rcupdate.h:341 [inline]
 rcu_read_unlock include/linux/rcupdate.h:871 [inline]
 is_bpf_text_address+0x28d/0x2b0 kernel/bpf/core.c:774
 kernel_text_address+0xa5/0xe0 kernel/extable.c:125
 __kernel_text_address+0xd/0x40 kernel/extable.c:79
 unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:369
 arch_stack_walk+0xfc/0x150 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2381 [inline]
 slab_free mm/slub.c:4643 [inline]
 kfree+0x18e/0x440 mm/slub.c:4842
 __vb2_queue_free+0x906/0xb00 drivers/media/common/videobuf2/videobuf2-core.c:691
 vb2_core_queue_release+0x6b/0x150 drivers/media/common/videobuf2/videobuf2-core.c:2695
 vb2_queue_release drivers/media/common/videobuf2/videobuf2-v4l2.c:956 [inline]
 _vb2_fop_release drivers/media/common/videobuf2/videobuf2-v4l2.c:1158 [inline]
 vb2_fop_release+0x16e/0x200 drivers/media/common/videobuf2/videobuf2-v4l2.c:1172
 v4l2_release+0x1ea/0x3b0 drivers/media/v4l2-core/v4l2-dev.c:458
 __fput+0x449/0xa70 fs/file_table.c:465
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f33e558e929
RSP: 002b:00007ffdf7710ad8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 0000000000023de2 RCX: 00007f33e558e929
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f33e57b7ba0 R08: 0000000000000001 R09: 00000004f7710dcf
R10: 00007f33e5400000 R11: 0000000000000246 R12: 00007f33e57b5fac
R13: 00007f33e57b5fa0 R14: ffffffffffffffff R15: 00007ffdf7710bf0
 </TASK>
rcu: rcu_preempt kthread starved for 10500 jiffies! g19445 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:27320 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x16a2/0x4cb0 kernel/sched/core.c:6785
 __schedule_loop kernel/sched/core.c:6863 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6878
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 7855 Comm: syz.4.865 Not tainted 6.15.0-syzkaller-12426-ge271ed52b344 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0xf69/0x12d0 kernel/smp.c:885
Code: 00 45 8b 2f 44 89 ee 83 e6 01 31 ff e8 50 78 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 fb 73 0b 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 e0 73 0b
RSP: 0018:ffffc9000a9e75a0 EFLAGS: 00000293
RAX: ffffffff81b4d6f0 RBX: ffff8880b863c9c0 RCX: ffff88802abe0000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000a9e7700 R08: ffffffff8f9fd6f7 R09: 1ffffffff1f3fade
R10: dffffc0000000000 R11: fffffbfff1f3fadf R12: 1ffff110170e825d
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b87412e8
FS:  0000000000000000(0000) GS:ffff888125c89000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3b2c97 CR3: 000000000df38000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
 flush_tlb_mm_range+0x6b1/0x12c0 arch/x86/mm/tlb.c:1451
 tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
 tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:490 [inline]
 tlb_flush_mmu+0x1a7/0x680 mm/mmu_gather.c:403
 tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497
 free_ldt_pgtables+0x17b/0x320 arch/x86/kernel/ldt.c:411
 arch_exit_mmap arch/x86/include/asm/mmu_context.h:234 [inline]
 exit_mmap+0x17c/0xb50 mm/mmap.c:1270
 __mmput+0x118/0x420 kernel/fork.c:1121
 exit_mm+0x1da/0x2c0 kernel/exit.c:581
 do_exit+0x640/0x22e0 kernel/exit.c:943
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1104
 __do_sys_exit_group kernel/exit.c:1115 [inline]
 __se_sys_exit_group kernel/exit.c:1113 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1113
 x64_sys_call+0x21ba/0x21c0 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbc7398e929
Code: Unable to access opcode bytes at 0x7fbc7398e8ff.
RSP: 002b:00007ffc9e618678 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbc7398e929
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffc9e6186dc R08: 000000049e61876f R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 000000000000008f
R13: 00000000000927c0 R14: 0000000000023d31 R15: 00007ffc9e618730
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/06 12:14 upstream e271ed52b344 f61267d4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in v4l2_release
* Struck through repros no longer work on HEAD.