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INFO: rcu detected stall in sys_epoll_ctl (2)

Status: auto-obsoleted due to no activity on 2024/06/25 13:25
Subsystems: fs
[Documentation on labels]
First crash: 307d, last: 307d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_epoll_ctl fs 1 1259d 1259d 0/28 auto-closed as invalid on 2021/10/17 15:58

Sample crash report:
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 0, t=10502 jiffies, g=35089, q=170 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294971853-4294961351), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10502 jiffies! g35089 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:28736 pid:16    tgid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5409 [inline]
 __schedule+0xf15/0x5c70 kernel/sched/core.c:6736
 __schedule_loop kernel/sched/core.c:6813 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6828
 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2572
 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:1663
 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:1862
 kthread+0x2c1/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 10609 Comm: syz-executor.1 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x8/0x20 kernel/kcov.c:290
Code: bf 06 00 00 00 e9 b8 fe ff ff 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 0c 24 <40> 0f b6 d6 40 0f b6 f7 bf 01 00 00 00 e9 86 fe ff ff 66 0f 1f 44
RSP: 0018:ffffc90000a08df8 EFLAGS: 00000046
RAX: 0000000000000001 RBX: ffff8880b952cac0 RCX: ffffffff817a4838
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff88805ae66340 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffff8b0f38c0 R12: 0000000000000001
R13: 000000000003d3cc R14: 0000000000000000 R15: ffffffff88e73220
FS:  00007fd8822366c0(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30521000 CR3: 0000000029cda000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 trace_hrtimer_start include/trace/events/timer.h:222 [inline]
 debug_activate kernel/time/hrtimer.c:479 [inline]
 enqueue_hrtimer+0x2f8/0x390 kernel/time/hrtimer.c:1090
 __run_hrtimer kernel/time/hrtimer.c:1709 [inline]
 __hrtimer_run_queues+0xa15/0xc20 kernel/time/hrtimer.c:1756
 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1818
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline]
 __sysvec_apic_timer_interrupt+0x10f/0x410 arch/x86/kernel/apic/apic.c:1049
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
 sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1043
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__fget_light+0x7c/0x210 fs/file.c:1145
Code: 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 0f b6 14 02 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 46 01 00 00 8b 5d 00 <bf> 01 00 00 00 89 de e8 a8 e2 8c ff 83 fb 01 0f 85 08 01 00 00 e8
RSP: 0018:ffffc90002f4fcd8 EFLAGS: 00000246
RAX: 0000000000000003 RBX: 0000000000000002 RCX: ffffffff820010af
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88801faad2c0
RBP: ffff88801faad2c0 R08: 0000000000000000 R09: ffffed1003f55a58
R10: ffff88801faad2c3 R11: 0000000000000000 R12: 0000000000000004
R13: 0000000000004000 R14: dffffc0000000000 R15: 0000000000000004
 fdget include/linux/file.h:66 [inline]
 do_epoll_ctl+0xba/0x3570 fs/eventpoll.c:2232
 __do_sys_epoll_ctl fs/eventpoll.c:2386 [inline]
 __se_sys_epoll_ctl fs/eventpoll.c:2377 [inline]
 __x64_sys_epoll_ctl+0x15d/0x1e0 fs/eventpoll.c:2377
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7fd88147dda9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd8822360c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e9
RAX: ffffffffffffffda RBX: 00007fd8815abf80 RCX: 00007fd88147dda9
RDX: ffffffffffffffff RSI: 0000000000000001 RDI: 0000000000000004
RBP: 00007fd8814ca47a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020000140 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fd8815abf80 R15: 00007ffcfa556058
 </TASK>
vkms_vblank_simulate: vblank timer overrun

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/03/27 13:23 upstream fe46a7dd189e 454571b6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in sys_epoll_ctl
* Struck through repros no longer work on HEAD.