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INFO: rcu detected stall in sys_pselect6

Status: upstream: reported on 2024/07/29 04:58
Reported-by: syzbot+01061f59f7ac229ec4d3@syzkaller.appspotmail.com
First crash: 68d, last: 68d
▶ ▼ Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_pselect6 (2) usb ext4 input syz 14 7h26m 4d13h 0/28 upstream: reported syz repro on 2024/10/01 09:04
upstream INFO: rcu detected stall in sys_pselect6 fs 1 1125d 1125d 0/28 auto-closed as invalid on 2021/12/05 02:59

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 ticks this GP) idle=dc5/1/0x4000000000000000 softirq=50403/50403 fqs=0 
	(detected by 0, t=10502 jiffies, g=64249, q=621)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 3558 Comm: syz-executor Not tainted 5.15.164-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:rb_insert_color_cached include/linux/rbtree.h:113 [inline]
RIP: 0010:rb_add_cached include/linux/rbtree.h:183 [inline]
RIP: 0010:timerqueue_add+0x24b/0x280 lib/timerqueue.c:40
Code: 64 24 08 49 8d 5c 24 08 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 48 89 df e8 28 44 9c fd 4c 89 3b <4d> 85 ff 0f 95 c3 4c 89 ff 4c 89 e6 e8 e4 4f ff ff 89 d8 48 83 c4
RSP: 0018:ffffc90000dd0cc0 EFLAGS: 00000046
RAX: 1ffff1101736546b RBX: ffff8880b9b2a358 RCX: dffffc0000000000
RDX: 0000000000000018 RSI: 0000000000000000 RDI: ffff88801f10e358
RBP: 1ffff11003e21c68 R08: dffffc0000000000 R09: ffff88801f10e340
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880b9b2a350
R13: ffff8880b9b2a350 R14: 0000000000000000 R15: ffff88801f10e340
FS:  0000555555c94500(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020007000 CR3: 000000001af67000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 enqueue_hrtimer+0x1a0/0x390 kernel/time/hrtimer.c:1092
 __run_hrtimer kernel/time/hrtimer.c:1703 [inline]
 __hrtimer_run_queues+0x6b6/0xcf0 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 f2 90 8d f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 97 c6 1a f7 65 8b 05 58 cb c5 75 85 c0 74 3f 48 c7 04 24 0e 36
RSP: 0018:ffffc90003077580 EFLAGS: 00000206
RAX: d07c8722cd1e4d00 RBX: 1ffff9200060eeb4 RCX: ffffffff91467f03
RDX: dffffc0000000000 RSI: ffffffff8a8b2a00 RDI: 0000000000000001
RBP: ffffc90003077610 R08: ffffffff8186e200 R09: ffffed100b0cfc93
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff9200060eeb0 R14: ffffc900030775a0 R15: 0000000000000246
 free_poll_entry fs/select.c:134 [inline]
 poll_freewait+0xb5/0x240 fs/select.c:143
 do_select+0x1691/0x17f0 fs/select.c:611
 core_sys_select+0x699/0x8b0 fs/select.c:680
 do_pselect fs/select.c:762 [inline]
 __do_sys_pselect6 fs/select.c:803 [inline]
 __se_sys_pselect6+0x37f/0x470 fs/select.c:794
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f280913c05c
Code: 29 44 24 30 80 3d fb f4 15 00 00 4c 89 4c 24 40 4c 8d 4c 24 40 48 c7 44 24 48 08 00 00 00 74 2e 4c 89 ea b8 0e 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 7c 48 8b 54 24 58 64 48 2b 14 25 28 00 00 00
RSP: 002b:00007ffc8c6bd3c0 EFLAGS: 00000202 ORIG_RAX: 000000000000010e
RAX: ffffffffffffffda RBX: 0000000000004000 RCX: 00007f280913c05c
RDX: 0000000000000000 RSI: 00007ffc8c6bd4e0 RDI: 0000000000000025
RBP: 00007ffc8c6bd8f0 R08: 00007ffc8c6bd3f0 R09: 00007ffc8c6bd400
R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffc8c6bd750
R13: 0000000000000000 R14: 585858582e7a7973 R15: 00007ffc8c6bd7c0
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g64249 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=35096
rcu: rcu_preempt kthread starved for 10502 jiffies! g64249 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27064 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1f0 kernel/sched/core.c:6459
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </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: 3558 Comm: syz-executor Not tainted 5.15.164-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:__lock_acquire+0xf46/0x1ff0 kernel/locking/lockdep.c:5007
Code: cb 01 d6 29 da 89 dd c1 c5 13 31 d5 01 f3 29 ee 01 eb c1 c5 04 31 f5 48 c1 e5 20 48 c7 c0 c8 7f e9 8d 48 c1 e8 03 0f b6 04 38 <84> c0 0f 85 88 0b 00 00 48 09 dd 83 3d 00 be 86 0c 00 4c 8b 7c 24
RSP: 0018:ffffc90000dd0a60 EFLAGS: 00000806
RAX: 0000000000000000 RBX: 000000005a07258c RCX: 000000000328287d
RDX: 000000003631f396 RSI: 00000000696cd562 RDI: dffffc0000000000
RBP: 5f17096b00000000 R08: dffffc0000000000 R09: fffffbfff1f8e04b
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: ffff88807a88a8a8 R14: 1ffff1100f511514 R15: 0000000000000c9e
FS:  0000555555c94500(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020007000 CR3: 000000001af67000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:363 [inline]
 advance_sched+0x47/0x940 net/sched/sch_taprio.c:716
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x598/0xcf0 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 f2 90 8d f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 97 c6 1a f7 65 8b 05 58 cb c5 75 85 c0 74 3f 48 c7 04 24 0e 36
RSP: 0018:ffffc90003077580 EFLAGS: 00000206
RAX: d07c8722cd1e4d00 RBX: 1ffff9200060eeb4 RCX: ffffffff91467f03
RDX: dffffc0000000000 RSI: ffffffff8a8b2a00 RDI: 0000000000000001
RBP: ffffc90003077610 R08: ffffffff8186e200 R09: ffffed100b0cfc93
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff9200060eeb0 R14: ffffc900030775a0 R15: 0000000000000246
 free_poll_entry fs/select.c:134 [inline]
 poll_freewait+0xb5/0x240 fs/select.c:143
 do_select+0x1691/0x17f0 fs/select.c:611
 core_sys_select+0x699/0x8b0 fs/select.c:680
 do_pselect fs/select.c:762 [inline]
 __do_sys_pselect6 fs/select.c:803 [inline]
 __se_sys_pselect6+0x37f/0x470 fs/select.c:794
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f280913c05c
Code: 29 44 24 30 80 3d fb f4 15 00 00 4c 89 4c 24 40 4c 8d 4c 24 40 48 c7 44 24 48 08 00 00 00 74 2e 4c 89 ea b8 0e 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 7c 48 8b 54 24 58 64 48 2b 14 25 28 00 00 00
RSP: 002b:00007ffc8c6bd3c0 EFLAGS: 00000202 ORIG_RAX: 000000000000010e
RAX: ffffffffffffffda RBX: 0000000000004000 RCX: 00007f280913c05c
RDX: 0000000000000000 RSI: 00007ffc8c6bd4e0 RDI: 0000000000000025
RBP: 00007ffc8c6bd8f0 R08: 00007ffc8c6bd3f0 R09: 00007ffc8c6bd400
R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffc8c6bd750
R13: 0000000000000000 R14: 585858582e7a7973 R15: 00007ffc8c6bd7c0
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/07/29 04:57 linux-5.15.y 7e89efd3ae1c 46eb10b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_pselect6
* Struck through repros no longer work on HEAD.