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INFO: rcu detected stall in task_work_run

Status: auto-obsoleted due to no activity on 2024/07/04 00:01
Reported-by: syzbot+52f5aff31104af95fbe1@syzkaller.appspotmail.com
First crash: 715d, last: 715d
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: rcu detected stall in task_work_run (3) origin:lts-only 1 syz error 7 1d17h 178d 0/3 upstream: reported syz repro on 2025/09/13 23:38
linux-6.1 INFO: rcu detected stall in task_work_run origin:lts-only 1 C error 2 23d 188d 0/3 upstream: reported C repro on 2025/09/04 00:43
linux-5.15 INFO: rcu detected stall in task_work_run (2) origin:lts-only 1 syz error 1 464d 464d 0/3 auto-obsoleted due to no activity on 2025/03/24 21:44
upstream INFO: rcu detected stall in task_work_run kernel 1 2 944d 994d 0/29 auto-obsoleted due to no activity on 2023/11/07 12:15

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=1f1/1/0x4000000000000000 softirq=48029/48033 fqs=1 
	(detected by 1, t=10506 jiffies, g=56953, q=215)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 12061 Comm: syz-executor.4 Not tainted 5.15.152-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
RIP: 0010:mark_usage kernel/locking/lockdep.c:4485 [inline]
RIP: 0010:__lock_acquire+0xb75/0x1ff0 kernel/locking/lockdep.c:4966
Code: 74 23 48 89 ef 48 8b 74 24 08 31 d2 e8 74 5b 00 00 31 f6 48 ba 00 00 00 00 00 fc ff df 85 c0 0f 84 d7 09 00 00 48 8b 44 24 68 <0f> b6 04 10 84 c0 0f 85 fe 10 00 00 48 8b 44 24 10 83 38 00 74 24
RSP: 0018:ffffc90000007a80 EFLAGS: 00000002
RAX: 1ffff1100257f15a RBX: 1ffff1100257f162 RCX: ffffffff8162f928
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffffffff8fbcf0c8
RBP: ffff888012bf8000 R08: dffffc0000000000 R09: fffffbfff1f79e1a
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: ffff888012bf8ae8 R14: 1ffff1100257f162 R15: ffff888012bf8b10
FS:  00005555564ad480(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000440 CR3: 00000000776aa000 CR4: 00000000003506f0
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_irq include/linux/spinlock_api_smp.h:128 [inline]
 _raw_spin_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:170
 __run_hrtimer kernel/time/hrtimer.c:1690 [inline]
 __hrtimer_run_queues+0x662/0xcf0 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:call_rcu+0x7aa/0xa70 kernel/rcu/tree.c:3088
Code: 3c 03 00 74 08 4c 89 f7 e8 63 de 5e 00 f6 84 24 81 00 00 00 02 75 59 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <48> b8 00 00 00 00 00 fc ff df 4a c7 04 28 00 00 00 00 66 42 c7 44
RSP: 0018:ffffc90003477d60 EFLAGS: 00000206
RAX: dffffc0000000000 RBX: 1ffff9200068efbc RCX: ffffffff913c6f03
RDX: dffffc0000000000 RSI: ffffffff8a8b1500 RDI: ffffffff8ad88f00
RBP: ffffc90003477e68 R08: ffffffff8186b7e0 R09: fffffbfff1bc71b6
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff1101734764c
R13: 1ffff9200068efb8 R14: ffffc90003477de0 R15: 0000000000000246
 task_work_run+0x129/0x1a0 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:175
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x5d/0x250 kernel/entry/common.c:301
 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fb2ae17dc9a
Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 03 7f 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 63 7f 02 00 8b 44 24
RSP: 002b:00007ffff90c43e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007fb2ae17dc9a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000032 R08: 0000001b2fb20000 R09: 0000000000000033
R10: 0000000081a6f1eb R11: 0000000000000293 R12: 00007fb2add01648
R13: ffffffffffffffff R14: 00007fb2add01000 R15: 000000000004a321
 </TASK>
rcu: rcu_preempt kthread starved for 10500 jiffies! g56953 f0x0 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:27000 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:1884
 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:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 12068 Comm: syz-executor.1 Not tainted 5.15.152-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3932 [inline]
 rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619
 update_process_times+0x196/0x200 kernel/time/timer.c:1788
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x55b/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:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_many_cond+0xa93/0xd90 kernel/smp.c:969
Code: 04 03 84 c0 0f 85 84 00 00 00 45 8b 7d 00 44 89 fe 83 e6 01 31 ff e8 ac ce 0b 00 41 83 e7 01 75 07 e8 41 cb 0b 00 eb 41 f3 90 <48> b8 00 00 00 00 00 fc ff df 0f b6 04 03 84 c0 75 11 41 f7 45 00
RSP: 0018:ffffc90002f37260 EFLAGS: 00000246
RAX: ffffffff81746eb4 RBX: 1ffff11017348541 RCX: 0000000000040000
RDX: ffffc9000f510000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: ffffc90002f373a0 R08: ffffffff81746e84 R09: fffffbfff1f79e1a
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: ffff8880b9a42a08 R14: ffff8880b9b3b380 R15: 0000000000000001
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1135
 __purge_vmap_area_lazy+0x294/0x1740 mm/vmalloc.c:1683
 _vm_unmap_aliases+0x453/0x4e0 mm/vmalloc.c:2107
 change_page_attr_set_clr+0x308/0x1050 arch/x86/mm/pat/set_memory.c:1740
 change_page_attr_clear arch/x86/mm/pat/set_memory.c:1797 [inline]
 set_memory_ro+0xa1/0xe0 arch/x86/mm/pat/set_memory.c:1943
 bpf_jit_binary_lock_ro include/linux/filter.h:888 [inline]
 bpf_int_jit_compile+0xbf57/0xc6e0 arch/x86/net/bpf_jit_comp.c:2372
 bpf_prog_select_runtime+0x6e2/0x9b0 kernel/bpf/core.c:1930
 bpf_migrate_filter net/core/filter.c:1296 [inline]
 bpf_prepare_filter+0x10d0/0x13d0 net/core/filter.c:1344
 bpf_prog_create_from_user+0x2a7/0x3d0 net/core/filter.c:1438
 seccomp_prepare_filter kernel/seccomp.c:669 [inline]
 seccomp_prepare_user_filter kernel/seccomp.c:706 [inline]
 seccomp_set_mode_filter kernel/seccomp.c:1834 [inline]
 do_seccomp+0x8cf/0x1790 kernel/seccomp.c:1954
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f0418f2ada9
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:00007f04174ab0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000013d
RAX: ffffffffffffffda RBX: 00007f0419058f80 RCX: 00007f0418f2ada9
RDX: 0000000020000040 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 00007f0418f7747a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f0419058f80 R15: 00007fffc0e6e4c8
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/03/26 00:00 linux-5.15.y b95c01af2113 bcd9b39f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in task_work_run
* Struck through repros no longer work on HEAD.