INFO: rcu detected stall in handle_softirqs

Status: auto-obsoleted due to no activity on 2024/11/01 18:35
Reported-by: syzbot+998a214b918c9558dd14@syzkaller.appspotmail.com
First crash: 779d, last: 766d
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in handle_softirqs (3) prio:low lvs block 1 syz, C error 43 5d04h 92d 0/29 upstream: reported C repro on 2026/05/29 19:50
upstream INFO: rcu detected stall in handle_softirqs net 1 syz, C done done 34 636d 841d 0/29 auto-obsoleted due to no activity on 2025/02/26 20:58
upstream INFO: rcu detected stall in handle_softirqs (2) mm 1 6 391d 519d 0/29 auto-obsoleted due to no activity on 2025/11/02 03:12
linux-5.15 BUG: soft lockup in handle_softirqs 1 1 452d 452d 0/3 auto-obsoleted due to no activity on 2025/09/12 05:21
linux-6.1 BUG: soft lockup in handle_softirqs 1 1 374d 374d 0/3 auto-obsoleted due to no activity on 2025/11/28 21:20

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-....: (1 GPs behind) idle=a05/1/0x4000000000000000 softirq=59286/59289 fqs=140 
	(detected by 0, t=10502 jiffies, g=81733, q=1934)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 11472 Comm: kworker/1:21 Not tainted 5.15.163-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Workqueue: rcu_gp process_srcu
RIP: 0010:check_kcov_mode kernel/kcov.c:163 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:218 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x28/0x80 kernel/kcov.c:270
Code: 00 00 4c 8b 04 24 65 48 8b 15 44 0f 82 7e 65 8b 05 45 0f 82 7e a9 00 01 ff 00 74 10 a9 00 01 00 00 74 5b 83 ba 34 16 00 00 00 <74> 52 8b 82 10 16 00 00 83 f8 03 75 47 48 8b 8a 18 16 00 00 44 8b
RSP: 0018:ffffc90000dd0938 EFLAGS: 00000046
RAX: 0000000000010101 RBX: 0000000000000001 RCX: ffffffff8835ee3d
RDX: ffff88801c0b5940 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000dd0a10 R08: ffffffff8835ee66 R09: ffffed100b2c5232
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888059629000
R13: dffffc0000000000 R14: 1ffff920001ba12c R15: 000000bf6f777b00
FS:  0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3300cff8 CR3: 000000007c764000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 arch_test_and_set_bit arch/x86/include/asm/bitops.h:138 [inline]
 test_and_set_bit include/asm-generic/bitops/instrumented-atomic.h:71 [inline]
 __netif_schedule+0xb6/0x310 net/core/dev.c:3073
 advance_sched+0x750/0x940 net/sched/sch_taprio.c:770
 __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+0x3e/0xb0 arch/x86/kernel/apic/apic.c:1096
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:ffs arch/x86/include/asm/bitops.h:297 [inline]
RIP: 0010:handle_softirqs+0x1d6/0x930 kernel/softirq.c:546
Code: 24 78 4c 89 7c 24 70 0f b7 db 48 c7 c7 e0 10 8a 8a e8 8e 3e d1 08 65 66 c7 05 44 15 b6 7e 00 00 e8 9f 5a 39 00 fb 89 5c 24 34 <b8> ff ff ff ff 0f bc 44 24 34 41 89 c6 41 ff c6 0f 85 f3 00 00 00
RSP: 0018:ffffc90000dd0e20 EFLAGS: 00000282
RAX: 62edeb9be813ae00 RBX: 0000000000000386 RCX: ffffffff913f1f03
RDX: dffffc0000000000 RSI: ffffffff8a8b2a00 RDI: ffffffff8ad8f700
RBP: ffffc90000dd0f30 R08: ffffffff8186de90 R09: ffffffff8f5fd048
R10: ffffffff8f5fd058 R11: ffffffff8f5fd050 R12: ffff88801c0b5940
R13: 1ffff920001ba1e8 R14: dffffc0000000000 R15: 1ffff920001ba1d8
 __do_softirq kernel/softirq.c:592 [inline]
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x157/0x240 kernel/softirq.c:641
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:653
 sysvec_apic_timer_interrupt+0x91/0xb0 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_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: 21 80 f6 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 de a4 3a f7 48 89 df e8 b6 f8 3b f7 e8 01 b1 5e f7 fb bf 01 00 00 00 <e8> 16 3d 2f f7 65 8b 05 57 42 da 75 85 c0 74 02 5b c3 e8 24 5f d8
RSP: 0018:ffffc900030d7c50 EFLAGS: 00000282
RAX: 62edeb9be813ae00 RBX: ffff8880b9b39b40 RCX: ffffffff913f1f03
RDX: dffffc0000000000 RSI: ffffffff8a8b2a00 RDI: 0000000000000001
RBP: ffffc900030d7dc8 R08: ffffffff8186de90 R09: ffffed1017367369
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffffffff8c9f20b0 R14: 0000000000000080 R15: ffff88805757e628
 process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: rcu_preempt kthread starved for 945 jiffies! g81733 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:26488 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:
NMI backtrace for cpu 0
CPU: 0 PID: 1069 Comm: kworker/0:2 Not tainted 5.15.163-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Workqueue: events bpf_prog_free_deferred
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 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:1818
 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:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:193
Code: 1f 84 00 00 00 00 00 0f 1f 00 53 48 89 fb e8 17 00 00 00 48 8b 3d 18 1b 64 0c 48 89 de 5b e9 77 fb 48 00 cc cc cc cc cc cc cc <48> 8b 04 24 65 48 8b 0d a4 11 82 7e 65 8b 15 a5 11 82 7e f7 c2 00
RSP: 0018:ffffc900045ef878 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 1ffff110173680b9 RCX: ffff88801c32bb80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900045ef9b0 R08: ffffffff81749214 R09: fffffbfff1f7f419
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000001
R13: ffff8880b9b405c8 R14: ffff8880b9a3b3c0 R15: 0000000000000001
 csd_lock_wait kernel/smp.c:440 [inline]
 smp_call_function_many_cond+0xab4/0xd90 kernel/smp.c:969
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1135
 on_each_cpu include/linux/smp.h:71 [inline]
 flush_tlb_kernel_range+0x197/0x230 arch/x86/mm/tlb.c:1033
 __purge_vmap_area_lazy+0x15ae/0x1740 mm/vmalloc.c:1704
 _vm_unmap_aliases+0x453/0x4e0 mm/vmalloc.c:2107
 vm_remove_mappings mm/vmalloc.c:2584 [inline]
 __vunmap+0x72e/0xa20 mm/vmalloc.c:2611
 bpf_jit_binary_free kernel/bpf/core.c:914 [inline]
 bpf_jit_free+0x92/0x180 kernel/bpf/core.c:927
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/07/24 18:34 linux-5.15.y 7c6d66f0266f d1a1b0ca .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in handle_softirqs
2024/07/11 21:52 linux-5.15.y f45bea23c39c eaeb5c15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in handle_softirqs
* Struck through repros no longer work on HEAD.