INFO: rcu detected stall in handle_softirqs (2)

Status: auto-obsoleted due to no activity on 2025/11/02 03:12
Subsystems: mm
[Documentation on labels]
First crash: 492d, last: 363d
▶ ▼ 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 netfilter 1 syz, C error 34 2h41m 65d 0/29 upstream: reported C repro on 2026/05/29 19:50
linux-5.15 INFO: rcu detected stall in handle_softirqs 1 2 739d 751d 0/3 auto-obsoleted due to no activity on 2024/11/01 18:35
upstream INFO: rcu detected stall in handle_softirqs net 1 syz, C done done 34 609d 813d 0/29 auto-obsoleted due to no activity on 2025/02/26 20:58
linux-5.15 BUG: soft lockup in handle_softirqs 1 1 424d 424d 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 346d 346d 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: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P49/1:b..l P9522/1:b..l P14612/1:b..l P5840/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=51729, q=537 ncpus=2)
task:syz-executor    state:R  running task     stack:23784 pid:5840  tgid:5840  ppid:5837   task_flags:0x400140 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6961
 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7145
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 copy_pte_range mm/memory.c:1201 [inline]
 copy_pmd_range mm/memory.c:1261 [inline]
 copy_pud_range mm/memory.c:1298 [inline]
 copy_p4d_range mm/memory.c:1322 [inline]
 copy_page_range+0x1f7d/0x5c80 mm/memory.c:1410
 dup_mmap+0xe88/0x21d0 mm/mmap.c:1834
 dup_mm kernel/fork.c:1483 [inline]
 copy_mm kernel/fork.c:1535 [inline]
 copy_process+0x4081/0x7690 kernel/fork.c:2173
 kernel_clone+0xfc/0x930 kernel/fork.c:2603
 __do_sys_clone+0xce/0x120 kernel/fork.c:2746
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f88c0f853d3
RSP: 002b:00007ffcf522ed38 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f88c0f853d3
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 000055555d3f67d0 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000005a R14: 00000000000d36c6 R15: 00007ffcf522eed0
 </TASK>
task:syz.3.2159      state:R  running task     stack:26920 pid:14612 tgid:14612 ppid:5852   task_flags:0x400040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6961
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7288
 irqentry_exit+0x36/0x90 kernel/entry/common.c:197
 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707
RIP: 0010:its_return_thunk+0x0/0x10 arch/x86/lib/retpoline.S:412
Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc <c3> cc 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 e9 db a3 96 f5 cc
RSP: 0018:ffffc900037a7240 EFLAGS: 00000292
RAX: ffffffff914043ba RBX: 0000000000000001 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff90bbd44c
RBP: ffffc900037a7350 R08: ffffffff914043c0 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000006b08 R12: ffffc900037a7358
R13: ffffc900037a7308 R14: ffffc900037a733d R15: ffffffff816b08f3
 orc_find arch/x86/kernel/unwind_orc.c:227 [inline]
 unwind_next_frame+0x2ec/0x20a0 arch/x86/kernel/unwind_orc.c:494
 __unwind_start+0x45f/0x7f0 arch/x86/kernel/unwind_orc.c:758
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0x73/0x100 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4180 [inline]
 slab_alloc_node mm/slub.c:4229 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4236
 mt_alloc_one lib/maple_tree.c:176 [inline]
 mas_alloc_nodes+0x18b/0x8b0 lib/maple_tree.c:1255
 mas_node_count_gfp+0x105/0x130 lib/maple_tree.c:1337
 mas_preallocate+0x7e0/0xde0 lib/maple_tree.c:5537
 vma_iter_prealloc mm/vma.h:462 [inline]
 __split_vma+0x34a/0x1070 mm/vma.c:528
 split_vma mm/vma.c:598 [inline]
 vma_modify+0x16dc/0x2030 mm/vma.c:1623
 vma_modify_flags+0x212/0x2d0 mm/vma.c:1649
 mprotect_fixup+0x2b3/0xb10 mm/mprotect.c:819
 do_mprotect_pkey+0x9ca/0xd50 mm/mprotect.c:993
 __do_sys_mprotect mm/mprotect.c:1014 [inline]
 __se_sys_mprotect mm/mprotect.c:1011 [inline]
 __x64_sys_mprotect+0x78/0xc0 mm/mprotect.c:1011
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1dc9b8ec27
RSP: 002b:00007fff22ab0888 EFLAGS: 00000206 ORIG_RAX: 000000000000000a
RAX: ffffffffffffffda RBX: 00007f1dca9656c0 RCX: 00007f1dc9b8ec27
RDX: 0000000000000003 RSI: 0000000000020000 RDI: 00007f1dca946000
RBP: 0000000000000000 R08: 00000000ffffffff R09: 0000000000000000
R10: 0000000000021000 R11: 0000000000000206 R12: 00007fff22ab09e0
R13: ffffffffffffffc0 R14: 0000000000001000 R15: 0000000000000000
 </TASK>
task:syz-executor    state:R  running task     stack:24088 pid:9522  tgid:9522  ppid:9489   task_flags:0x400140 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6961
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7288
 irqentry_exit+0x36/0x90 kernel/entry/common.c:197
 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:86 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:104 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:129 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:161 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x146/0x1b0 mm/kasan/generic.c:189
Code: 83 c0 01 49 89 d3 48 39 d0 74 11 80 38 00 74 ef 4d 8d 1c 2c 48 89 c2 48 85 c0 75 ad 48 89 da 4c 89 d8 4c 29 da e9 46 ff ff ff <48> 85 d2 74 18 48 01 ea eb 09 48 83 c0 01 48 39 d0 74 0a 80 38 00
RSP: 0018:ffffc9000c3a70c0 EFLAGS: 00000283
RAX: ffffed1003a41e87 RBX: ffffed1003a41e88 RCX: ffffffff822da559
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffff88801d20f43c
RBP: ffffed1003a41e87 R08: 0000000000000000 R09: ffffed1003a41e87
R10: ffff88801d20f43f R11: 0000000000000000 R12: ffff88801d20f3f0
R13: ffff88801d20f43c R14: 0000000000000000 R15: dffffc0000000000
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
 __page_table_check_zero+0x279/0x5d0 mm/page_table_check.c:143
 page_table_check_alloc include/linux/page_table_check.h:35 [inline]
 post_alloc_hook+0x1af/0x230 mm/page_alloc.c:1852
 prep_new_page mm/page_alloc.c:1859 [inline]
 get_page_from_freelist+0x132b/0x38e0 mm/page_alloc.c:3858
 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:5148
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416
 alloc_frozen_pages_noprof mm/mempolicy.c:2487 [inline]
 alloc_pages_noprof+0x131/0x390 mm/mempolicy.c:2507
 pagetable_alloc_noprof include/linux/mm.h:2879 [inline]
 __pte_alloc_one_noprof include/asm-generic/pgalloc.h:75 [inline]
 pte_alloc_one+0x1c/0x3a0 arch/x86/mm/pgtable.c:18
 __pte_alloc+0x6d/0x3c0 mm/memory.c:452
 copy_pte_range mm/memory.c:1107 [inline]
 copy_pmd_range mm/memory.c:1261 [inline]
 copy_pud_range mm/memory.c:1298 [inline]
 copy_p4d_range mm/memory.c:1322 [inline]
 copy_page_range+0x3b83/0x5c80 mm/memory.c:1410
 dup_mmap+0xe88/0x21d0 mm/mmap.c:1834
 dup_mm kernel/fork.c:1483 [inline]
 copy_mm kernel/fork.c:1535 [inline]
 copy_process+0x4081/0x7690 kernel/fork.c:2173
 kernel_clone+0xfc/0x930 kernel/fork.c:2603
 __do_sys_clone+0xce/0x120 kernel/fork.c:2746
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fae54f853d3
RSP: 002b:00007ffc3978c7b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fae54f853d3
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 000055558f3967d0 R11: 0000000000000246 R12: 0000000000000000
R13: 000055558f3a9590 R14: 00000000000d28bd R15: 00007ffc3978c950
 </TASK>
task:kworker/u8:3    state:R  running task     stack:22760 pid:49    tgid:49    ppid:2      task_flags:0x4208160 flags:0x00004000
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6961
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7288
 irqentry_exit+0x36/0x90 kernel/entry/common.c:197
 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0xa/0x20 kernel/kcov.c:314
Code: 00 00 00 e9 58 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 89 f2 <89> fe bf 05 00 00 00 e9 2a fe ff ff 66 2e 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc90000b97ab0 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffff888028148aa8 RCX: ffffffff8b5a41a0
RDX: 0000000000000001 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000001 R08: ca3e19bf206f8e2e R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff88807811cd80 R14: 0000000000000155 R15: ffff88802bdfde00
 rcu_read_lock include/linux/rcupdate.h:842 [inline]
 batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:762 [inline]
 batadv_iv_ogm_schedule_buff+0x5e0/0x14c0 net/batman-adv/bat_iv_ogm.c:834
 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:874 [inline]
 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:867 [inline]
 batadv_iv_send_outstanding_bat_ogm_packet+0x329/0x920 net/batman-adv/bat_iv_ogm.c:1714
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3236
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c5/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g51729 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=70424
rcu: rcu_preempt kthread starved for 10502 jiffies! g51729 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27560 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:7058
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2285
 kthread+0x3c5/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d7/0x6f0 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 15 Comm: ksoftirqd/0 Not tainted 6.16.0-syzkaller-11364-g3c4a063b1f8a #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:__sanitizer_cov_trace_pc+0x66/0x70 kernel/kcov.c:235
Code: 82 18 16 00 00 83 f8 02 75 20 48 8b 8a 20 16 00 00 8b 92 1c 16 00 00 48 8b 01 48 83 c0 01 48 39 d0 73 07 48 89 01 48 89 34 c1 <c3> cc cc cc cc 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000007e10 EFLAGS: 00000006
RAX: 0000000000010102 RBX: ffff8880b8427d80 RCX: ffffffff81a845bf
RDX: ffff88801e2d4880 RSI: ffffffff81a84376 RDI: 0000000000000001
RBP: ffff888063e1b340 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffff9b09b970 R12: 0000000000000001
R13: 0000000000000000 R14: ffff888063e1b340 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8881246c8000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31110ff8 CR3: 0000000050210000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 enqueue_hrtimer+0x96/0x3b0 kernel/time/hrtimer.c:1089
 __run_hrtimer kernel/time/hrtimer.c:1778 [inline]
 __hrtimer_run_queues+0x8ff/0xad0 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x3f0 arch/x86/kernel/apic/apic.c:1056
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 96 a1 02 f6 48 89 df e8 7e f5 02 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 <bf> 01 00 00 00 e8 85 f2 f2 f5 65 8b 05 2e 61 40 08 85 c0 74 16 5b
RSP: 0018:ffffc90000147a48 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffffffff9b0eee90 RCX: ffffffff81c36a2f
RDX: 0000000000000000 RSI: ffffffff8de4c8bd RDI: ffffffff8c15fb80
RBP: 0000000000000286 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff90aad397 R11: 0000000000000000 R12: dffffc0000000000
R13: 000000000000001a R14: 000000000000001a R15: ffff888079b57600
 __debug_check_no_obj_freed lib/debugobjects.c:1108 [inline]
 debug_check_no_obj_freed+0x31f/0x600 lib/debugobjects.c:1129
 slab_free_hook mm/slub.c:2348 [inline]
 slab_free mm/slub.c:4680 [inline]
 kfree+0x28f/0x4d0 mm/slub.c:4879
 slab_free_after_rcu_debug+0x60/0x340 mm/slub.c:4717
 rcu_do_batch kernel/rcu/tree.c:2605 [inline]
 rcu_core+0x79c/0x1530 kernel/rcu/tree.c:2861
 handle_softirqs+0x216/0x8e0 kernel/softirq.c:579
 run_ksoftirqd kernel/softirq.c:968 [inline]
 run_ksoftirqd+0x3a/0x60 kernel/softirq.c:960
 smpboot_thread_fn+0x3f7/0xae0 kernel/smpboot.c:160
 kthread+0x3c5/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/08/04 03:03 upstream 3c4a063b1f8a 7368264b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in handle_softirqs
2025/06/26 11:37 upstream ee88bddf7f2f 26d77996 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in handle_softirqs
2025/06/16 08:36 upstream 08215f5486ec 5f4b362d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in handle_softirqs
2025/06/04 16:59 upstream 5abc7438f1e9 fd5e6e61 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in handle_softirqs
2025/03/28 15:41 upstream acb4f33713b9 49900278 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in handle_softirqs
2025/04/13 07:01 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 2fe2b96c3818 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: soft lockup in handle_softirqs
* Struck through repros no longer work on HEAD.