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INFO: rcu detected stall in sys_munmap

Status: auto-obsoleted due to no activity on 2023/11/06 05:09
Subsystems: kasan mm
[Documentation on labels]
First crash: 781d, last: 781d
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 INFO: rcu detected stall in sys_munmap 1 4 22d 106d 0/2 upstream: reported on 2025/07/12 12:20
linux-5.15 INFO: rcu detected stall in sys_munmap 1 1 102d 102d 0/3 auto-obsoleted due to no activity on 2025/10/24 12:55
linux-6.1 INFO: rcu detected stall in sys_munmap (2) 1 10 6d00h 208d 0/3 upstream: reported on 2025/04/02 07:15
upstream INFO: rcu detected stall in sys_munmap (2) mm 1 syz error 26 46d 66d 0/29 upstream: reported syz repro on 2025/08/22 04:15
linux-6.1 INFO: rcu detected stall in sys_munmap 1 1 461d 461d 0/3 auto-obsoleted due to no activity on 2024/10/31 01:03

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=12e4/1/0x4000000000000000 softirq=47635/47638 fqs=0
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5138/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=69709, q=135 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 14364 Comm: syz-executor.3 Not tainted 6.5.0-next-20230907-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
RIP: 0010:check_kcov_mode kernel/kcov.c:173 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0xb/0x70 kernel/kcov.c:207
Code: 0f 1e fa 48 8b be b0 01 00 00 e8 b0 ff ff ff 31 c0 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 65 8b 05 1d d2 7b 7e <89> c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b 14 25 c0 bc 03 00 a9
RSP: 0018:ffffc900001f0e38 EFLAGS: 00000002
RAX: 0000000000010000 RBX: ffff8880b992ba40 RCX: ffffffff8176d9b3
RDX: ffff88802b678000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000800 R12: ffff8880b992b940
R13: 0000000000000001 R14: ffff888037a20340 R15: ffffffff88655fa0
FS:  00007f51713bc6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f12dd998000 CR3: 000000007a20b000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x5f9/0xc10 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1063 [inline]
 __sysvec_apic_timer_interrupt+0x105/0x3f0 arch/x86/kernel/apic/apic.c:1080
 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1074
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:get_current arch/x86/include/asm/current.h:41 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x17/0x70 kernel/kcov.c:206
Code: ff ff ff 31 c0 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 65 8b 05 1d d2 7b 7e 89 c1 48 8b 34 24 81 e1 00 01 00 00 <65> 48 8b 14 25 c0 bc 03 00 a9 00 01 ff 00 74 0e 85 c9 74 35 8b 82
RSP: 0018:ffffc90016337388 EFLAGS: 00000246
RAX: 0000000080000000 RBX: ffffc900163373b8 RCX: 0000000000000000
RDX: ffff88802b678000 RSI: ffffffff813a5134 RDI: 0000000000000005
RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: ffff8880749b120c R12: ffffc900163373b8
R13: ffffffff81758aa0 R14: ffffc90016337478 R15: ffff88802b678000
 unwind_get_return_address+0x54/0xe0 arch/x86/kernel/unwind_orc.c:369
 arch_stack_walk+0xbe/0x170 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x96/0xd0 kernel/stacktrace.c:122
 kasan_save_stack+0x33/0x50 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 __kasan_slab_alloc+0x81/0x90 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:188 [inline]
 slab_post_alloc_hook mm/slab.h:762 [inline]
 slab_alloc_node mm/slub.c:3478 [inline]
 slab_alloc mm/slub.c:3486 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3493 [inline]
 kmem_cache_alloc+0x172/0x3b0 mm/slub.c:3502
 mt_alloc_one lib/maple_tree.c:160 [inline]
 mas_alloc_nodes+0x182/0x830 lib/maple_tree.c:1249
 mas_node_count_gfp+0x105/0x130 lib/maple_tree.c:1329
 mas_node_count lib/maple_tree.c:1343 [inline]
 mas_wr_node_store+0xb0f/0x18d0 lib/maple_tree.c:3927
 mas_wr_modify lib/maple_tree.c:4213 [inline]
 mas_wr_store_entry.isra.0+0x548/0xe40 lib/maple_tree.c:4253
 mas_store_gfp+0xba/0x190 lib/maple_tree.c:5384
 vma_iter_clear_gfp mm/internal.h:1090 [inline]
 do_vmi_align_munmap+0xc9e/0x15f0 mm/mmap.c:2535
 do_vmi_munmap+0x20e/0x450 mm/mmap.c:2623
 __vm_munmap+0x144/0x390 mm/mmap.c:2908
 __do_sys_munmap mm/mmap.c:2925 [inline]
 __se_sys_munmap mm/mmap.c:2922 [inline]
 __x64_sys_munmap+0x62/0x80 mm/mmap.c:2922
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f517067cb77
Code: 00 00 00 48 c7 c2 b0 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 0b 00 00 00 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:00007f51713bbe98 EFLAGS: 00000246 ORIG_RAX: 000000000000000b
RAX: ffffffffffffffda RBX: 0000000000010000 RCX: 00007f517067cb77
RDX: 0000000000000000 RSI: 0000000000010000 RDI: 00007f5166dff000
RBP: 0000000000000000 R08: 0000000000000000 R09: 00000000000002ab
R10: 0000000020000502 R11: 0000000000000246 R12: 0000000000000003
R13: 00007f51713bbf3c R14: 00007f51713bbf40 R15: 00007f5166dff000
 </TASK>
task:kworker/1:5     state:R  running task     stack:21392 pid:5138  ppid:2      flags:0x00004000
Workqueue: events_power_efficient gc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0xee1/0x59f0 kernel/sched/core.c:6695
 preempt_schedule_irq+0x52/0x90 kernel/sched/core.c:7007
 irqentry_exit+0x35/0x80 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:__seqprop_spinlock_sequence include/linux/seqlock.h:275 [inline]
RIP: 0010:nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:339 [inline]
RIP: 0010:gc_worker+0x2e3/0x17f0 net/netfilter/nf_conntrack_core.c:1490
Code: 00 00 48 c7 c7 08 c0 ce 8e e8 39 a9 f3 f8 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 a7 ee 12 f9 48 85 db 58 0f 85 a4 10 00 00 <e8> 08 f3 12 f9 eb 07 e8 01 f3 12 f9 f3 90 44 8b 35 58 c8 59 06 31
RSP: 0018:ffffc90004587bf8 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff88807790d940 RSI: ffffffff88750373 RDI: 0000000000000007
RBP: ffff888025a00000 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 00000000000362e5
R13: dffffc0000000000 R14: 000000000006c5c9 R15: 0000000000040000
 process_one_work+0x887/0x15d0 kernel/workqueue.c:2630
 process_scheduled_works kernel/workqueue.c:2703 [inline]
 worker_thread+0x8bb/0x1290 kernel/workqueue.c:2784
 kthread+0x33a/0x430 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
 </TASK>
rcu: rcu_preempt kthread starved for 10502 jiffies! g69709 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:29056 pid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0xee1/0x59f0 kernel/sched/core.c:6695
 schedule+0xe7/0x1b0 kernel/sched/core.c:6771
 schedule_timeout+0x157/0x2c0 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x1ec/0xa50 kernel/rcu/tree.c:1613
 rcu_gp_kthread+0x249/0x380 kernel/rcu/tree.c:1812
 kthread+0x33a/0x430 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 12 Comm: kworker/u4:1 Not tainted 6.5.0-next-20230907-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:300 [inline]
RIP: 0010:smp_call_function_many_cond+0x4d6/0x1570 kernel/smp.c:844
Code: 0b 00 85 ed 74 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 fc 4c 89 fd 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 0c 8f 0b 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 3c 0e 00 00 8b 43 08 31
RSP: 0018:ffffc90000117928 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b9941a60 RCX: 0000000000000000
RDX: ffff888016e45940 RSI: ffffffff817c5b94 RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffed101732834d
R13: 0000000000000001 R14: ffff8880b983d8c0 R15: ffff8880b9941a68
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555570d88f8 CR3: 000000000c976000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1012
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:1990 [inline]
 text_poke_bp_batch+0x2ce/0x960 arch/x86/kernel/alternative.c:2200
 text_poke_flush arch/x86/kernel/alternative.c:2391 [inline]
 text_poke_flush arch/x86/kernel/alternative.c:2388 [inline]
 text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2398
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 jump_label_update+0x32e/0x410 kernel/jump_label.c:829
 static_key_enable_cpuslocked+0x1b5/0x270 kernel/jump_label.c:205
 static_key_enable+0x1a/0x20 kernel/jump_label.c:218
 toggle_allocation_gate mm/kfence/core.c:830 [inline]
 toggle_allocation_gate+0xf4/0x250 mm/kfence/core.c:822
 process_one_work+0x887/0x15d0 kernel/workqueue.c:2630
 process_scheduled_works kernel/workqueue.c:2703 [inline]
 worker_thread+0x8bb/0x1290 kernel/workqueue.c:2784
 kthread+0x33a/0x430 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/09/07 05:04 linux-next cd04b2fab5ee 72324844 .config console log report info ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in sys_munmap
* Struck through repros no longer work on HEAD.