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INFO: rcu detected stall in sys_unlink (2)

Status: upstream: reported on 2025/03/27 11:38
Reported-by: syzbot+a0dc8f91386bb1406734@syzkaller.appspotmail.com
First crash: 447d, last: 18d
▶ ▼ Similar bugs (11)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: rcu detected stall in sys_unlink (4) 1 1 441d 441d 0/3 auto-obsoleted due to no activity on 2025/07/10 21:02
linux-5.15 INFO: rcu detected stall in sys_unlink (3) 1 1 591d 591d 0/3 auto-obsoleted due to no activity on 2025/02/11 14:08
upstream INFO: rcu detected stall in sys_unlink (2) kernel 1 2 1241d 1326d 0/29 auto-obsoleted due to no activity on 2023/04/22 20:06
upstream INFO: rcu detected stall in sys_unlink (3) mm 1 C error 389 2h43m 1038d 0/29 upstream: reported C repro on 2023/08/13 23:42
linux-5.15 INFO: rcu detected stall in sys_unlink (5) 1 10 33d 265d 0/3 upstream: reported on 2025/09/25 16:42
linux-6.1 INFO: rcu detected stall in sys_unlink 1 4 657d 876d 0/3 auto-obsoleted due to no activity on 2024/12/07 03:28
linux-5.15 INFO: rcu detected stall in sys_unlink (2) 1 3 710d 721d 0/3 auto-obsoleted due to no activity on 2024/10/15 13:02
linux-6.6 INFO: rcu detected stall in sys_unlink 1 40 12h32m 331d 0/2 upstream: reported on 2025/07/20 18:19
upstream INFO: rcu detected stall in sys_unlink mm kasan 1 1 1417d 1417d 0/29 auto-obsoleted due to no activity on 2022/10/29 07:23
linux-5.15 INFO: rcu detected stall in sys_unlink 1 1 827d 827d 0/3 auto-obsoleted due to no activity on 2024/06/20 14:47
android-5-15 BUG: soft lockup in sys_unlink 1 7 769d 791d 0/2 auto-obsoleted due to no activity on 2024/08/07 01:29

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4973/1:b..l
	(detected by 0, t=10503 jiffies, g=61257, q=65 ncpus=2)
task:syz-executor    state:R  running task     stack:21552 pid:4973  ppid:4972   flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:preempt_count_add+0x2/0x190 kernel/sched/core.c:5701
Code: e1 07 80 c1 03 38 c1 7c 97 48 8b 3c 24 e8 46 97 7a 00 eb 8c e9 f5 fe ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 41 57 <41> 56 53 49 bf 00 00 00 00 00 fc ff df 48 c7 c0 40 41 c0 96 48 c1
RSP: 0018:ffffc900047c72c0 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffc900047c7408 RCX: 0000000000000001
RDX: ffffc900047c7498 RSI: dffffc0000000000 RDI: 0000000000000001
RBP: ffffc900047c7450 R08: ffffc900047c7401 R09: ffffc900047c7408
R10: dffffc0000000000 R11: fffff520008f8e8d R12: ffffffff81394dfe
R13: ffffc900047c73a8 R14: dffffc0000000000 R15: 1ffff920008f8e81
 unwind_next_frame+0xaf/0x20b0 arch/x86/kernel/unwind_orc.c:433
 __unwind_start+0x5bb/0x740 arch/x86/kernel/unwind_orc.c:717
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0xda/0x140 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122
 save_stack+0x121/0x230 mm/page_owner.c:127
 __reset_page_owner+0x51/0x1a0 mm/page_owner.c:148
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1486 [inline]
 free_pcp_prepare mm/page_alloc.c:1536 [inline]
 free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3413
 free_unref_page_list+0xbb/0x8e0 mm/page_alloc.c:3554
 release_pages+0x1fa6/0x2220 mm/swap.c:1035
 __pagevec_release+0x6d/0xe0 mm/swap.c:1055
 pagevec_release include/linux/pagevec.h:71 [inline]
 folio_batch_release include/linux/pagevec.h:135 [inline]
 shmem_undo_range+0x7c2/0x20c0 mm/shmem.c:946
 shmem_truncate_range mm/shmem.c:1062 [inline]
 shmem_evict_inode+0x25b/0xa80 mm/shmem.c:1171
 evict+0x4c9/0x8d0 fs/inode.c:705
 do_unlinkat+0x388/0x580 fs/namei.c:4405
 __do_sys_unlink fs/namei.c:4446 [inline]
 __se_sys_unlink fs/namei.c:4444 [inline]
 __x64_sys_unlink+0x45/0x50 fs/namei.c:4444
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f2f0a79bf47
RSP: 002b:00007ffe1cf41b28 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f2f0a79bf47
RDX: 00007ffe1cf41b50 RSI: 00007ffe1cf41be0 RDI: 00007ffe1cf41be0
RBP: 00007ffe1cf41be0 R08: 00007ffe1cf42be0 R09: 00000000ffffffff
R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffe1cf42c70
R13: 00007f2f0a8321ca R14: 00000000000e3d90 R15: 00007ffe1cf42cb0
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 6951 jiffies! g61257 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=54624
rcu: rcu_preempt kthread starved for 6954 jiffies! g61257 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:27736 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 schedule+0xb9/0x180 kernel/sched/core.c:6638
 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168
 rcu_gp_fqs_loop+0x303/0x1340 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x99/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 1 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:741

Crashes (27):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/30 11:03 linux-6.1.y dcbcab9d7079 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2026/05/21 17:47 linux-6.1.y c27210688955 e195359d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2026/05/10 08:07 linux-6.1.y ad16b162f21d 29233ece .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2026/04/15 23:03 linux-6.1.y 8e8fc038cad5 c441f497 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2026/02/24 20:57 linux-6.1.y 779f9571ac3e 96b1aa46 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2026/02/21 03:34 linux-6.1.y 779f9571ac3e 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2026/02/12 10:28 linux-6.1.y 8ce36b2849ef 76a109e2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2026/02/10 17:51 linux-6.1.y 0182cb5b74ee 91d776d3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2026/02/01 14:55 linux-6.1.y cd9b81672742 6b8752f2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2026/01/31 23:55 linux-6.1.y cd9b81672742 afc0c4d4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2026/01/31 23:53 linux-6.1.y cd9b81672742 afc0c4d4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2026/01/31 23:48 linux-6.1.y cd9b81672742 afc0c4d4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2026/01/27 21:55 linux-6.1.y cd9b81672742 9a514c2f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2026/01/27 21:48 linux-6.1.y cd9b81672742 9a514c2f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2026/01/26 20:41 linux-6.1.y cd9b81672742 a4c52dd6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2025/12/10 18:37 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2025/11/05 11:26 linux-6.1.y f6e38ae624cf a6c9c731 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2025/10/30 12:43 linux-6.1.y f6e38ae624cf fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2025/10/25 09:55 linux-6.1.y 8e6e2188d949 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2025/09/24 01:47 linux-6.1.y 363a599da6d9 e667a34f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2025/09/20 02:49 linux-6.1.y 363a599da6d9 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2025/09/10 06:06 linux-6.1.y f97f1002271b fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2025/09/08 18:04 linux-6.1.y 28c695c365e1 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2025/08/07 20:45 linux-6.1.y 3594f306da12 04cffc22 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2025/05/07 14:34 linux-6.1.y ac7079a42ea5 350f4ffc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_unlink
2025/04/10 09:45 linux-6.1.y 3dfebb87d7eb 988b336c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
2025/03/27 11:38 linux-6.1.y 344a09659766 20510e88 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_unlink
* Struck through repros no longer work on HEAD.