syzbot


INFO: rcu detected stall in dput (2)

Status: upstream: reported on 2024/05/28 13:43
Reported-by: syzbot+883c06f8852b37453ea8@syzkaller.appspotmail.com
First crash: 407d, last: 13d
Similar bugs (12)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in dput (4) kvm 1 C error error 2 1308d 1667d 0/29 closed as invalid on 2022/02/08 10:37
linux-5.15 INFO: rcu detected stall in dput (3) 1 13 14d 212d 0/3 upstream: reported on 2024/12/09 17:03
upstream INFO: rcu detected stall in dput (3) kernel 1 1 2010d 2009d 0/29 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in dput (8) mm 1 C done 398 5h55m 556d 0/29 upstream: reported C repro on 2023/12/31 19:35
linux-5.15 INFO: rcu detected stall in dput 1 2 680d 720d 0/3 auto-obsoleted due to no activity on 2023/12/08 00:28
upstream INFO: rcu detected stall in dput (6) fs 1 2 981d 1041d 0/29 auto-obsoleted due to no activity on 2023/01/16 04:13
linux-5.15 INFO: rcu detected stall in dput (2) 1 10 340d 481d 0/3 auto-obsoleted due to no activity on 2024/11/12 09:55
upstream INFO: rcu detected stall in dput (5) fs 1 1 1177d 1177d 0/29 auto-closed as invalid on 2022/07/18 12:41
linux-6.1 INFO: rcu detected stall in dput 1 1 728d 728d 0/3 auto-obsoleted due to no activity on 2023/10/20 22:44
upstream INFO: rcu detected stall in dput fs 1 1 2045d 2045d 0/29 closed as invalid on 2019/12/04 14:04
linux-6.6 INFO: rcu detected stall in dput 1 4 1d00h 22d 0/2 upstream: reported on 2025/06/17 20:59
upstream INFO: rcu detected stall in dput (2) kernel 1 2 2010d 2010d 0/29 closed as invalid on 2020/01/08 05:33

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P8362/1:b..l
	(detected by 1, t=10503 jiffies, g=32497, q=79 ncpus=2)
task:syz.1.1075      state:R  running task     stack:25728 pid:8362  ppid:4254   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
 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:bytes_is_nonzero mm/kasan/generic.c:87 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x81/0x290 mm/kasan/generic.c:189
Code: 03 4e 8d 14 3b 4d 89 d6 4d 29 ce 49 83 fe 10 7f 26 4d 85 f6 0f 84 39 01 00 00 48 f7 d3 4c 01 db 41 80 39 00 0f 85 c1 01 00 00 <49> ff c1 48 ff c3 75 ee e9 1c 01 00 00 44 89 cb 83 e3 07 0f 84 b5
RSP: 0018:ffffc90003516f20 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffffffffffffff RCX: ffffffff81dad774
RDX: 0000000000000001 RSI: 0000000000000080 RDI: ffffc90003516fa0
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff520006a2e03
R10: fffff520006a2e04 R11: 1ffff920006a2df4 R12: dffffc0000000000
R13: 1ffff920006a2df0 R14: 0000000000000010 R15: dffffc0000000001
 memset+0x1e/0x40 mm/kasan/shadow.c:44
 save_stack+0xc4/0x1e0 mm/page_owner.c:111
 __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:1459 [inline]
 free_pcp_prepare mm/page_alloc.c:1509 [inline]
 free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384
 free_unref_page_list+0xbb/0x8e0 mm/page_alloc.c:3525
 release_pages+0x1f92/0x2200 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+0x75b/0x2050 mm/shmem.c:946
 shmem_truncate_range mm/shmem.c:1062 [inline]
 shmem_evict_inode+0x248/0xa40 mm/shmem.c:1171
 evict+0x485/0x870 fs/inode.c:705
 __dentry_kill+0x431/0x650 fs/dcache.c:611
 dentry_kill+0xb8/0x290 fs/dcache.c:-1
 dput+0xfa/0x1d0 fs/dcache.c:918
 __fput+0x5e0/0x920 fs/file_table.c:328
 task_work_run+0x1ca/0x250 kernel/task_work.c:203
 exit_task_work include/linux/task_work.h:39 [inline]
 do_exit+0x936/0x2400 kernel/exit.c:871
 do_group_exit+0x217/0x2d0 kernel/exit.c:1021
 get_signal+0x1272/0x1350 kernel/signal.c:2871
 arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f9bda78e929
RSP: 002b:00007f9bdb6e4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: 0000000000000007 RBX: 00007f9bda9b5fa0 RCX: 00007f9bda78e929
RDX: 0000000000000010 RSI: 0000200000000080 RDI: 0000000000000011
RBP: 00007f9bda810b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f9bda9b5fa0 R15: 00007ffc6ee42dd8
 </TASK>
rcu: rcu_preempt kthread starved for 10553 jiffies! g32497 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:27040 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6730
 preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6754
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0xf6/0x100 kernel/locking/spinlock.c:194
 debug_object_free+0x29a/0x3e0 lib/debugobjects.c:855
 destroy_timer_on_stack kernel/time/timer.c:812 [inline]
 schedule_timeout+0x173/0x280 kernel/time/timer.c:1969
 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x95/0x380 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 8382 Comm: syz.3.1079 Not tainted 6.1.141-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:lockdep_hardirqs_on+0xa6/0x140 kernel/locking/lockdep.c:4379
Code: 48 3b 83 d0 0a 00 00 75 76 49 89 fe 48 c7 c7 e0 ff 6b 8a e8 0c 15 00 00 65 c7 05 91 e4 f2 75 01 00 00 00 4c 89 b3 80 0a 00 00 <8b> 83 78 0a 00 00 ff c0 89 83 78 0a 00 00 89 83 90 0a 00 00 65 48
RSP: 0018:ffffc900035d7be0 EFLAGS: 00000086
RAX: 0000000000000000 RBX: ffff88807d045940 RCX: 22beef320c712d00
RDX: dffffc0000000000 RSI: ffffffff8a6bffe0 RDI: ffffffff8abf1360
RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffed1027fecf81
R10: ffffed1027fecf81 R11: 1ffff11027fecf80 R12: 0000000000000000
R13: 0000000000000000 R14: ffffffff8a200e86 R15: 0000000000000000
FS:  00007fcb906136c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fcb8f9b6088 CR3: 000000001f3c0000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline]
RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline]
RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:147 [inline]
RIP: 0010:wrmsr arch/x86/include/asm/msr.h:254 [inline]
RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:206
Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 4f 99 f8 02 66 2e 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc900035d7cb0 EFLAGS: 00000246
RAX: 00000000000000f6 RBX: ffffffff8c3d0b78 RCX: 000000000000083f
RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000083f
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff520006baf85
R10: fffff520006baf85 R11: 1ffff920006baf84 R12: ffff8880b8e33e01
R13: dffffc0000000000 R14: dffffc0000000000 R15: 0000000000000020
 arch_irq_work_raise+0x82/0xd0 arch/x86/kernel/irq_work.c:31
 irq_work_queue+0x95/0x140 kernel/irq_work.c:114
 bpf_send_signal_common+0x2b2/0x420 kernel/trace/bpf_trace.c:879
 ____bpf_send_signal kernel/trace/bpf_trace.c:888 [inline]
 bpf_send_signal+0x15/0x20 kernel/trace/bpf_trace.c:886
 bpf_prog_7ba5217f62dcd359+0x38/0x3c
 bpf_dispatcher_nop_func include/linux/bpf.h:1001 [inline]
 __bpf_prog_run include/linux/filter.h:603 [inline]
 bpf_prog_run include/linux/filter.h:610 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2285 [inline]
 bpf_trace_run2+0x1cd/0x3b0 kernel/trace/bpf_trace.c:2324
 __bpf_trace_sys_enter+0x60/0x70 include/trace/events/syscalls.h:18
 trace_sys_enter+0x6b/0x80 include/trace/events/syscalls.h:18
 syscall_trace_enter+0xf0/0x150 kernel/entry/common.c:81
 do_syscall_64+0x24/0xa0 arch/x86/entry/common.c:77
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fcb8f72ab19
Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 04 25
RSP: 002b:00007fcb90612b40 EFLAGS: 00000246 ORIG_RAX: 000000000000000f
RAX: ffffffffffffffda RBX: 00007fcb8f9b6088 RCX: 00007fcb8f72ab19
RDX: 00007fcb90612b40 RSI: 00007fcb90612c70 RDI: 0000000000000011
RBP: 00007fcb8f9b6080 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fcb8f9b608c
R13: 0000000000000000 R14: 00007ffc30d691e0 R15: 00007ffc30d692c8
 </TASK>

Crashes (37):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/27 03:20 linux-6.1.y 58485ff1a74f 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/06/15 01:13 linux-6.1.y 58485ff1a74f 5f4b362d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/06/10 16:12 linux-6.1.y 58485ff1a74f 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/06/06 03:38 linux-6.1.y 58485ff1a74f 6b6b5f21 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/06/01 22:49 linux-6.1.y da3c5173c55f 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/06/01 04:59 linux-6.1.y da3c5173c55f 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/05/25 05:54 linux-6.1.y da3c5173c55f ed351ea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/05/22 05:34 linux-6.1.y 325285d9fc86 0919b50b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/05/02 23:01 linux-6.1.y b6736e03756f b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/05/01 09:28 linux-6.1.y 535ec20c5027 ce7952f4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/04/14 20:59 linux-6.1.y 420102835862 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/03/27 02:45 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 dput
2025/03/24 03:31 linux-6.1.y 344a09659766 875573af .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/03/23 14:12 linux-6.1.y 344a09659766 4e8d3850 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/03/16 14:30 linux-6.1.y 344a09659766 e2826670 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/03/07 16:28 linux-6.1.y 3a8358583626 7e3bd60d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/02/07 02:28 linux-6.1.y 0cbb5f65e52f 8002dd28 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/01/07 02:32 linux-6.1.y 7dc732d24ff7 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/01/05 15:00 linux-6.1.y 7dc732d24ff7 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2024/11/29 03:05 linux-6.1.y e4d90d63d385 5df23865 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2024/11/28 02:50 linux-6.1.y e4d90d63d385 5df23865 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2024/11/03 13:45 linux-6.1.y 7c15117f9468 f00eed24 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2024/10/07 11:23 linux-6.1.y aa4cd140bba5 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2024/09/14 02:18 linux-6.1.y 5f55cad62cc9 b58f933c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2024/08/21 21:13 linux-6.1.y ee5e09825b81 db5852f9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2024/07/20 14:02 linux-6.1.y 9b3f9a5b12dc b88348e9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2024/07/20 00:30 linux-6.1.y 9b3f9a5b12dc 890ce4f3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2024/07/19 16:53 linux-6.1.y 9b3f9a5b12dc 890ce4f3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2024/07/10 17:38 linux-6.1.y 7753af06eebf 6f7fa383 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2024/06/22 00:53 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2024/06/21 21:40 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2024/06/08 10:13 linux-6.1.y 88690811da69 82c05ab8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2024/06/08 08:48 linux-6.1.y 88690811da69 82c05ab8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2024/06/07 10:21 linux-6.1.y 88690811da69 121701b6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2024/06/03 06:34 linux-6.1.y 88690811da69 3113787f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2024/06/03 00:53 linux-6.1.y 88690811da69 3113787f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2024/05/28 13:42 linux-6.1.y 88690811da69 f550015e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
* Struck through repros no longer work on HEAD.