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INFO: rcu detected stall in dput (2)

Status: upstream: reported C repro on 2024/05/28 13:43
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+883c06f8852b37453ea8@syzkaller.appspotmail.com
First crash: 577d, last: 5d05h
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2025/12/21 linux-6.1.y (ToT) 50cbba13faa2 C [report] INFO: rcu detected stall in sys_rename
2025/12/21 upstream (ToT) 9094662f6707 C Didn't crash
▶ ▼ 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 1477d 1837d 0/29 closed as invalid on 2022/02/08 10:37
linux-5.15 INFO: rcu detected stall in dput (3) origin:lts-only 1 syz 22 15d 382d 0/3 upstream: reported syz repro on 2024/12/09 17:03
upstream INFO: rcu detected stall in dput (3) mm 1 1 2179d 2179d 0/29 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in dput (8) fs 1 C done 600 6h29m 726d 0/29 upstream: reported C repro on 2023/12/31 19:35
linux-5.15 INFO: rcu detected stall in dput 1 2 849d 889d 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 1151d 1210d 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 509d 650d 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 1347d 1347d 0/29 auto-closed as invalid on 2022/07/18 12:41
linux-6.1 INFO: rcu detected stall in dput 1 1 897d 897d 0/3 auto-obsoleted due to no activity on 2023/10/20 22:44
upstream INFO: rcu detected stall in dput fs 1 1 2214d 2214d 0/29 closed as invalid on 2019/12/04 14:04
linux-6.6 INFO: rcu detected stall in dput 1 42 2d02h 191d 0/2 upstream: reported on 2025/06/17 20:59
upstream INFO: rcu detected stall in dput (2) mm 1 2 2179d 2179d 0/29 closed as invalid on 2020/01/08 05:33

Sample crash report:
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-.... } 2666 jiffies s: 4493 root: 0x2/.
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4378 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x13/0x60 kernel/kcov.c:216
Code: 48 8b 3d 90 30 7e 0c 48 89 de 5b e9 47 68 4f 00 00 00 cc cc 00 00 cc 48 8b 04 24 65 48 8b 0d 64 8f 81 7e 65 8b 15 65 8f 81 7e <81> e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 1c 16 00 00
RSP: 0018:ffffc900001e0788 EFLAGS: 00000097
RAX: ffffffff81a3b400 RBX: 0000000000000001 RCX: ffff8880260f9dc0
RDX: 0000000000000101 RSI: 0000000000000001 RDI: 0000000000000008
RBP: 0000000000000001 R08: dffffc0000000000 R09: ffffed10171e6afa
R10: ffffed10171e6afa R11: 1ffff110171e6af9 R12: ffffffff8c97d7a0
R13: dffffc0000000000 R14: ffffc900001e0840 R15: ffffc900001e0860
FS:  0000555570004500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f20529b42f8 CR3: 000000005c24f000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 perf_swevent_get_recursion_context+0x30/0x150 kernel/events/core.c:9723
 perf_trace_buf_alloc+0x54/0x300 kernel/trace/trace_event_perf.c:414
 perf_trace_preemptirq_template+0x149/0x330 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle+0xd3/0x140 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x24/0x40 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728
RIP: 0010:rcu_read_unlock_special+0x84/0x500 kernel/rcu/tree_plugin.h:685
Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 fd 86 96 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0018:ffffc900001e09c0 EFLAGS: 00000206
RAX: 7c719f5d14206c00 RBX: 1ffff9200003c140 RCX: 7c719f5d14206c00
RDX: dffffc0000000000 RSI: ffffffff8a6c0600 RDI: ffffffff8abef920
RBP: ffffc900001e0ac0 R08: dffffc0000000000 R09: ffffed10171e6afa
R10: ffffed10171e6afa R11: 1ffff110171e6af9 R12: 0000000000000246
R13: dffffc0000000000 R14: ffff8880b8f3b900 R15: 0000000000000002
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 process_backlog+0x3ff/0x6e0 net/core/dev.c:6024
 __napi_poll+0xc0/0x460 net/core/dev.c:6590
 napi_poll net/core/dev.c:6657 [inline]
 net_rx_action+0x5b1/0xad0 net/core/dev.c:6771
 handle_softirqs+0x2a1/0x920 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:679
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:refill_obj_stock+0x481/0x680 mm/memcontrol.c:3346
Code: 0f 85 72 01 00 00 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 1f ab 38 08 f7 c3 00 02 00 00 0f 84 44 ff ff ff fb 4d 85 ed <0f> 85 3f ff ff ff e9 42 ff ff ff e8 5f 41 2c 02 85 c0 0f 84 b5 fc
RSP: 0018:ffffc90003d97b00 EFLAGS: 00000246
RAX: 7c719f5d14206c00 RBX: 0000000000000a02 RCX: 7c719f5d14206c00
RDX: dffffc0000000000 RSI: ffffffff8a6c0600 RDI: ffffffff8abef920
RBP: ffffc90003d97c00 R08: dffffc0000000000 R09: ffffed10171e6afa
R10: ffffed10171e6afa R11: 1ffff110171e6af9 R12: dffffc0000000000
R13: 0000000000000000 R14: 0000000000000000 R15: ffff8880b8f36938
 memcg_slab_free_hook+0x125/0x1f0 mm/slab.h:569
 slab_free mm/slub.c:3682 [inline]
 kmem_cache_free+0xe0/0x290 mm/slub.c:3709
 __dentry_kill+0x4ef/0x650 fs/dcache.c:625
 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
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xee/0x180 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: 0033:0x7f205278e3aa
Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 43 91 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 a3 91 02 00 8b 44 24
RSP: 002b:00007ffec4e93ad0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007f205278e3aa
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007ffec4e93b2c R08: 00007ffec4e9342c R09: 00007ffec4e93837
R10: 00007ffec4e934b0 R11: 0000000000000293 R12: 0000000000000023
R13: 00000000000927c0 R14: 000000000001c023 R15: 00007ffec4e93b80
 </TASK>

Crashes (51):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/21 14:41 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in dput
2025/12/10 12:32 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 dput
2025/12/01 04:55 linux-6.1.y f6e38ae624cf d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/11/05 14:08 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 dput
2025/10/23 20:29 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 dput
2025/10/23 03:02 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 dput
2025/10/22 15:31 linux-6.1.y 8e6e2188d949 252fbbad .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/09/16 07:30 linux-6.1.y 3db754f56897 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/09/15 05:38 linux-6.1.y 3db754f56897 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/09/02 05:34 linux-6.1.y f89b6e15694c 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/08/30 13:05 linux-6.1.y f89b6e15694c 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/07/23 15:29 linux-6.1.y 3369c6df2fae e1dd4f22 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
2025/07/11 05:13 linux-6.1.y dfc486ec9cce 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in dput
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.