INFO: rcu detected stall in sys_close_range

Status: upstream: reported C repro on 2025/08/13 16:29
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+793af646fd66df0b254e@syzkaller.appspotmail.com
First crash: 347d, last: 22d
Bug presence (2)
Date Name Commit Repro Result
2025/12/22 linux-6.6.y (ToT) 5fa4793a2d2d C [report] INFO: rcu detected stall in smp_call_function
2025/12/22 upstream (ToT) 9448598b22c5 C Didn't crash
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in close_range fs 1 1 459d 459d 0/29 auto-obsoleted due to no activity on 2025/07/22 12:43
linux-6.1 INFO: rcu detected stall in sys_close_range (2) origin:lts-only 1 C error 6 8d09h 165d 0/3 upstream: reported C repro on 2026/02/10 20:38
linux-5.15 INFO: rcu detected stall in sys_close_range (2) origin:lts-only 1 syz 1 19d 19d 0/3 upstream: reported syz repro on 2026/07/06 21:37
linux-6.1 INFO: rcu detected stall in sys_close_range 1 C done 3 316d 510d 0/3 auto-obsoleted due to no activity on 2025/12/22 06:21
linux-5.15 INFO: rcu detected stall in sys_close_range 1 syz error 3 192d 266d 0/3 auto-obsoleted due to no activity on 2026/07/02 02:05
Fix bisection attempts (2)
Created Duration User Patch Repo Result
2026/01/04 23:24 2h33m fix candidate upstream OK (0) job log
2025/11/19 15:50 2h26m (2) fix candidate upstream OK (0) job log

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (10412 ticks this GP) idle=e5bc/1/0x4000000000000000 softirq=14897/14898 fqs=3993
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:  1159634          0            0
rcu: 	cputime:    17826      34653           36   ==> 52480(ms)
rcu: 	(t=10500 jiffies g=13289 q=1021 ncpus=2)
CPU: 1 PID: 6244 Comm: syz.0.318 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xc0/0x120 kernel/locking/spinlock.c:194
Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 9b 1d c7 f6 65 8b 05 6c 6c 6e 75 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc900001f0380 EFLAGS: 00000206
RAX: dffffc0000000004 RBX: 0000000000000a02 RCX: 0d1d0ff73f433000
RDX: dffffc0000000000 RSI: ffffffff8acacb60 RDI: 0000000000000001
RBP: ffffc900001f0410 R08: ffffffff911e75ff R09: 1ffffffff223cebf
R10: dffffc0000000000 R11: fffffbfff223cec0 R12: dffffc0000000000
R13: ffff88807aba86b8 R14: ffff88807aba86b8 R15: 1ffff9200003e070
FS:  0000555587eb8500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000021fdf CR3: 00000000268de000 CR4: 00000000003506e0
Call Trace:
 <IRQ>
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 wiphy_work_queue+0x133/0x180 net/wireless/core.c:1639
 __ieee80211_queue_skb_to_iface net/mac80211/rx.c:232 [inline]
 ieee80211_queue_skb_to_iface net/mac80211/rx.c:243 [inline]
 ieee80211_rx_h_mgmt+0x4f0/0x6e0 net/mac80211/rx.c:3994
 ieee80211_rx_handlers+0x65b6/0xb450 net/mac80211/rx.c:4152
 ieee80211_invoke_rx_handlers net/mac80211/rx.c:4182 [inline]
 ieee80211_prepare_and_rx_handle+0x27de/0x6080 net/mac80211/rx.c:5040
 ieee80211_rx_for_interface net/mac80211/rx.c:5125 [inline]
 __ieee80211_rx_handle_packet net/mac80211/rx.c:5298 [inline]
 ieee80211_rx_list+0x28d4/0x3240 net/mac80211/rx.c:5437
 ieee80211_rx_napi+0x1ae/0x3c0 net/mac80211/rx.c:5460
 ieee80211_rx include/net/mac80211.h:4971 [inline]
 ieee80211_handle_queued_frames+0x105/0x190 net/mac80211/main.c:319
 tasklet_action_common+0x2d4/0x460 kernel/softirq.c:809
 handle_softirqs+0x27d/0x820 kernel/softirq.c:578
 __do_softirq kernel/softirq.c:612 [inline]
 invoke_softirq kernel/softirq.c:452 [inline]
 __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:preempt_schedule_irq+0xba/0x150 kernel/sched/core.c:7010
Code: 00 00 43 c6 44 37 04 f8 74 0b 0f 0b 48 f7 03 08 00 00 00 74 6f bf 01 00 00 00 e8 51 81 c8 f6 e8 8c 6d f9 f6 fb bf 01 00 00 00 <e8> 31 b4 ff ff 43 c6 44 37 08 00 48 c7 44 24 40 00 00 00 00 9c 8f
RSP: 0018:ffffc9000b91f7c0 EFLAGS: 00000282
RAX: 0d1d0ff73f433000 RBX: 0000000000000000 RCX: 0d1d0ff73f433000
RDX: dffffc0000000000 RSI: ffffffff8acacb60 RDI: 0000000000000001
RBP: ffffc9000b91f870 R08: ffffffff8e8c6e6f R09: 1ffffffff1d18dcd
R10: dffffc0000000000 R11: fffffbfff1d18dce R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92001723ef8
 irqentry_exit+0x67/0x70 kernel/entry/common.c:438
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:678
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:245 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x10/0x90 kernel/kcov.c:313
Code: 11 10 48 89 74 11 18 48 89 44 11 20 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 48 8b 04 24 65 48 8b 15 30 cf 7c 7e <65> 8b 0d 31 cf 7c 7e 81 e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75
RSP: 0018:ffffc9000b91f938 EFLAGS: 00000246
RAX: ffffffff813b2298 RBX: ffffc9000b91f9b0 RCX: 0000000000000000
RDX: ffff888029fb0000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000001 R08: ffff888029fb0000 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000000 R12: ffffffff81eef10d
R13: ffff888029fb0000 R14: dffffc0000000000 R15: 1ffff92001723f36
 unwind_get_return_address+0x68/0xc0 arch/x86/kernel/unwind_orc.c:369
 arch_stack_walk+0x11d/0x190 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122
 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46
 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492
 task_work_add+0xdd/0x470 kernel/task_work.c:82
 fput+0xdd/0x1a0 fs/file_table.c:440
 filp_close+0x10f/0x150 fs/open.c:1547
 __range_close fs/file.c:698 [inline]
 __close_range+0x379/0x690 fs/file.c:755
 __do_sys_close_range fs/open.c:1599 [inline]
 __se_sys_close_range fs/open.c:1596 [inline]
 __x64_sys_close_range+0x7a/0x90 fs/open.c:1596
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f7751f9de59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffddad467f8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: ffffffffffffffda RBX: 00007ffddad468e0 RCX: 00007f7751f9de59
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 0000000000021fdf R08: 0000000000000001 R09: 0000000000000000
R10: 0000001b2cb20000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7752225fac R14: 00007f7752225fa8 R15: 00007f7752225fa0
 </TASK>

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/04 12:35 linux-6.6.y d1cfde2d5d15 fcece630 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_close_range
2026/06/26 06:13 linux-6.6.y d1cfde2d5d15 7ff32d8b .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_close_range
2026/05/27 06:44 linux-6.6.y 0a40c6fbd105 2b01f00e .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_close_range
2026/05/01 14:16 linux-6.6.y 258cf62a6dfd 753c55b9 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_close_range
2026/04/07 05:23 linux-6.6.y 80de0a958133 4440e7c2 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_close_range
2026/03/25 02:17 linux-6.6.y 4fc00fe35d46 74e70d19 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_close_range
2026/02/05 06:43 linux-6.6.y 2cf6f68313dc ea10c935 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_close_range
2025/12/22 09:05 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_close_range
2025/08/13 16:29 linux-6.6.y 3a8ababb8b6a 22ec1469 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_close_range
* Struck through repros no longer work on HEAD.