INFO: rcu detected stall in inet_ioctl

Status: upstream: reported on 2026/05/26 00:31
Reported-by: syzbot+24f81a96894a6c85df30@syzkaller.appspotmail.com
First crash: 83d, last: 15d
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in inet_ioctl (3) prio:low mm 1 1 162d 162d 0/29 auto-obsoleted due to no activity on 2026/06/05 17:53
upstream INFO: rcu detected stall in inet_ioctl net 1 1 2635d 2635d 0/29 auto-closed as invalid on 2019/10/25 09:21
upstream INFO: rcu detected stall in inet_ioctl (2) mm 1 1 689d 689d 0/29 auto-obsoleted due to no activity on 2024/12/25 20:16
linux-6.6 INFO: rcu detected stall in inet_ioctl 1 1 51d 51d 0/2 upstream: reported on 2026/06/26 19:25

Sample crash report:
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-.... } 2641 jiffies s: 134873 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: 26760 Comm: syz.2.6024 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:check_preemption_disabled+0x42/0x110 lib/smp_processor_id.c:55
Code: 65 8b 05 91 ec d1 75 65 8b 0d 32 42 d2 75 f7 c1 ff ff ff 7f 74 1f 65 48 8b 0c 25 28 00 00 00 48 3b 4c 24 08 0f 85 c4 00 00 00 <48> 83 c4 10 5b 41 5e 41 5f 5d c3 48 c7 04 24 00 00 00 00 9c 8f 04
RSP: 0018:ffffc900001e0088 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 921cdf08025a4900
RDX: 0000000000000000 RSI: ffffffff8adf5dc0 RDI: ffffffff8adf5d80
RBP: ffffc900001e01e8 R08: ffffffff8e210aef R09: 1ffffffff1c4215d
R10: dffffc0000000000 R11: fffffbfff1c4215e R12: 0000000000000001
R13: 1ffff9200003c028 R14: 0000000000000000 R15: dffffc0000000000
FS:  00007f94ea4e16c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f952bbbcb4c CR3: 0000000075d4d000 CR4: 00000000003506e0
DR0: 0000200000000300 DR1: 0000200000000200 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline]
 rcu_is_watching+0x11/0xa0 kernel/rcu/tree.c:721
 trace_lock_acquire include/trace/events/lock.h:24 [inline]
 lock_acquire+0xe3/0x4a0 kernel/locking/lockdep.c:5647
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock_sched include/linux/rcupdate.h:883 [inline]
 pfn_valid include/linux/mmzone.h:1857 [inline]
 __virt_addr_valid+0x1a5/0x540 arch/x86/mm/physaddr.c:65
 kasan_addr_to_slab+0x9/0xc0 mm/kasan/common.c:36
 __kasan_record_aux_stack+0xf/0xc0 mm/kasan/generic.c:471
 irq_work_queue_on+0x10f/0x260 kernel/irq_work.c:140
 rcu_read_unlock_special+0x3c9/0x510 kernel/rcu/tree_plugin.h:678
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 __perf_event_output kernel/events/core.c:7741 [inline]
 perf_event_output_forward+0x271/0x2f0 kernel/events/core.c:7750
 __perf_event_overflow+0x457/0x630 kernel/events/core.c:9496
 perf_swevent_overflow kernel/events/core.c:9579 [inline]
 perf_swevent_event+0x315/0x570 kernel/events/core.c:9630
 perf_tp_event+0x36b/0xc10 kernel/events/core.c:10064
 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10032
 perf_trace_preemptirq_template+0x268/0x320 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+0x7f/0x510 kernel/rcu/tree_plugin.h:685
Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 a2 7c 95 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc900001e0ae0 EFLAGS: 00000206
RAX: 921cdf08025a4900 RBX: 1ffff9200003c164 RCX: 921cdf08025a4900
RDX: dffffc0000000000 RSI: ffffffff8a8c17a0 RDI: ffffffff8adf5de0
RBP: ffffc900001e0bd0 R08: ffffffff90b1024f R09: 1ffffffff2162049
R10: dffffc0000000000 R11: fffffbfff216204a R12: 0000000000000246
R13: dffffc0000000000 R14: ffff8880b8f3bb00 R15: 0000000000000002
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 ieee80211_iterate_active_interfaces_atomic+0x156/0x170 net/mac80211/util.c:826
 mac80211_hwsim_beacon+0xb7/0x1b0 drivers/net/wireless/mac80211_hwsim.c:2147
 __run_hrtimer kernel/time/hrtimer.c:1751 [inline]
 __hrtimer_run_queues+0x522/0xc90 kernel/time/hrtimer.c:1815
 hrtimer_run_softirq+0x173/0x290 kernel/time/hrtimer.c:1832
 handle_softirqs+0x291/0x910 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x13b/0x230 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:finish_task_switch+0x267/0x8e0 kernel/sched/core.c:5125
Code: d6 08 85 c0 0f 84 38 01 00 00 48 85 db 0f 85 57 01 00 00 0f 1f 44 00 00 4c 89 e7 e8 93 b1 e0 08 e8 2e 11 2f 00 fb 4c 8b 65 b8 <49> 8d bc 24 f8 15 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0
RSP: 0018:ffffc9000498f140 EFLAGS: 00000286
RAX: 921cdf08025a4900 RBX: 0000000000000000 RCX: 921cdf08025a4900
RDX: dffffc0000000000 RSI: ffffffff8a8c17a0 RDI: ffffffff8adf5de0
RBP: ffffc9000498f190 R08: ffffffff90b1024f R09: 1ffffffff2162049
R10: dffffc0000000000 R11: fffffbfff216204a R12: ffff8880709e5a00
R13: 1ffff110171e76fa R14: dffffc0000000000 R15: ffff8880b8f3b7d0
 context_switch kernel/sched/core.c:5249 [inline]
 __schedule+0x1087/0x4030 kernel/sched/core.c:6563
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6732
 preempt_schedule+0xbc/0xd0 kernel/sched/core.c:6756
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 unwind_next_frame+0x172b/0x1fd0 arch/x86/kernel/unwind_orc.c:629
 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 __kasan_slab_alloc+0x6b/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x4b/0x490 mm/slab.h:737
 slab_alloc_node mm/slub.c:3359 [inline]
 kmem_cache_alloc_node+0x1ad/0x310 mm/slub.c:3404
 __alloc_skb+0xf9/0x7d0 net/core/skbuff.c:505
 alloc_skb include/linux/skbuff.h:1303 [inline]
 nlmsg_new include/net/netlink.h:998 [inline]
 rtmsg_ifa+0xf9/0x1f0 net/ipv4/devinet.c:1933
 __inet_del_ifa+0x2c8/0x1090 net/ipv4/devinet.c:406
 inet_del_ifa net/ipv4/devinet.c:482 [inline]
 devinet_ioctl+0x954/0x1bf0 net/ipv4/devinet.c:1180
 inet_ioctl+0x2fa/0x460 net/ipv4/af_inet.c:1008
 sock_do_ioctl+0xfb/0x320 net/socket.c:1202
 sock_ioctl+0x48a/0x700 net/socket.c:1321
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856
 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: 0033:0x7f94e959e019
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:00007f94ea4e1028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f94e9825fa0 RCX: 00007f94e959e019
RDX: 0000200000000040 RSI: 0000000000008916 RDI: 000000000000000a
RBP: 00007f94e963500c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f94e9826038 R14: 00007f94e9825fa0 R15: 00007ffdc2fe2af8
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/02 11:00 linux-6.1.y fb28aa725e05 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in inet_ioctl
2026/07/27 13:00 linux-6.1.y dc5c83b7f5f8 aae9036b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in inet_ioctl
2026/05/26 00:30 linux-6.1.y dcbcab9d7079 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in inet_ioctl
* Struck through repros no longer work on HEAD.