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INFO: rcu detected stall in mac80211_hwsim_beacon (4)

Status: upstream: reported on 2025/09/09 14:58
Reported-by: syzbot+16566e2176db580ec63f@syzkaller.appspotmail.com
First crash: 142d, last: 10d
▶ ▼ Similar bugs (9)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in mac80211_hwsim_beacon kernel 1 C error inconclusive 1904 1374d 1954d 0/29 closed as invalid on 2022/10/12 18:37
linux-6.1 INFO: rcu detected stall in mac80211_hwsim_beacon (3) 1 1 162d 162d 0/3 auto-obsoleted due to no activity on 2025/11/28 14:14
linux-5.15 INFO: rcu detected stall in mac80211_hwsim_beacon 1 1 832d 832d 0/3 auto-obsoleted due to no activity on 2024/01/28 07:17
linux-5.15 INFO: rcu detected stall in mac80211_hwsim_beacon (3) 1 3 486d 493d 0/3 auto-obsoleted due to no activity on 2025/01/08 17:17
linux-6.1 INFO: rcu detected stall in mac80211_hwsim_beacon (2) 1 1 371d 371d 0/3 auto-obsoleted due to no activity on 2025/05/03 16:43
linux-6.1 INFO: rcu detected stall in mac80211_hwsim_beacon 1 3 485d 510d 0/3 auto-obsoleted due to no activity on 2025/01/08 20:04
upstream BUG: soft lockup in mac80211_hwsim_beacon (2) wireless 1 C error inconclusive 162 5d02h 689d 0/29 upstream: reported C repro on 2024/03/11 14:28
linux-5.15 INFO: rcu detected stall in mac80211_hwsim_beacon (2) 1 1 709d 709d 0/3 auto-obsoleted due to no activity on 2024/05/30 17:39
upstream BUG: soft lockup in mac80211_hwsim_beacon wireless 1 syz error unreliable 180 1374d 1947d 0/29 auto-obsoleted due to no activity on 2023/01/21 14:41

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (1 GPs behind) idle=7bd/1/0x4000000000000000 softirq=24349/24352 fqs=3870 
	(t=10500 jiffies g=34593 q=1352)
NMI backtrace for cpu 0
CPU: 0 PID: 10380 Comm: syz.1.1649 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <IRQ>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_dump_cpu_stacks+0x22f/0x380 kernel/rcu/tree_stall.h:349
 print_cpu_stall+0x31d/0x5f0 kernel/rcu/tree_stall.h:633
 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline]
 rcu_pending kernel/rcu/tree.c:3936 [inline]
 rcu_sched_clock_irq+0x6ea/0x1120 kernel/rcu/tree.c:2619
 update_process_times+0x193/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x4ad/0xb70 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x4d/0xc0 arch/x86/kernel/apic/apic.c:1108
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:seqcount_lockdep_reader_access+0x196/0x1d0 include/linux/seqlock.h:106
Code: 00 4d 85 e4 75 16 e8 b9 f7 0f 00 eb 15 e8 b2 f7 0f 00 e8 bd 10 51 08 4d 85 e4 74 ea e8 a3 f7 0f 00 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3e 00 00 00 00 43 c7 44 3e 08 00 00 00 00 65 48 8b 04 25
RSP: 0018:ffffc90000007b40 EFLAGS: 00000246
RAX: ffffffff816918ad RBX: 0000000000000000 RCX: ffff888022398000
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000007bf8 R08: ffff8880b903b30b R09: 1ffff11017207661
R10: dffffc0000000000 R11: ffffed1017207662 R12: 0000000000000200
R13: 0000000000019000 R14: 1ffff92000000f68 R15: dffffc0000000000
 ktime_get+0x31/0x270 kernel/time/timekeeping.c:829
 hrtimer_forward_now include/linux/hrtimer.h:508 [inline]
 mac80211_hwsim_beacon+0x13b/0x180 drivers/net/wireless/mac80211_hwsim.c:1874
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x4eb/0xb70 kernel/time/hrtimer.c:1749
 hrtimer_run_softirq+0x176/0x240 kernel/time/hrtimer.c:1766
 handle_softirqs+0x339/0x830 kernel/softirq.c:576
 __do_softirq kernel/softirq.c:610 [inline]
 invoke_softirq kernel/softirq.c:450 [inline]
 __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:preempt_schedule_irq+0xb6/0x160 kernel/sched/core.c:6799
Code: 00 00 43 c6 44 37 04 f8 74 0b 0f 0b 48 f7 03 08 00 00 00 74 7f bf 01 00 00 00 e8 15 e1 8f f7 e8 50 cb bc f7 fb bf 01 00 00 00 <e8> 65 b5 ff ff 43 c6 44 37 08 00 48 c7 44 24 40 00 00 00 00 9c 8f
RSP: 0018:ffffc90002e4f760 EFLAGS: 00000286
RAX: 6266ed3c61a68300 RBX: ffff888022398000 RCX: 6266ed3c61a68300
RDX: dffffc0000000000 RSI: ffffffff8a2b1c00 RDI: 0000000000000001
RBP: ffffc90002e4f800 R08: ffff8880b903b30b R09: 1ffff11017207661
R10: dffffc0000000000 R11: ffffed1017207662 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff920005c9eec
 irqentry_exit+0x63/0x70 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:free_unref_page+0x1ed/0x2a0 mm/page_alloc.c:3418
Code: 02 00 00 43 c6 44 3d 04 f8 0f 85 80 00 00 00 f7 c3 00 02 00 00 74 01 fb 48 c7 44 24 20 0e 36 e0 45 4b c7 44 3d 00 00 00 00 00 <43> c7 44 3d 08 00 00 00 00 65 48 8b 04 25 28 00 00 00 48 3b 84 24
RSP: 0018:ffffc90002e4f8c0 EFLAGS: 00000206
RAX: 6266ed3c61a68300 RBX: 0000000000000293 RCX: 6266ed3c61a68300
RDX: dffffc0000000000 RSI: ffffffff8a2b1c00 RDI: ffffffff8a79e740
RBP: ffffc90002e4f9a0 R08: ffff8880b903b30b R09: 1ffff11017207661
R10: dffffc0000000000 R11: ffffed1017207662 R12: ffffffff8be27820
R13: 1ffff920005c9f1c R14: ffffea00008f6a00 R15: dffffc0000000000
 qlist_free_all+0x35/0x90 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x150/0x160 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x2f/0xd0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3225 [inline]
 slab_alloc mm/slub.c:3233 [inline]
 __kmalloc+0x127/0x330 mm/slub.c:4408
 kmalloc include/linux/slab.h:612 [inline]
 sk_prot_alloc+0xe7/0x210 net/core/sock.c:1866
 sk_alloc+0x2f/0x310 net/core/sock.c:1922
 __netlink_create+0x6b/0x2d0 net/netlink/af_netlink.c:629
 netlink_create+0x3a7/0x510 net/netlink/af_netlink.c:692
 __sock_create+0x47b/0x900 net/socket.c:1496
 sock_create net/socket.c:1552 [inline]
 __sys_socket+0xe2/0x170 net/socket.c:1594
 __do_sys_socket net/socket.c:1603 [inline]
 __se_sys_socket net/socket.c:1601 [inline]
 __x64_sys_socket+0x76/0x80 net/socket.c:1601
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f83c9fe9cb9
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:00007f83c8224028 EFLAGS: 00000246 ORIG_RAX: 0000000000000029
RAX: ffffffffffffffda RBX: 00007f83ca265090 RCX: 00007f83c9fe9cb9
RDX: 0000000000000004 RSI: 0000000000000002 RDI: 0000000000000010
RBP: 00007f83ca057bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f83ca265128 R14: 00007f83ca265090 R15: 00007ffe1c6e37f8
 </TASK>

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/01/19 05:09 linux-5.15.y 68efe5a6c16a 20d37d28 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in mac80211_hwsim_beacon
2025/12/19 16:36 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in mac80211_hwsim_beacon
2025/11/18 00:10 linux-5.15.y cc5ec8769306 ef766cd7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in mac80211_hwsim_beacon
2025/09/09 14:57 linux-5.15.y 7a6c2d093c45 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in mac80211_hwsim_beacon
* Struck through repros no longer work on HEAD.