INFO: rcu detected stall in mac80211_hwsim_beacon (2)

Status: auto-obsoleted due to no activity on 2025/05/03 16:43
Reported-by: syzbot+0f64c5b529d88e65665a@syzkaller.appspotmail.com
First crash: 557d, last: 557d
▶ ▼ Similar bugs (12)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in mac80211_hwsim_beacon (4) origin:lts-only 1 syz, C error 13 11d 110d 0/3 upstream: reported C repro on 2026/04/15 21:01
upstream INFO: rcu detected stall in mac80211_hwsim_beacon kernel 1 syz, C error inconclusive 1904 1561d 2140d 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 349d 349d 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 1019d 1019d 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 672d 680d 0/3 auto-obsoleted due to no activity on 2025/01/08 17:17
linux-5.15 INFO: rcu detected stall in mac80211_hwsim_beacon (4) 1 8 89d 328d 0/3 upstream: reported on 2025/09/09 14:58
linux-6.1 INFO: rcu detected stall in mac80211_hwsim_beacon 1 3 672d 697d 0/3 auto-obsoleted due to no activity on 2025/01/08 20:04
linux-6.6 INFO: rcu detected stall in mac80211_hwsim_beacon origin:lts-only 1 syz, C 2 18d 55d 0/2 upstream: reported C repro on 2026/06/10 10:49
upstream BUG: soft lockup in mac80211_hwsim_beacon (2) wireless prio:high 1 syz, C error inconclusive 171 114d 875d 0/29 auto-obsoleted due to no activity on 2026/06/21 00:56
linux-5.15 INFO: rcu detected stall in mac80211_hwsim_beacon (2) 1 1 895d 895d 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 1561d 2133d 0/29 auto-obsoleted due to no activity on 2023/01/21 14:41
upstream BUG: soft lockup in mac80211_hwsim_beacon (3) virt prio:normal 1 2 8d06h 5d07h 0/29 moderation: reported on 2026/07/30 07:17

Sample crash report:
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-.... } 2719 jiffies s: 57825 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: 9225 Comm: syz.9.1357 Not tainted 6.1.126-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:check_preemption_disabled+0x4b/0x110 lib/smp_processor_id.c:55
Code: 8b 05 21 91 4f 75 a9 ff ff ff 7f 74 22 65 48 8b 04 25 28 00 00 00 48 3b 44 24 08 0f 85 c7 00 00 00 89 d8 48 83 c4 10 5b 41 5c <41> 5e 41 5f c3 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02
RSP: 0018:ffffc900001dffc8 EFLAGS: 00000086
RAX: 0000000000000001 RBX: ffffc900001e0040 RCX: ffffffff816b5ea2
RDX: dffffc0000000000 RSI: ffffffff8b0c14c0 RDI: ffffffff8b5e67c0
RBP: ffffc900001e0128 R08: dffffc0000000000 R09: fffffbfff2249c4e
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200003c004
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000046
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555908b65c8 CR3: 00000000250b6000 CR4: 00000000003506e0
DR0: 0000000020000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 lockdep_recursion_finish kernel/locking/lockdep.c:467 [inline]
 lock_acquire+0x208/0x5a0 kernel/locking/lockdep.c:5664
 seqcount_lockdep_reader_access+0xf8/0x220 include/linux/seqlock.h:102
 timekeeping_get_delta kernel/time/timekeeping.c:254 [inline]
 timekeeping_get_ns kernel/time/timekeeping.c:388 [inline]
 ktime_get+0x7f/0x270 kernel/time/timekeeping.c:848
 hrtimer_forward_now include/linux/hrtimer.h:508 [inline]
 perf_swevent_hrtimer+0x43b/0x4f0 kernel/events/core.c:10885
 __run_hrtimer kernel/time/hrtimer.c:1689 [inline]
 __hrtimer_run_queues+0x5a7/0xe50 kernel/time/hrtimer.c:1753
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1815
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x158/0x5b0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x4d/0xc0 arch/x86/kernel/apic/apic.c:1118
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:memset+0x1/0x40 mm/kasan/shadow.c:43
Code: 8c ce 08 31 db eb d7 cc cc 89 f6 48 8b 0c 24 31 d2 e9 d3 ec ff ff 0f 1f 00 89 f6 48 8b 0c 24 ba 01 00 00 00 e9 c0 ec ff ff 55 <41> 56 53 48 89 d3 41 89 f6 48 89 fd 48 8b 4c 24 18 48 89 d6 ba 01
RSP: 0018:ffffc900001e0808 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff8880242a6c00 RCX: ffffffff88a00b2b
RDX: 0000000000000020 RSI: 0000000000000000 RDI: ffff8880242a6cc0
RBP: 00000000000000c0 R08: dffffc0000000000 R09: ffffed100fe881d5
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff1100fe881d1
R13: ffff88807f440dc0 R14: dffffc0000000000 R15: 1ffff1100fe881d2
 __build_skb_around net/core/skbuff.c:293 [inline]
 __alloc_skb+0x383/0x670 net/core/skbuff.c:530
 skb_copy+0x127/0x820 net/core/skbuff.c:1732
 mac80211_hwsim_tx_frame_no_nl+0x10f4/0x1a70 drivers/net/wireless/mac80211_hwsim.c:1724
 mac80211_hwsim_tx_frame+0x1cc/0x220 drivers/net/wireless/mac80211_hwsim.c:2053
 mac80211_hwsim_beacon_tx+0x5f8/0xaa0 drivers/net/wireless/mac80211_hwsim.c:2116
 __iterate_interfaces+0x21e/0x4b0 net/mac80211/util.c:788
 ieee80211_iterate_active_interfaces_atomic+0xd4/0x170 net/mac80211/util.c:824
 mac80211_hwsim_beacon+0xd0/0x1e0 drivers/net/wireless/mac80211_hwsim.c:2142
 __run_hrtimer kernel/time/hrtimer.c:1689 [inline]
 __hrtimer_run_queues+0x5e5/0xe50 kernel/time/hrtimer.c:1753
 hrtimer_run_softirq+0x196/0x2c0 kernel/time/hrtimer.c:1770
 handle_softirqs+0x2ee/0xa40 kernel/softirq.c:571
 __do_softirq kernel/softirq.c:605 [inline]
 invoke_softirq kernel/softirq.c:445 [inline]
 __irq_exit_rcu+0x157/0x240 kernel/softirq.c:654
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:666
 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:preempt_schedule_irq+0xf2/0x1c0 kernel/sched/core.c:6870
Code: 89 f5 49 c1 ed 03 eb 0d 48 f7 03 08 00 00 00 0f 84 97 00 00 00 bf 01 00 00 00 e8 19 1b a3 f6 e8 84 e9 d5 f6 fb bf 01 00 00 00 <e8> 79 b4 ff ff 43 80 7c 3d 00 00 74 08 4c 89 f7 e8 29 bc 26 f7 48
RSP: 0018:ffffc900050c70c0 EFLAGS: 00000282
RAX: 2fc84f4049fe7800 RBX: 1ffff92000a18e20 RCX: ffffffff816b126a
RDX: dffffc0000000000 RSI: ffffffff8b0c0340 RDI: 0000000000000001
RBP: ffffc900050c7170 R08: dffffc0000000000 R09: fffffbfff2249c53
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000a18e18
R13: 1ffff92000a18e1c R14: ffffc900050c70e0 R15: dffffc0000000000
 irqentry_exit+0x53/0x80 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:kasan_check_range+0x6/0x290 mm/kasan/generic.c:188
Code: e8 2f 55 d1 08 31 c0 c3 0f 0b b8 ea ff ff ff c3 0f 0b b8 ea ff ff ff c3 cc cc cc cc cc cc cc cc cc cc cc cc 55 41 57 41 56 53 <b0> 01 48 85 f6 0f 84 9a 01 00 00 48 89 fd 48 01 f5 0f 82 5a 02 00
RSP: 0018:ffffc900050c7238 EFLAGS: 00000246
RAX: ffffffff81d91ec1 RBX: ffffea0001926500 RCX: ffffffff81d91ed2
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffea0001926500
RBP: dffffc0000000000 R08: ffffffff81d91ead R09: fffff94000324ca9
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffea0001926508
R13: 1ffffd4000324ca1 R14: 00000000000001fe R15: 0000000000000fe8
 instrument_atomic_read include/linux/instrumented.h:72 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 folio_test_swapbacked include/linux/page-flags.h:502 [inline]
 folio_test_swapcache include/linux/page-flags.h:543 [inline]
 free_swap_cache+0xc2/0x650 mm/swap_state.c:284
 free_pages_and_swap_cache+0x5e/0x90 mm/swap_state.c:313
 tlb_batch_pages_flush mm/mmu_gather.c:59 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:254 [inline]
 tlb_flush_mmu+0xfc/0x210 mm/mmu_gather.c:261
 zap_pte_range mm/memory.c:1525 [inline]
 zap_pmd_range mm/memory.c:1574 [inline]
 zap_pud_range mm/memory.c:1603 [inline]
 zap_p4d_range mm/memory.c:1624 [inline]
 unmap_page_range+0x217c/0x2740 mm/memory.c:1645
 unmap_vmas+0x48b/0x640 mm/memory.c:1730
 exit_mmap+0x249/0x980 mm/mmap.c:3238
 __mmput+0x115/0x3c0 kernel/fork.c:1200
 exit_mm+0x226/0x300 kernel/exit.c:565
 do_exit+0x9f1/0x26a0 kernel/exit.c:858
 do_group_exit+0x202/0x2b0 kernel/exit.c:1021
 get_signal+0x16f7/0x17d0 kernel/signal.c:2871
 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x6a/0x100 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+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fa9cbb85d29
Code: Unable to access opcode bytes at 0x7fa9cbb85cff.
RSP: 002b:00007fa9cc9e10e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007fa9cbd75fa8 RCX: 00007fa9cbb85d29
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fa9cbd75fac
RBP: 00007fa9cbd75fa0 R08: 0000000000000010 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 00007fa9cbd75fac
R13: 0000000000000000 R14: 00007ffda59aa9c0 R15: 00007ffda59aaaa8
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/01/23 16:42 linux-6.1.y f4f677285b38 a44b0418 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in mac80211_hwsim_beacon
* Struck through repros no longer work on HEAD.