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INFO: rcu detected stall in cfg80211_wiphy_work

Status: upstream: reported on 2026/03/26 20:13
Reported-by: syzbot+5c07d86ad5d5e3beb656@syzkaller.appspotmail.com
First crash: 3d08h, last: 3d08h
▶ ▼ Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in cfg80211_wiphy_work wireless 1 C done done 4 808d 959d 0/29 auto-obsoleted due to no activity on 2024/04/20 07:53
linux-5.15 INFO: rcu detected stall in cfg80211_wiphy_work 1 1 45d 45d 0/3 upstream: reported on 2026/02/12 07:13
upstream INFO: rcu detected stall in cfg80211_wiphy_work (2) wireless 1 C done error 90 64d 496d 0/29 upstream: reported C repro on 2024/11/18 08:54

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P20191/1:b..l P4326/1:b..l
	(detected by 0, t=10502 jiffies, g=205521, q=58 ncpus=2)
task:kworker/u4:6    state:R  running task     stack:23152 pid:4326  ppid:2      flags:0x00004000
Workqueue: events_unbound cfg80211_wiphy_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:212
Code: 2e 0f 1f 84 00 00 00 00 00 90 53 48 89 fb e8 17 00 00 00 48 8b 3d 90 6c 9d 0c 48 89 de 5b e9 97 41 50 00 00 00 cc cc 00 00 cc <48> 8b 04 24 65 48 8b 0d a4 fa 7f 7e 65 8b 15 a5 fa 7f 7e 81 e2 00
RSP: 0018:ffffc900040c77f0 EFLAGS: 00000216
RAX: ffffffff89b38f2a RBX: 0000000000000008 RCX: 0000000000000000
RDX: ffff88802486d940 RSI: 000000000000006e RDI: 00000000000000f0
RBP: 00000000000000f0 R08: ffffffff8e1fdeef R09: 1ffffffff1c3fbdd
R10: dffffc0000000000 R11: fffffbfff1c3fbde R12: 000000000000000b
R13: 000000000000006e R14: dffffc0000000000 R15: ffff88807b703350
 ieee80211_sta_get_rates+0x422/0x6b0 net/mac80211/util.c:2198
 ieee80211_update_sta_info net/mac80211/ibss.c:1003 [inline]
 ieee80211_rx_bss_info net/mac80211/ibss.c:1118 [inline]
 ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1609 [inline]
 ieee80211_ibss_rx_queued_mgmt+0x10ad/0x2cd0 net/mac80211/ibss.c:1638
 ieee80211_iface_process_skb net/mac80211/iface.c:1679 [inline]
 ieee80211_iface_work+0x726/0xc80 net/mac80211/iface.c:1733
 cfg80211_wiphy_work+0x221/0x260 net/wireless/core.c:433
 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
task:kworker/u4:26   state:R  running task     stack:23952 pid:20191 ppid:2      flags:0x00004000
Workqueue: events_unbound cfg80211_wiphy_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_common_interrupt+0x22/0x40 arch/x86/include/asm/idtentry.h:682
RIP: 0010:ieee80211_sta_get_rates+0x362/0x6b0 net/mac80211/util.c:-1
Code: 4c 89 ff e8 20 f1 1f f8 48 63 c3 48 8d 2c 40 48 c1 e5 02 49 03 2f 48 89 e8 48 c1 e8 03 42 0f b6 04 30 84 c0 0f 85 f9 00 00 00 <44> 8b 75 00 44 0b 74 24 3c bf ff ff ff ff 44 89 f6 e8 28 e9 ce f7
RSP: 0018:ffffc9000400f7f8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000008 RCX: ffff88802b660000
RDX: 0000000000000000 RSI: 0000000000000168 RDI: 00000000000000b4
RBP: ffff888067555f18 R08: ffffffff8e1fdeef R09: 1ffffffff1c3fbdd
R10: dffffc0000000000 R11: fffffbfff1c3fbde R12: 000000000000000b
R13: 0000000000000168 R14: dffffc0000000000 R15: ffff888067553350
 ieee80211_update_sta_info net/mac80211/ibss.c:1003 [inline]
 ieee80211_rx_bss_info net/mac80211/ibss.c:1118 [inline]
 ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1609 [inline]
 ieee80211_ibss_rx_queued_mgmt+0x10ad/0x2cd0 net/mac80211/ibss.c:1638
 ieee80211_iface_process_skb net/mac80211/iface.c:1679 [inline]
 ieee80211_iface_work+0x726/0xc80 net/mac80211/iface.c:1733
 cfg80211_wiphy_work+0x221/0x260 net/wireless/core.c:433
 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: rcu_preempt kthread starved for 9886 jiffies! g205521 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:27728 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 schedule+0xb9/0x180 kernel/sched/core.c:6638
 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168
 rcu_gp_fqs_loop+0x303/0x1340 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x99/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 1 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:741

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/26 20:12 linux-6.1.y 1989cd3d56e2 766b6434 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in cfg80211_wiphy_work
* Struck through repros no longer work on HEAD.