rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5874/1:b..l P1011/1:b..l P5959/1:b..l P6262/1:b..l P36/1:b..l P8941/1:b..l rcu: (detected by 0, t=10502 jiffies, g=46677, q=815 ncpus=2) task:syz-executor state:R running task stack:21592 pid:8941 tgid:8941 ppid:8932 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6863 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7047 preempt_schedule+0xae/0xc0 kernel/sched/core.c:7071 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] copy_pte_range mm/memory.c:1331 [inline] copy_pmd_range+0x74f2/0x7e00 mm/memory.c:1392 copy_pud_range mm/memory.c:1429 [inline] copy_p4d_range mm/memory.c:1453 [inline] copy_page_range+0xb88/0x11d0 mm/memory.c:1535 dup_mmap+0xf4a/0x1b80 mm/mmap.c:1827 dup_mm kernel/fork.c:1529 [inline] copy_mm+0x13c/0x4b0 kernel/fork.c:1581 copy_process+0x165d/0x3950 kernel/fork.c:2221 kernel_clone+0x21e/0x820 kernel/fork.c:2651 __do_sys_clone kernel/fork.c:2792 [inline] __se_sys_clone kernel/fork.c:2776 [inline] __x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2776 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc07ed85e93 RSP: 002b:00007fff65195f78 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fc07ed85e93 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 00005555940267d0 R11: 0000000000000246 R12: 0000000000000000 R13: 00000000000927c0 R14: 0000000000066ee2 R15: 00007fff65196110 task:kworker/u8:2 state:R running task stack:21672 pid:36 tgid:36 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events_unbound cfg80211_wiphy_work Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6863 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7190 irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:210 Code: 89 fb e8 23 00 00 00 48 8b 3d c4 8e d9 0b 48 89 de 5b e9 b3 32 5b 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 08 f0 7e 92 65 8b 15 c8 38 RSP: 0018:ffffc90000ac7650 EFLAGS: 00000293 RAX: 000000000000000c RBX: ffff88803437b140 RCX: 1ffff1100686f628 RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000040 RBP: ffff88803437b140 R08: 0000000000000000 R09: 000000000000000c R10: 000000000000000c R11: 0000000000000000 R12: 0000000000000004 R13: ffff88803437dcb0 R14: 0000000000000003 R15: ffff88803437dcb0 ieee80211_mandatory_rates+0x155/0x230 net/wireless/util.c:62 ieee80211_update_sta_info net/mac80211/ibss.c:990 [inline] ieee80211_rx_bss_info net/mac80211/ibss.c:1092 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1575 [inline] ieee80211_ibss_rx_queued_mgmt+0x136b/0x2af0 net/mac80211/ibss.c:1602 ieee80211_iface_process_skb net/mac80211/iface.c:1736 [inline] ieee80211_iface_work+0x85f/0x12d0 net/mac80211/iface.c:1790 cfg80211_wiphy_work+0x2ab/0x450 net/wireless/core.c:438 process_one_work+0x93a/0x15a0 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3443 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 task:kworker/u8:19 state:R running task stack:22168 pid:6262 tgid:6262 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events_unbound cfg80211_wiphy_work Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6863 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7190 irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_release+0x2a6/0x3b0 kernel/locking/lockdep.c:5893 Code: 4d 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 75 52 f7 c3 00 02 00 00 74 01 fb 65 48 8b 05 5a 3e e0 10 <48> 3b 44 24 28 75 75 48 83 c4 30 5b 41 5c 41 5d 41 5e 41 5f 5d e9 RSP: 0018:ffffc9000cfd7470 EFLAGS: 00000206 RAX: 478e5eaec7874700 RBX: 0000000000000202 RCX: 478e5eaec7874700 RDX: 0000000000000003 RSI: ffffffff8d97a720 RDI: ffffffff8bc08360 RBP: ffff88802fad6728 R08: ffffc9000cfd7607 R09: 0000000000000000 R10: ffffc9000cfd75f8 R11: fffff520019faec1 R12: 0000000000000003 R13: 0000000000000003 R14: ffffffff8df41a60 R15: ffff88802fad5b80 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:897 [inline] class_rcu_destructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0x1ab1/0x23d0 arch/x86/kernel/unwind_orc.c:695 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6670 [inline] kmem_cache_free+0x197/0x620 mm/slub.c:6781 kfree_skb_reason include/linux/skbuff.h:1322 [inline] kfree_skb include/linux/skbuff.h:1331 [inline] ieee80211_iface_work+0xb2a/0x12d0 net/mac80211/iface.c:1792 cfg80211_wiphy_work+0x2ab/0x450 net/wireless/core.c:438 process_one_work+0x93a/0x15a0 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3443 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 task:kworker/u8:12 state:R running task stack:21512 pid:5959 tgid:5959 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events_unbound cfg80211_wiphy_work Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6863 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7190 irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_release+0x2a6/0x3b0 kernel/locking/lockdep.c:5893 Code: 4d 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 75 52 f7 c3 00 02 00 00 74 01 fb 65 48 8b 05 5a 3e e0 10 <48> 3b 44 24 28 75 75 48 83 c4 30 5b 41 5c 41 5d 41 5e 41 5f 5d e9 RSP: 0018:ffffc90004bf73b0 EFLAGS: 00000206 RAX: 5219018c1d455200 RBX: 0000000000000202 RCX: 5219018c1d455200 RDX: 0000000000000003 RSI: ffffffff8d97a720 RDI: ffffffff8bc08360 RBP: ffff88802ca9aa28 R08: ffffc90004bf7a20 R09: 0000000000000000 R10: ffffc90004bf7538 R11: fffff5200097eea9 R12: 0000000000000003 R13: 0000000000000003 R14: ffffffff8df41a60 R15: ffff88802ca99e80 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:897 [inline] class_rcu_destructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0x1ab1/0x23d0 arch/x86/kernel/unwind_orc.c:695 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6670 [inline] kmem_cache_free+0x197/0x620 mm/slub.c:6781 skb_release_data+0x62d/0x7c0 net/core/skbuff.c:1107 skb_release_all net/core/skbuff.c:1182 [inline] __kfree_skb net/core/skbuff.c:1196 [inline] sk_skb_reason_drop+0x127/0x170 net/core/skbuff.c:1234 kfree_skb_reason include/linux/skbuff.h:1322 [inline] kfree_skb include/linux/skbuff.h:1331 [inline] ieee80211_iface_work+0xb2a/0x12d0 net/mac80211/iface.c:1792 cfg80211_wiphy_work+0x2ab/0x450 net/wireless/core.c:438 process_one_work+0x93a/0x15a0 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3443 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 task:kworker/u8:6 state:R running task stack:23320 pid:1011 tgid:1011 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events_unbound cfg80211_wiphy_work Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6863 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7190 irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:210 Code: 89 fb e8 23 00 00 00 48 8b 3d c4 8e d9 0b 48 89 de 5b e9 b3 32 5b 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 08 f0 7e 92 65 8b 15 c8 38 RSP: 0018:ffffc90003d3f600 EFLAGS: 00000206 RAX: ffffffff8add4dc8 RBX: 00000000000000f0 RCX: ffff888026998000 RDX: 0000000000000000 RSI: 00000000000000f0 RDI: 000000000000003c RBP: 000000000000003c R08: 0000000000000000 R09: 000000000000000c R10: 000000000000000c R11: 0000000000000000 R12: 1ffff11006506626 R13: ffff888063ffd001 R14: 0000000000000008 R15: ffff888032833130 ieee80211_sta_get_rates+0x3a9/0x5d0 net/mac80211/util.c:1547 ieee80211_update_sta_info net/mac80211/ibss.c:982 [inline] ieee80211_rx_bss_info net/mac80211/ibss.c:1092 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1575 [inline] ieee80211_ibss_rx_queued_mgmt+0x131a/0x2af0 net/mac80211/ibss.c:1602 ieee80211_iface_process_skb net/mac80211/iface.c:1736 [inline] ieee80211_iface_work+0x85f/0x12d0 net/mac80211/iface.c:1790 cfg80211_wiphy_work+0x2ab/0x450 net/wireless/core.c:438 process_one_work+0x93a/0x15a0 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3443 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 task:udevd state:R running task stack:22712 pid:5874 tgid:5874 ppid:5197 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6863 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7190 irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_acquire+0x16c/0x340 kernel/locking/lockdep.c:5872 Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 74 70 e0 10 <48> 3b 44 24 58 0f 85 e5 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc9000441f278 EFLAGS: 00000206 RAX: d895bae11250c400 RBX: 0000000000000000 RCX: d895bae11250c400 RDX: 000000006f1c9d3a RSI: ffffffff8d97a720 RDI: ffffffff8bc08360 RBP: ffffffff81743f85 R08: ffffffff81743f85 R09: ffffffff8df41a60 R10: ffffc9000441f438 R11: ffffffff81ada980 R12: 0000000000000002 R13: ffffffff8df41a60 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:867 [inline] class_rcu_constructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0xc2/0x23d0 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4953 [inline] slab_alloc_node mm/slub.c:5263 [inline] kmem_cache_alloc_lru_noprof+0x36c/0x6e0 mm/slub.c:5282 shmem_alloc_inode+0x28/0x40 mm/shmem.c:5156 alloc_inode+0x6a/0x1b0 fs/inode.c:346 new_inode+0x22/0x170 fs/inode.c:1175 __shmem_get_inode mm/shmem.c:3068 [inline] shmem_get_inode+0x347/0xe60 mm/shmem.c:3142 shmem_mknod+0x191/0x360 mm/shmem.c:3872 lookup_open fs/namei.c:4440 [inline] open_last_lookups fs/namei.c:4540 [inline] path_openat+0x18bb/0x3dd0 fs/namei.c:4784 do_filp_open+0x1fa/0x410 fs/namei.c:4814 do_sys_openat2+0x121/0x200 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1447 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4677aa7407 RSP: 002b:00007ffde2a4b840 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f46781a2880 RCX: 00007f4677aa7407 RDX: 00000000000a0241 RSI: 00007ffde2a4c500 RDI: ffffffffffffff9c RBP: 000055a5a598c370 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000124 R11: 0000000000000202 R12: 000055a5a5949650 R13: 00007ffde2a4c500 R14: 00007ffde2a4c100 R15: 00007ffde2a4bd00 rcu: rcu_preempt kthread starved for 10707 jiffies! g46677 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:27136 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82 Code: cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 13 50 0c 00 f3 0f 1e fa fb f4 c8 ed 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90000197de0 EFLAGS: 000002c6 RAX: a416a61f450fa600 RBX: ffffffff8197983a RCX: a416a61f450fa600 RDX: 0000000000000001 RSI: ffffffff8d7939c1 RDI: ffffffff8bc08360 RBP: ffffc90000197f10 R08: ffff8880b87336db R09: 1ffff110170e66db R10: dffffc0000000000 R11: ffffed10170e66dc R12: ffffffff8f822a70 R13: 1ffff110039dcb70 R14: 0000000000000001 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff888125f31000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdef6be58a0 CR3: 000000007918e000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x73/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1ea/0x520 kernel/sched/idle.c:332 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312 common_startup_64+0x13e/0x147