rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5248/2:b..l rcu: (detected by 0, t=10502 jiffies, g=7873, q=44 ncpus=2) task:udevd state:R running task stack:23440 pid:5248 tgid:5248 ppid:4681 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6851 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:seqcount_lockdep_reader_access+0x1d6/0x220 include/linux/seqlock.h:75 Code: 62 e8 ae af 76 ff 4d 85 f6 48 bb 00 00 00 00 00 fc ff df 75 07 e8 9a af 76 ff eb 06 e8 93 af 76 ff fb 48 c7 04 24 0e 36 e0 45 <4a> c7 04 23 00 00 00 00 66 42 c7 44 23 09 00 00 42 c6 44 23 0b 00 RSP: 0018:ffffc90009c472a0 EFLAGS: 00000293 RAX: ffffffff821cdd1d RBX: dffffc0000000000 RCX: ffff8880728e1e00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90009c47350 R08: ffffffff821cdcf8 R09: 1ffffffff283c90f R10: dffffc0000000000 R11: fffffbfff283c910 R12: 1ffff92001388e54 R13: ffffc90009c472c0 R14: 0000000000000200 R15: 0000000000000046 read_seqbegin include/linux/seqlock.h:772 [inline] read_seqbegin_or_lock include/linux/seqlock.h:1076 [inline] prepend_path+0x2d6/0xbe0 fs/d_path.c:171 d_absolute_path+0x179/0x310 fs/d_path.c:234 tomoyo_get_absolute_path security/tomoyo/realpath.c:101 [inline] tomoyo_realpath_from_path+0x2b4/0x5e0 security/tomoyo/realpath.c:271 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x255/0x500 security/tomoyo/file.c:771 security_file_open+0x6c/0x750 security/security.c:2988 do_dentry_open+0x38e/0x1440 fs/open.c:946 vfs_open+0x3e/0x330 fs/open.c:1089 do_open fs/namei.c:3727 [inline] path_openat+0x2b3e/0x3470 fs/namei.c:3886 do_filp_open+0x235/0x490 fs/namei.c:3913 do_sys_openat2+0x13e/0x1d0 fs/open.c:1416 do_sys_open fs/open.c:1431 [inline] __do_sys_openat fs/open.c:1447 [inline] __se_sys_openat fs/open.c:1442 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1442 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0f3d5169a4 RSP: 002b:00007ffe4ac26870 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00005607882cee10 RCX: 00007f0f3d5169a4 RDX: 0000000000080000 RSI: 00007ffe4ac26988 RDI: 00000000ffffff9c RBP: 00007ffe4ac26988 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000080000 R13: 00005607882cef00 R14: 00007ffe4ac26988 R15: 00005607882b8f00 rcu: rcu_preempt kthread starved for 431 jiffies! g7873 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:23544 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2034 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2236 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 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: 101 PID: 4894 Comm: dhcpcd Not tainted 6.11.0-rc6-syzkaller-00326-gd1f2d51b711a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:__usb_hcd_giveback_urb+0x3d3/0x6e0 drivers/usb/core/hcd.c:1649 Code: bf 00 02 00 00 be 00 02 00 00 48 21 de 31 ff e8 33 0a 68 fa 49 21 df 75 07 e8 49 05 68 fa eb 0a e8 42 05 68 fa e8 7d 6b 6f fa <49> be 00 00 00 00 00 fc ff df bf ff ff ff ff 44 89 e6 e8 66 09 68 RSP: 0018:ffffc90000a17fc0 EFLAGS: 00000006 RAX: ffffffff872b8767 RBX: 0000000000000046 RCX: ffff88802f1b8000 RDX: 0000000000010100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000a18090 R08: ffffffff872b875d R09: 1ffff1100636765f R10: dffffc0000000000 R11: ffffed1006367660 R12: 0000000000000003 R13: ffff88802eaf2d00 R14: ffffc90000a18020 R15: 0000000000000000 FS: 00007f085921e740(0000) GS:ffff8880b8900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffcc9fff7a8 CR3: 0000000028bae000 CR4: 0000000000350ef0 Call Trace: dummy_timer+0x830/0x45a0 drivers/usb/gadget/udc/dummy_hcd.c:1987 __run_hrtimer kernel/time/hrtimer.c:1689 [inline] __hrtimer_run_queues+0x59d/0xd50 kernel/time/hrtimer.c:1753 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1815 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x112/0x3f0 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:430 [inline] RIP: 0010:__pv_queued_spin_lock_slowpath+0x784/0xdb0 kernel/locking/qspinlock.c:508 Code: b6 04 2b 84 c0 75 6c 66 c7 84 24 b0 00 00 00 00 01 48 8b 44 24 40 42 0f b6 04 28 84 c0 75 77 41 80 3e 00 74 0c f3 90 41 ff c4 <75> d2 e9 a0 00 00 00 4c 89 f7 be 02 00 00 00 e8 f8 e5 36 f6 48 8d RSP: 0018:ffffc90000a18700 EFLAGS: 00000286 RAX: 0000000000000000 RBX: 1ffff920001430f6 RCX: ffffc90000a18701 RDX: 0000000000000100 RSI: ffffffff8c0ad560 RDI: ffffffff8c608e80 RBP: ffffc90000a18838 R08: ffffffff941e48af R09: 1ffffffff283c915 R10: dffffc0000000000 R11: fffffbfff283c916 R12: 00000000ffff9f33 R13: dffffc0000000000 R14: ffffffff8f4eb000 R15: ffffc90000a187c0 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:584 [inline] queued_spin_lock_slowpath+0x42/0x50 arch/x86/include/asm/qspinlock.h:51 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline] do_raw_spin_lock+0x272/0x370 kernel/locking/spinlock_debug.c:116 spin_lock include/linux/spinlock.h:351 [inline] mac80211_hwsim_tx_frame_no_nl+0x982/0x18d0 drivers/net/wireless/virtual/mac80211_hwsim.c:1817 mac80211_hwsim_tx_frame+0x1cc/0x220 drivers/net/wireless/virtual/mac80211_hwsim.c:2215 mac80211_hwsim_beacon_tx+0x3bf/0x850 drivers/net/wireless/virtual/mac80211_hwsim.c:2315 __iterate_interfaces+0x224/0x510 net/mac80211/util.c:772 ieee80211_iterate_active_interfaces_atomic+0xd8/0x170 net/mac80211/util.c:808 mac80211_hwsim_beacon+0xd4/0x1f0 drivers/net/wireless/virtual/mac80211_hwsim.c:2345 __run_hrtimer kernel/time/hrtimer.c:1689 [inline] __hrtimer_run_queues+0x59d/0xd50 kernel/time/hrtimer.c:1753 hrtimer_run_softirq+0x19a/0x2c0 kernel/time/hrtimer.c:1770 handle_softirqs+0x2c6/0x970 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xd8/0x140 kernel/locking/spinlock.c:194 Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 ae 0a 37 f6 f6 44 24 21 02 75 52 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 f3 37 9f f5 65 8b 05 c4 0d 40 74 85 c0 74 43 48 c7 04 24 0e 36 RSP: 0018:ffffc9000a0e7400 EFLAGS: 00000206 RAX: 7518073d50f92f00 RBX: 1ffff9200141ce84 RCX: ffffffff81703fea RDX: dffffc0000000000 RSI: ffffffff8c0ad560 RDI: 0000000000000001 RBP: ffffc9000a0e7498 R08: ffffffff941e4877 R09: 1ffffffff283c90e R10: dffffc0000000000 R11: fffffbfff283c90f R12: dffffc0000000000 R13: 1ffff9200141ce80 R14: ffffc9000a0e7420 R15: 0000000000000246 __slab_free+0x2c5/0x3d0 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9e/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:322 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3992 [inline] slab_alloc_node mm/slub.c:4041 [inline] kmem_cache_alloc_node_noprof+0x16b/0x320 mm/slub.c:4084 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:664 alloc_skb include/linux/skbuff.h:1320 [inline] alloc_skb_with_frags+0xc3/0x770 net/core/skbuff.c:6526 sock_alloc_send_pskb+0x91a/0xa60 net/core/sock.c:2815 unix_dgram_sendmsg+0x6d3/0x1f80 net/unix/af_unix.c:2030 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x223/0x270 net/socket.c:745 sock_write_iter+0x2dd/0x400 net/socket.c:1160 new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa74/0xc90 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f08592e8bf2 Code: 89 c7 48 89 44 24 08 e8 7b 34 fa ff 48 8b 44 24 08 48 83 c4 28 c3 c3 64 8b 04 25 18 00 00 00 85 c0 75 20 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 6f 48 8b 15 07 a2 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007fffdeaa2f28 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000564ce3703770 RCX: 00007f08592e8bf2 RDX: 0000000000000048 RSI: 00007fffdeaa2f40 RDI: 0000000000000005 RBP: 00007fffdeaa2f40 R08: 0000000000000008 R09: 0000000000000037 R10: 0000000000000000 R11: 0000000000000246 R12: 0000564cc5efeefc R13: 00007fffdeaa3370 R14: 0000564ce37d12e0 R15: 0000000000000001