rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 0, t=10502 jiffies, g=127953, q=111 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10492 (4295135461-4295124969), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10492 jiffies! g127953 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 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:25816 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0x18bc/0x4c40 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6856 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2024 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2226 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 UID: 0 PID: 23910 Comm: syz.7.5064 Not tainted 6.14.0-rc1-syzkaller-00020-g0de63bb7d919 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x1ba4/0x2d30 kernel/smp.c:885 Code: 03 84 c0 75 7e 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 b0 e8 0b 00 41 83 e4 01 4c 8b 64 24 68 75 07 e8 60 e4 0b 00 eb 41 f3 90 <48> b8 00 00 00 00 00 fc ff df 0f b6 04 03 84 c0 75 11 41 f7 45 00 RSP: 0018:ffffc9000d667680 EFLAGS: 00000293 RAX: ffffffff81b37985 RBX: 1ffff110170e88c9 RCX: ffff888026eb0000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000d667880 R08: ffffffff81b37950 R09: 1ffffffff285870e R10: dffffc0000000000 R11: fffffbfff285870f R12: ffff8880b863f9c8 R13: ffff8880b8744648 R14: ffff8880b863f9c0 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2d11fffc CR3: 00000000629d2000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000001000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline] flush_tlb_multi arch/x86/mm/tlb.c:966 [inline] flush_tlb_mm_range+0x42d/0x710 arch/x86/mm/tlb.c:1054 tlb_flush arch/x86/include/asm/tlb.h:20 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:481 [inline] tlb_flush_mmu+0x1aa/0x680 mm/mmu_gather.c:395 tlb_finish_mmu+0xd4/0x200 mm/mmu_gather.c:488 exit_mmap+0x52a/0xd40 mm/mmap.c:1297 __mmput+0x115/0x410 kernel/fork.c:1356 exit_mm+0x220/0x310 kernel/exit.c:570 do_exit+0x9ad/0x28e0 kernel/exit.c:925 do_group_exit+0x207/0x2c0 kernel/exit.c:1087 __do_sys_exit_group kernel/exit.c:1098 [inline] __se_sys_exit_group kernel/exit.c:1096 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1096 x64_sys_call+0x26a8/0x26b0 arch/x86/include/generated/asm/syscalls_64.h:232 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: 0033:0x7fe75e78cda9 Code: Unable to access opcode bytes at 0x7fe75e78cd7f. RSP: 002b:00007ffdd786b998 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fe75e78cda9 RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffdd786b9fc R08: 00007ffdd786ba8f R09: 00000000000927c0 R10: 0000000000000001 R11: 0000000000000246 R12: 000000000000025c R13: 00000000000927c0 R14: 00000000001ca8a8 R15: 00007ffdd786ba50 watchdog: BUG: soft lockup - CPU#0 stuck for 263s! [syz.7.5064:23910] Modules linked in: irq event stamp: 750106 hardirqs last enabled at (750105): [] irqentry_exit+0x63/0x90 kernel/entry/common.c:357 hardirqs last disabled at (750106): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1049 softirqs last enabled at (750076): [] __do_softirq kernel/softirq.c:595 [inline] softirqs last enabled at (750076): [] invoke_softirq kernel/softirq.c:435 [inline] softirqs last enabled at (750076): [] __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662 softirqs last disabled at (749991): [] __do_softirq kernel/softirq.c:595 [inline] softirqs last disabled at (749991): [] invoke_softirq kernel/softirq.c:435 [inline] softirqs last disabled at (749991): [] __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662 CPU: 0 UID: 0 PID: 23910 Comm: syz.7.5064 Not tainted 6.14.0-rc1-syzkaller-00020-g0de63bb7d919 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x1ba4/0x2d30 kernel/smp.c:885 Code: 03 84 c0 75 7e 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 b0 e8 0b 00 41 83 e4 01 4c 8b 64 24 68 75 07 e8 60 e4 0b 00 eb 41 f3 90 <48> b8 00 00 00 00 00 fc ff df 0f b6 04 03 84 c0 75 11 41 f7 45 00 RSP: 0018:ffffc9000d667680 EFLAGS: 00000293 RAX: ffffffff81b37985 RBX: 1ffff110170e88c9 RCX: ffff888026eb0000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000d667880 R08: ffffffff81b37950 R09: 1ffffffff285870e R10: dffffc0000000000 R11: fffffbfff285870f R12: ffff8880b863f9c8 R13: ffff8880b8744648 R14: ffff8880b863f9c0 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2d11fffc CR3: 00000000629d2000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000001000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline] flush_tlb_multi arch/x86/mm/tlb.c:966 [inline] flush_tlb_mm_range+0x42d/0x710 arch/x86/mm/tlb.c:1054 tlb_flush arch/x86/include/asm/tlb.h:20 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:481 [inline] tlb_flush_mmu+0x1aa/0x680 mm/mmu_gather.c:395 tlb_finish_mmu+0xd4/0x200 mm/mmu_gather.c:488 exit_mmap+0x52a/0xd40 mm/mmap.c:1297 __mmput+0x115/0x410 kernel/fork.c:1356 exit_mm+0x220/0x310 kernel/exit.c:570 do_exit+0x9ad/0x28e0 kernel/exit.c:925 do_group_exit+0x207/0x2c0 kernel/exit.c:1087 __do_sys_exit_group kernel/exit.c:1098 [inline] __se_sys_exit_group kernel/exit.c:1096 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1096 x64_sys_call+0x26a8/0x26b0 arch/x86/include/generated/asm/syscalls_64.h:232 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: 0033:0x7fe75e78cda9 Code: Unable to access opcode bytes at 0x7fe75e78cd7f. RSP: 002b:00007ffdd786b998 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fe75e78cda9 RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffdd786b9fc R08: 00007ffdd786ba8f R09: 00000000000927c0 R10: 0000000000000001 R11: 0000000000000246 R12: 000000000000025c R13: 00000000000927c0 R14: 00000000001ca8a8 R15: 00007ffdd786ba50 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5885 Comm: kworker/1:5 Not tainted 6.14.0-rc1-syzkaller-00020-g0de63bb7d919 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: usb_hub_wq hub_event RIP: 0010:kasan_check_range+0x1b8/0x290 mm/kasan/generic.c:189 Code: 4d 01 fb 48 8d 5d 07 48 85 ed 48 0f 49 dd 48 83 e3 f8 48 29 dd 74 12 41 80 3b 00 0f 85 a6 00 00 00 49 ff c3 48 ff cd 75 ee 5b <41> 5c 41 5e 41 5f 5d c3 cc cc cc cc 40 84 ed 75 5f f7 c5 00 ff 00 RSP: 0018:ffffc90000a185f8 EFLAGS: 00000056 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff819b71be RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff942c3840 RBP: 0000000000000000 R08: ffffffff942c3847 R09: 1ffffffff2858708 R10: dffffc0000000000 R11: fffffbfff2858709 R12: dffffc0000000000 R13: ffff88807ca46600 R14: dffffc0000000001 R15: fffffbfff2858709 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020031000 CR3: 0000000042840000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000097 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read include/linux/instrumented.h:68 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] hlock_class kernel/locking/lockdep.c:230 [inline] lookup_chain_cache_add kernel/locking/lockdep.c:3818 [inline] validate_chain+0x11e/0x5920 kernel/locking/lockdep.c:3874 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 debug_object_deactivate+0x158/0x390 lib/debugobjects.c:873 debug_hrtimer_deactivate kernel/time/hrtimer.c:460 [inline] debug_deactivate+0x1b/0x220 kernel/time/hrtimer.c:502 __run_hrtimer kernel/time/hrtimer.c:1769 [inline] __hrtimer_run_queues+0x305/0xd30 kernel/time/hrtimer.c:1865 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1927 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:console_flush_all+0x996/0xeb0 Code: 48 21 c3 0f 85 16 02 00 00 e8 06 8e 20 00 4c 8b 7c 24 10 4d 85 f6 75 07 e8 f7 8d 20 00 eb 06 e8 f0 8d 20 00 fb 48 8b 5c 24 18 <48> 8b 44 24 30 42 80 3c 28 00 74 08 48 89 df e8 06 9f 84 00 4c 8b RSP: 0018:ffffc900043def60 EFLAGS: 00000287 RAX: ffffffff819ecfd0 RBX: ffffffff8f172778 RCX: 0000000000100000 RDX: ffffc90018ee2000 RSI: 0000000000015032 RDI: 0000000000015033 RBP: ffffc900043df110 R08: ffffffff819ecfa7 R09: 1ffffffff2858708 R10: dffffc0000000000 R11: fffffbfff2858709 R12: ffffffff8f172720 R13: dffffc0000000000 R14: 0000000000000200 R15: ffffc900043df160 __console_flush_and_unlock kernel/printk/printk.c:3269 [inline] console_unlock+0x14f/0x3b0 kernel/printk/printk.c:3309 vprintk_emit+0x730/0xa10 kernel/printk/printk.c:2432 dev_vprintk_emit+0x2ae/0x330 drivers/base/core.c:4890 dev_printk_emit+0xdd/0x120 drivers/base/core.c:4901 _dev_info+0x122/0x170 drivers/base/core.c:4959 announce_device drivers/usb/core/hub.c:2365 [inline] usb_new_device+0x579/0x19a0 drivers/usb/core/hub.c:2633 hub_port_connect drivers/usb/core/hub.c:5523 [inline] hub_port_connect_change drivers/usb/core/hub.c:5663 [inline] port_event drivers/usb/core/hub.c:5823 [inline] hub_event+0x2d6d/0x5150 drivers/usb/core/hub.c:5905 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244