rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 ticks this GP) idle=387/1/0x4000000000000000 softirq=281692/281692 fqs=0 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P28992/1:b..l (detected by 1, t=10502 jiffies, g=427993, q=139) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 29013 Comm: syz-executor.0 Not tainted 5.17.0-syzkaller-13993-g88e6c0207623 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:advance_sched+0x96/0x9a0 net/sched/sch_taprio.c:715 Code: ed 0f 84 fd 04 00 00 e8 78 24 06 fa 48 8d 43 e8 48 89 c2 48 89 44 24 08 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 <0f> 85 2a 08 00 00 be ff ff ff ff 4c 89 e7 4c 8b 6b e8 e8 13 f2 eb RSP: 0018:ffffc90000007dd0 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffff888076502b40 RCX: 0000000000000000 RDX: 1ffff1100eca0565 RSI: ffffffff877278a8 RDI: 0000000000000003 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000003 R10: ffffffff8772789b R11: 0000000000000001 R12: ffff888076502b00 R13: ffff8880b9c2a700 R14: ffff8880b9c2a600 R15: ffffffff87727830 FS: 00007f5fc4552700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5fc359d090 CR3: 0000000063156000 CR4: 0000000000350ef0 Call Trace: __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x609/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:lock_acquire+0x1ef/0x510 kernel/locking/lockdep.c:5609 Code: 12 a5 7e 83 f8 01 0f 85 b4 02 00 00 9c 58 f6 c4 02 0f 85 9f 02 00 00 48 83 7c 24 08 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc90001ccfda0 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff92000399fb6 RCX: 8344e4648cc44188 RDX: 1ffff1100ade34eb RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff9002a907 R10: fffffbfff2005520 R11: 0000000000000001 R12: 0000000000000002 R13: 0000000000000000 R14: ffffffff8bd81f60 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:268 [inline] rcu_read_lock include/linux/rcupdate.h:694 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2021 [inline] bpf_trace_run2+0xaa/0x340 kernel/trace/bpf_trace.c:2059 trace_sys_exit include/trace/events/syscalls.h:44 [inline] syscall_exit_work kernel/entry/common.c:259 [inline] syscall_exit_to_user_mode_prepare+0x18b/0x230 kernel/entry/common.c:290 __syscall_exit_to_user_mode_work kernel/entry/common.c:295 [inline] syscall_exit_to_user_mode+0x9/0x60 kernel/entry/common.c:308 do_syscall_64+0x42/0x80 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f5fc3489049 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f5fc4552168 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3 RAX: 0000000000000000 RBX: 00007f5fc359bf60 RCX: 00007f5fc3489049 RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000000 RBP: 00007f5fc34e308d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd6b22f58f R14: 00007f5fc4552300 R15: 0000000000022000 task:syz-executor.1 state:R running task stack:29152 pid:28992 ppid: 11642 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5073 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6382 preempt_schedule_irq+0x4e/0x90 kernel/sched/core.c:6690 irqentry_exit+0x31/0x80 kernel/entry/common.c:442 asm_sysvec_reschedule_ipi+0x12/0x20 arch/x86/include/asm/idtentry.h:650 RIP: 0010:lock_acquire+0x1ef/0x510 kernel/locking/lockdep.c:5609 Code: 12 a5 7e 83 f8 01 0f 85 b4 02 00 00 9c 58 f6 c4 02 0f 85 9f 02 00 00 48 83 7c 24 08 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc9000328f9a0 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff92000651f36 RCX: 128e7cbf2d2888ad RDX: 1ffff1100e91514b RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff9002a907 R10: fffffbfff2005520 R11: 0000000000000001 R12: 0000000000000002 R13: 0000000000000000 R14: ffffffff8bd81f60 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:268 [inline] rcu_read_lock include/linux/rcupdate.h:694 [inline] count_memcg_event_mm.part.0+0x38/0x2d0 include/linux/memcontrol.h:1071 count_memcg_event_mm include/linux/memcontrol.h:578 [inline] handle_mm_fault+0xcf/0x790 mm/memory.c:4841 do_user_addr_fault+0x489/0x11c0 arch/x86/mm/fault.c:1397 handle_page_fault arch/x86/mm/fault.c:1484 [inline] exc_page_fault+0x9e/0x180 arch/x86/mm/fault.c:1540 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:570 RIP: 0010:copy_user_generic_string+0x2c/0x40 arch/x86/lib/copy_user_64.S:163 Code: cb 83 fa 08 72 27 89 f9 83 e1 07 74 15 83 e9 08 f7 d9 29 ca 8a 06 88 07 48 ff c6 48 ff c7 ff c9 75 f2 89 d1 c1 e9 03 83 e2 07 48 a5 89 d1 f3 a4 31 c0 0f 01 ca c3 8d 0c ca 89 ca eb 20 0f 01 RSP: 0018:ffffc9000328fc40 EFLAGS: 00050246 RAX: 0000000000000001 RBX: 0000000000001000 RCX: 0000000000000200 RDX: 0000000000000000 RSI: 000000002019e000 RDI: ffff888055a08000 RBP: ffff888055a08000 R08: 0000000000000001 R09: ffff888055a08fff R10: ffffed100ab411ff R11: 0000000000000000 R12: 00007fffffffe000 R13: 000000002019e000 R14: dffffc0000000000 R15: 000000002019e000 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:52 [inline] _copy_from_user+0x137/0x170 lib/usercopy.c:16 copy_from_user include/linux/uaccess.h:152 [inline] snd_rawmidi_kernel_write1+0x361/0x870 sound/core/rawmidi.c:1486 snd_rawmidi_write+0x273/0xb90 sound/core/rawmidi.c:1555 vfs_write+0x269/0xac0 fs/read_write.c:589 ksys_write+0x1e8/0x250 fs/read_write.c:644 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fea94689049 RSP: 002b:00007fea935fe168 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fea9479bf60 RCX: 00007fea94689049 RDX: 00000000fffffd2c RSI: 0000000020000000 RDI: 0000000000000004 RBP: 00007fea946e308d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff357a9baf R14: 00007fea935fe300 R15: 0000000000022000 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g427993 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=163488 rcu: rcu_preempt kthread starved for 10502 jiffies! g427993 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:28728 pid: 16 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5073 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6382 schedule+0xd2/0x1f0 kernel/sched/core.c:6454 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1971 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2144 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 29013 Comm: syz-executor.0 Not tainted 5.17.0-syzkaller-13993-g88e6c0207623 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:debug_spin_unlock kernel/locking/spinlock_debug.c:100 [inline] RIP: 0010:do_raw_spin_unlock+0x7d/0x230 kernel/locking/spinlock_debug.c:140 Code: 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 0f b6 14 02 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 6a 01 00 00 8b 45 00 <85> c0 0f 84 f3 00 00 00 4c 8d 6d 10 48 b8 00 00 00 00 00 fc ff df RSP: 0018:ffffc90000007da0 EFLAGS: 00000046 RAX: 0000000000000001 RBX: ffff888076502b40 RCX: ffffffff815dde90 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff888076502ae8 RBP: ffff888076502ae8 R08: 0000000000000000 R09: ffff888076502aeb R10: ffffed100eca055d R11: 0000000000000001 R12: ffff8880587c8b80 R13: 18260272b04c04e5 R14: ffff8880587c8ba0 R15: 18260272b04c04e5 FS: 00007f5fc4552700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5fc359d090 CR3: 0000000063156000 CR4: 0000000000350ef0 Call Trace: __raw_spin_unlock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_unlock+0x1a/0x40 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:389 [inline] advance_sched+0x435/0x9a0 net/sched/sch_taprio.c:763 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x609/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:lock_acquire+0x1ef/0x510 kernel/locking/lockdep.c:5609 Code: 12 a5 7e 83 f8 01 0f 85 b4 02 00 00 9c 58 f6 c4 02 0f 85 9f 02 00 00 48 83 7c 24 08 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc90001ccfda0 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff92000399fb6 RCX: 8344e4648cc44188 RDX: 1ffff1100ade34eb RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff9002a907 R10: fffffbfff2005520 R11: 0000000000000001 R12: 0000000000000002 R13: 0000000000000000 R14: ffffffff8bd81f60 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:268 [inline] rcu_read_lock include/linux/rcupdate.h:694 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2021 [inline] bpf_trace_run2+0xaa/0x340 kernel/trace/bpf_trace.c:2059 trace_sys_exit include/trace/events/syscalls.h:44 [inline] syscall_exit_work kernel/entry/common.c:259 [inline] syscall_exit_to_user_mode_prepare+0x18b/0x230 kernel/entry/common.c:290 __syscall_exit_to_user_mode_work kernel/entry/common.c:295 [inline] syscall_exit_to_user_mode+0x9/0x60 kernel/entry/common.c:308 do_syscall_64+0x42/0x80 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f5fc3489049 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f5fc4552168 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3 RAX: 0000000000000000 RBX: 00007f5fc359bf60 RCX: 00007f5fc3489049 RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000000 RBP: 00007f5fc34e308d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd6b22f58f R14: 00007f5fc4552300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: ed in (%dx),%eax 1: 0f 84 fd 04 00 00 je 0x504 7: e8 78 24 06 fa callq 0xfa062484 c: 48 8d 43 e8 lea -0x18(%rbx),%rax 10: 48 89 c2 mov %rax,%rdx 13: 48 89 44 24 08 mov %rax,0x8(%rsp) 18: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 1f: fc ff df 22: 48 c1 ea 03 shr $0x3,%rdx 26: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) * 2a: 0f 85 2a 08 00 00 jne 0x85a <-- trapping instruction 30: be ff ff ff ff mov $0xffffffff,%esi 35: 4c 89 e7 mov %r12,%rdi 38: 4c 8b 6b e8 mov -0x18(%rbx),%r13 3c: e8 .byte 0xe8 3d: 13 f2 adc %edx,%esi 3f: eb .byte 0xeb