rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (0 ticks this GP) idle=e29/1/0x4000000000000000 softirq=180506/180506 fqs=0 (detected by 1, t=10502 jiffies, g=280873, q=222) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5254 Comm: udevd Not tainted 5.17.0-rc3-syzkaller-00247-g83e396641110 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__lock_release kernel/locking/lockdep.c:5323 [inline] RIP: 0010:lock_release+0x202/0x720 kernel/locking/lockdep.c:5659 Code: ed 0f 84 e0 02 00 00 48 8d 4c 24 50 44 89 ea 4c 89 e6 4c 89 ff e8 be 08 ff ff 48 85 c0 48 89 c3 0f 84 85 03 00 00 48 8d 78 24 <48> b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 14 02 48 RSP: 0018:ffffc90000007cf8 EFLAGS: 00000086 RAX: ffff88802aafec60 RBX: ffff88802aafec60 RCX: ffffc90000007d48 RDX: 0000000000000004 RSI: ffff88807060a300 RDI: ffff88802aafec84 RBP: 1ffff92000000fa1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffff88807060a300 R13: 0000000000000001 R14: ffff88802aafec58 R15: ffff88802aafe200 FS: 00007f07f1af6840(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8fe59483a5 CR3: 00000000266d1000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline] _raw_spin_unlock+0x12/0x40 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:638 RIP: 0010:rcu_read_lock_sched_held+0x45/0x70 kernel/rcu/update.c:125 Code: 00 84 c0 74 41 e8 ab ac 00 00 84 c0 74 38 be ff ff ff ff 48 c7 c7 20 10 b8 8b e8 46 4e e8 07 85 c0 75 d3 65 8b 05 cb fc 9f 7e ff ff ff 7f 75 c5 9c 41 5c 49 c1 ec 09 49 83 f4 01 41 83 e4 01 RSP: 0018:ffffc9000ae2fa18 EFLAGS: 00000246 RAX: 0000000080000001 RBX: ffff8881400a2200 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000280 R09: ffff88804651ad40 R10: ffffffff8100742e R11: 0000000000088078 R12: 0000000000000001 R13: 0000000000000dc0 R14: 0000000000000001 R15: ffff88804651ad40 trace_kmem_cache_alloc include/trace/events/kmem.h:54 [inline] kmem_cache_alloc+0x39d/0x560 mm/slab.c:3501 kmem_cache_zalloc include/linux/slab.h:705 [inline] __alloc_file+0x21/0x280 fs/file_table.c:134 alloc_empty_file+0x6d/0x170 fs/file_table.c:183 path_openat+0xe4/0x2940 fs/namei.c:3595 do_filp_open+0x1aa/0x400 fs/namei.c:3636 do_sys_openat2+0x16d/0x4d0 fs/open.c:1214 do_sys_open fs/open.c:1230 [inline] __do_sys_openat fs/open.c:1246 [inline] __se_sys_openat fs/open.c:1241 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1241 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f07f1c4d697 Code: 25 00 00 41 00 3d 00 00 41 00 74 37 64 8b 04 25 18 00 00 00 85 c0 75 5b 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 85 00 00 00 48 83 c4 68 5d 41 5c c3 0f 1f RSP: 002b:00007ffd63202700 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f07f3961890 RCX: 00007f07f1c4d697 RDX: 0000000000080000 RSI: 00007ffd63202838 RDI: 00000000ffffff9c RBP: 00007ffd63202838 R08: 0000000000000008 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000080000 R13: 00007f07f3961890 R14: 0000000000000001 R15: 00007f07f39192c0 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g280873 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=159252 rcu: rcu_preempt kthread starved for 10502 jiffies! g280873 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:28944 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4986 [inline] __schedule+0xab2/0x4db0 kernel/sched/core.c:6295 schedule+0xd2/0x260 kernel/sched/core.c:6368 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1963 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2136 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 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: 5254 Comm: udevd Not tainted 5.17.0-rc3-syzkaller-00247-g83e396641110 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:166 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:200 Code: 48 89 ef 5d e9 a1 58 46 00 5d be 03 00 00 00 e9 a6 d6 66 02 66 0f 1f 44 00 00 48 8b be b0 01 00 00 e8 b4 ff ff ff 31 c0 c3 90 <65> 8b 05 c9 c1 8a 7e 89 c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b RSP: 0018:ffffc90000007e08 EFLAGS: 00000097 RAX: 0000000000000000 RBX: ffff8880b9c2a700 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffff88802aafe200 RDI: 0000000000000003 RBP: ffff88807060a340 R08: 000000000000001f R09: 0000000000000000 R10: ffffffff8166e7b0 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000000 R14: ffff8880b9c2a600 R15: 0000000000000001 FS: 00007f07f1af6840(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8fe59483a5 CR3: 00000000266d1000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: enqueue_hrtimer+0xdf/0x3e0 kernel/time/hrtimer.c:1086 __run_hrtimer kernel/time/hrtimer.c:1702 [inline] __hrtimer_run_queues+0xb02/0xe50 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:638 RIP: 0010:rcu_read_lock_sched_held+0x45/0x70 kernel/rcu/update.c:125 Code: 00 84 c0 74 41 e8 ab ac 00 00 84 c0 74 38 be ff ff ff ff 48 c7 c7 20 10 b8 8b e8 46 4e e8 07 85 c0 75 d3 65 8b 05 cb fc 9f 7e ff ff ff 7f 75 c5 9c 41 5c 49 c1 ec 09 49 83 f4 01 41 83 e4 01 RSP: 0018:ffffc9000ae2fa18 EFLAGS: 00000246 RAX: 0000000080000001 RBX: ffff8881400a2200 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000280 R09: ffff88804651ad40 R10: ffffffff8100742e R11: 0000000000088078 R12: 0000000000000001 R13: 0000000000000dc0 R14: 0000000000000001 R15: ffff88804651ad40 trace_kmem_cache_alloc include/trace/events/kmem.h:54 [inline] kmem_cache_alloc+0x39d/0x560 mm/slab.c:3501 kmem_cache_zalloc include/linux/slab.h:705 [inline] __alloc_file+0x21/0x280 fs/file_table.c:134 alloc_empty_file+0x6d/0x170 fs/file_table.c:183 path_openat+0xe4/0x2940 fs/namei.c:3595 do_filp_open+0x1aa/0x400 fs/namei.c:3636 do_sys_openat2+0x16d/0x4d0 fs/open.c:1214 do_sys_open fs/open.c:1230 [inline] __do_sys_openat fs/open.c:1246 [inline] __se_sys_openat fs/open.c:1241 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1241 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f07f1c4d697 Code: 25 00 00 41 00 3d 00 00 41 00 74 37 64 8b 04 25 18 00 00 00 85 c0 75 5b 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 85 00 00 00 48 83 c4 68 5d 41 5c c3 0f 1f RSP: 002b:00007ffd63202700 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f07f3961890 RCX: 00007f07f1c4d697 RDX: 0000000000080000 RSI: 00007ffd63202838 RDI: 00000000ffffff9c RBP: 00007ffd63202838 R08: 0000000000000008 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000080000 R13: 00007f07f3961890 R14: 0000000000000001 R15: 00007f07f39192c0 ---------------- Code disassembly (best guess): 0: ed in (%dx),%eax 1: 0f 84 e0 02 00 00 je 0x2e7 7: 48 8d 4c 24 50 lea 0x50(%rsp),%rcx c: 44 89 ea mov %r13d,%edx f: 4c 89 e6 mov %r12,%rsi 12: 4c 89 ff mov %r15,%rdi 15: e8 be 08 ff ff callq 0xffff08d8 1a: 48 85 c0 test %rax,%rax 1d: 48 89 c3 mov %rax,%rbx 20: 0f 84 85 03 00 00 je 0x3ab 26: 48 8d 78 24 lea 0x24(%rax),%rdi * 2a: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax <-- trapping instruction 31: fc ff df 34: 48 89 fa mov %rdi,%rdx 37: 48 c1 ea 03 shr $0x3,%rdx 3b: 0f b6 14 02 movzbl (%rdx,%rax,1),%edx 3f: 48 rex.W