rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (0 ticks this GP) idle=ccd/1/0x4000000000000000 softirq=90333/90333 fqs=0 (detected by 0, t=10502 jiffies, g=132109, q=66) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 19882 Comm: syz-executor.4 Not tainted 5.17.0-rc2-syzkaller-00167-gdcb85f85fa6f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:mark_lock+0x96/0x17b0 kernel/locking/lockdep.c:4577 Code: 65 48 8b 04 25 28 00 00 00 48 89 84 24 10 01 00 00 31 c0 41 83 fc 09 0f 87 3f 01 00 00 41 83 fc 08 49 89 f5 0f 84 f6 00 00 00 01 00 00 00 44 89 e1 d3 e5 48 63 ed 4d 8d 7d 20 48 b8 00 00 00 RSP: 0018:ffffc90000dc0aa8 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 1ffff920001b815c RCX: 1ffffffff1ff8456 RDX: 0000000000000002 RSI: ffff88805cac4528 RDI: ffff88805cac454a RBP: ffff88805cac454a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000008 R13: ffff88805cac4528 R14: 0000000000000005 R15: 0000000000000005 FS: 000055555592d400(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f45491a43a5 CR3: 0000000048422000 CR4: 0000000000350ee0 Call Trace: mark_usage kernel/locking/lockdep.c:4526 [inline] __lock_acquire+0x8a7/0x5470 kernel/locking/lockdep.c:4981 lock_acquire kernel/locking/lockdep.c:5639 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5604 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0x32/0x50 kernel/locking/spinlock.c:170 __run_hrtimer kernel/time/hrtimer.c:1689 [inline] __hrtimer_run_queues+0x243/0xe50 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:_compound_head include/linux/page-flags.h:197 [inline] RIP: 0010:get_page include/linux/mm.h:1166 [inline] RIP: 0010:copy_present_pte mm/memory.c:958 [inline] RIP: 0010:copy_pte_range mm/memory.c:1074 [inline] RIP: 0010:copy_pmd_range mm/memory.c:1160 [inline] RIP: 0010:copy_pud_range mm/memory.c:1197 [inline] RIP: 0010:copy_p4d_range mm/memory.c:1221 [inline] RIP: 0010:copy_page_range+0xe23/0x42b0 mm/memory.c:1294 Code: 20 48 89 44 24 60 0f 84 b2 05 00 00 e8 06 55 c9 ff 48 8b 44 24 60 48 c1 e8 03 42 80 3c 28 00 0f 85 f0 2b 00 00 4d 8b 7c 24 08 <31> ff 4d 89 fe 41 83 e6 01 4c 89 f6 e8 6c 57 c9 ff 4d 85 f6 0f 85 RSP: 0018:ffffc90004b6f800 EFLAGS: 00000246 RAX: 1ffffd40003caf91 RBX: 80000000795f2007 RCX: 0000000000000000 RDX: ffff88805cac3a00 RSI: ffffffff81af238a RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000020 R09: ffff88807fa46243 R10: ffffffff81af2371 R11: 0000000000000000 R12: ffffea0001e57c80 R13: dffffc0000000000 R14: 0000000000000028 R15: 0000000000000000 dup_mmap kernel/fork.c:612 [inline] dup_mm+0xa4e/0x13e0 kernel/fork.c:1451 copy_mm kernel/fork.c:1503 [inline] copy_process+0x71f8/0x7300 kernel/fork.c:2164 kernel_clone+0xe7/0xab0 kernel/fork.c:2555 __do_sys_clone+0xc8/0x110 kernel/fork.c:2672 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: 0033:0x7f454815664b Code: ed 0f 85 60 01 00 00 64 4c 8b 0c 25 10 00 00 00 45 31 c0 4d 8d 91 d0 02 00 00 31 d2 31 f6 bf 11 00 20 01 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 89 00 00 00 41 89 c5 85 c0 0f 85 90 00 00 RSP: 002b:00007fff67859050 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f454815664b RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 000055555592d400 R10: 000055555592d6d0 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000001 R15: 00007fff67859130 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g132109 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=53919 rcu: rcu_preempt kthread starved for 10502 jiffies! g132109 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:28576 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 19882 Comm: syz-executor.4 Not tainted 5.17.0-rc2-syzkaller-00167-gdcb85f85fa6f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__lock_release kernel/locking/lockdep.c:5325 [inline] RIP: 0010:lock_release+0x250/0x720 kernel/locking/lockdep.c:5659 Code: 0f 85 94 04 00 00 8b 73 24 85 f6 0f 85 28 04 00 00 48 8d 7b 22 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 14 02 <48> 89 f8 83 e0 07 83 c0 01 38 d0 7c 08 84 d2 0f 85 47 04 00 00 66 RSP: 0018:ffffc90000dc0d60 EFLAGS: 00000016 RAX: dffffc0000000000 RBX: ffff88805cac4528 RCX: ffffc90000dc0db0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88805cac454a RBP: 1ffff920001b81ae R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880b9d2a618 R13: 0000000000000006 R14: ffff88805cac4458 R15: ffff88805cac3a00 FS: 000055555592d400(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f45491a43a5 CR3: 0000000048422000 CR4: 0000000000350ee0 Call Trace: __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline] _raw_spin_unlock_irqrestore+0x16/0x70 kernel/locking/spinlock.c:194 __run_hrtimer kernel/time/hrtimer.c:1681 [inline] __hrtimer_run_queues+0x51a/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:_compound_head include/linux/page-flags.h:197 [inline] RIP: 0010:get_page include/linux/mm.h:1166 [inline] RIP: 0010:copy_present_pte mm/memory.c:958 [inline] RIP: 0010:copy_pte_range mm/memory.c:1074 [inline] RIP: 0010:copy_pmd_range mm/memory.c:1160 [inline] RIP: 0010:copy_pud_range mm/memory.c:1197 [inline] RIP: 0010:copy_p4d_range mm/memory.c:1221 [inline] RIP: 0010:copy_page_range+0xe23/0x42b0 mm/memory.c:1294 Code: 20 48 89 44 24 60 0f 84 b2 05 00 00 e8 06 55 c9 ff 48 8b 44 24 60 48 c1 e8 03 42 80 3c 28 00 0f 85 f0 2b 00 00 4d 8b 7c 24 08 <31> ff 4d 89 fe 41 83 e6 01 4c 89 f6 e8 6c 57 c9 ff 4d 85 f6 0f 85 RSP: 0018:ffffc90004b6f800 EFLAGS: 00000246 RAX: 1ffffd40003caf91 RBX: 80000000795f2007 RCX: 0000000000000000 RDX: ffff88805cac3a00 RSI: ffffffff81af238a RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000020 R09: ffff88807fa46243 R10: ffffffff81af2371 R11: 0000000000000000 R12: ffffea0001e57c80 R13: dffffc0000000000 R14: 0000000000000028 R15: 0000000000000000 dup_mmap kernel/fork.c:612 [inline] dup_mm+0xa4e/0x13e0 kernel/fork.c:1451 copy_mm kernel/fork.c:1503 [inline] copy_process+0x71f8/0x7300 kernel/fork.c:2164 kernel_clone+0xe7/0xab0 kernel/fork.c:2555 __do_sys_clone+0xc8/0x110 kernel/fork.c:2672 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: 0033:0x7f454815664b Code: ed 0f 85 60 01 00 00 64 4c 8b 0c 25 10 00 00 00 45 31 c0 4d 8d 91 d0 02 00 00 31 d2 31 f6 bf 11 00 20 01 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 89 00 00 00 41 89 c5 85 c0 0f 85 90 00 00 RSP: 002b:00007fff67859050 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f454815664b RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 000055555592d400 R10: 000055555592d6d0 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000001 R15: 00007fff67859130 vkms_vblank_simulate: vblank timer overrun ---------------- Code disassembly (best guess): 0: 65 48 8b 04 25 28 00 mov %gs:0x28,%rax 7: 00 00 9: 48 89 84 24 10 01 00 mov %rax,0x110(%rsp) 10: 00 11: 31 c0 xor %eax,%eax 13: 41 83 fc 09 cmp $0x9,%r12d 17: 0f 87 3f 01 00 00 ja 0x15c 1d: 41 83 fc 08 cmp $0x8,%r12d 21: 49 89 f5 mov %rsi,%r13 24: 0f 84 f6 00 00 00 je 0x120 * 2a: bd 01 00 00 00 mov $0x1,%ebp <-- trapping instruction 2f: 44 89 e1 mov %r12d,%ecx 32: d3 e5 shl %cl,%ebp 34: 48 63 ed movslq %ebp,%rbp 37: 4d 8d 7d 20 lea 0x20(%r13),%r15 3b: 48 rex.W 3c: b8 .byte 0xb8 3d: 00 00 add %al,(%rax)