rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 0, t=10502 jiffies, g=429601, q=33) rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4295220396-4295209894), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10502 jiffies! g429601 f0x2 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:28696 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4953 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6234 schedule+0xd2/0x260 kernel/sched/core.c:6307 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1966 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2139 kthread+0x405/0x4f0 kernel/kthread.c:327 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: 27407 Comm: syz-executor.1 Not tainted 5.15.0-rc4-next-20211011-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:rdtsc_ordered arch/x86/include/asm/msr.h:234 [inline] RIP: 0010:read_tsc+0x3/0x10 arch/x86/kernel/tsc.c:1095 Code: cc cc cc cc cc cc cc 8b 05 ce c2 64 0c c3 66 0f 1f 84 00 00 00 00 00 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 0f 01 f9 <66> 90 48 c1 e2 20 48 09 d0 c3 0f 1f 00 48 c7 c0 d0 88 8f 8d 48 ba RSP: 0018:ffffc90000dc0eb0 EFLAGS: 00000046 RAX: 000000000e8f029c RBX: ffffffff8b9a4140 RCX: 0000000000000001 RDX: 00000000000005ad RSI: ffffffff8166c168 RDI: ffffffff8b9a4140 RBP: 00000000000894ce R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff8166c15f R11: 0000000000000000 R12: 0000000000000000 R13: 00000000000894ce R14: 0000000000000000 R15: dffffc0000000000 FS: 00007f20b095c700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000382df000 CR4: 00000000003526e0 DR0: 0000000000000005 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: tk_clock_read kernel/time/timekeeping.c:193 [inline] timekeeping_get_delta kernel/time/timekeeping.c:253 [inline] timekeeping_get_ns kernel/time/timekeeping.c:386 [inline] ktime_get_update_offsets_now+0x1e6/0x5c0 kernel/time/timekeeping.c:2300 hrtimer_update_base kernel/time/hrtimer.c:631 [inline] hrtimer_interrupt+0x142/0x790 kernel/time/hrtimer.c:1793 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:pud_alloc include/linux/mm.h:2277 [inline] RIP: 0010:__handle_mm_fault+0x291/0x5120 mm/memory.c:4612 Code: 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 7a 48 00 00 48 8b 2b 31 ff 49 89 ed 49 83 e5 9f 4c 89 ee e8 6f 7a ca ff <4d> 85 ed 0f 84 52 03 00 00 e8 d1 77 ca ff 48 8b 5c 24 10 48 b8 00 RSP: 0018:ffffc90004c17148 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff8880382df000 RCX: 0000000071dae007 RDX: 0000000000000000 RSI: ffff888036291d00 RDI: 0000000000000003 RBP: 0000000071dae067 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff81abfa31 R11: 0000000000000000 R12: 0000000000000014 R13: 0000000071dae007 R14: ffff88808d3dd108 R15: 0000000000000000 handle_mm_fault+0x1c8/0x790 mm/memory.c:4775 faultin_page mm/gup.c:937 [inline] __get_user_pages+0x503/0xf80 mm/gup.c:1158 __get_user_pages_locked mm/gup.c:1343 [inline] get_user_pages_unlocked+0x1b3/0x760 mm/gup.c:2067 hva_to_pfn_slow arch/x86/kvm/../../../virt/kvm/kvm_main.c:2277 [inline] hva_to_pfn+0x1bf/0xdd0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2409 __gfn_to_pfn_memslot+0x229/0x420 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2468 kvm_faultin_pfn+0x50c/0xea0 arch/x86/kvm/mmu/mmu.c:3879 direct_page_fault+0x42c/0x25f0 arch/x86/kvm/mmu/mmu.c:3912 kvm_mmu_do_page_fault arch/x86/kvm/mmu.h:201 [inline] kvm_mmu_page_fault+0x27f/0x1940 arch/x86/kvm/mmu/mmu.c:5196 handle_ept_violation+0x29c/0x6e0 arch/x86/kvm/vmx/vmx.c:5352 __vmx_handle_exit arch/x86/kvm/vmx/vmx.c:6061 [inline] vmx_handle_exit+0x4be/0x1950 arch/x86/kvm/vmx/vmx.c:6078 vcpu_enter_guest+0x2abc/0x4440 arch/x86/kvm/x86.c:9720 vcpu_run arch/x86/kvm/x86.c:9787 [inline] kvm_arch_vcpu_ioctl_run+0x47c/0x1b10 arch/x86/kvm/x86.c:10019 kvm_vcpu_ioctl+0x570/0xf30 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3787 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 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: 0033:0x7f20b33e58d9 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f20b095c188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f20b34e9f60 RCX: 00007f20b33e58d9 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005 RBP: 00007f20b343fcb4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc5f00408f R14: 00007f20b095c300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: cc int3 1: cc int3 2: cc int3 3: cc int3 4: cc int3 5: cc int3 6: cc int3 7: 8b 05 ce c2 64 0c mov 0xc64c2ce(%rip),%eax # 0xc64c2db d: c3 retq e: 66 0f 1f 84 00 00 00 nopw 0x0(%rax,%rax,1) 15: 00 00 17: c3 retq 18: 66 66 2e 0f 1f 84 00 data16 nopw %cs:0x0(%rax,%rax,1) 1f: 00 00 00 00 23: 0f 1f 40 00 nopl 0x0(%rax) 27: 0f 01 f9 rdtscp * 2a: 66 90 xchg %ax,%ax <-- trapping instruction 2c: 48 c1 e2 20 shl $0x20,%rdx 30: 48 09 d0 or %rdx,%rax 33: c3 retq 34: 0f 1f 00 nopl (%rax) 37: 48 c7 c0 d0 88 8f 8d mov $0xffffffff8d8f88d0,%rax 3e: 48 rex.W 3f: ba .byte 0xba