rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (6519 ticks this GP) idle=2b1/1/0x4000000000000000 softirq=18869/18870 fqs=17 (t=10500 jiffies g=21165 q=742) rcu: rcu_preempt kthread starved for 9160 jiffies! g21165 f0x0 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:27536 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6287 schedule+0xd3/0x270 kernel/sched/core.c:6366 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x800 kernel/rcu/tree.c:1957 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2130 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 0 CPU: 0 PID: 14394 Comm: syz-executor.0 Not tainted 5.14.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_check_gp_kthread_starvation.cold+0x1fb/0x200 kernel/rcu/tree_stall.h:481 print_cpu_stall kernel/rcu/tree_stall.h:625 [inline] check_cpu_stall kernel/rcu/tree_stall.h:711 [inline] rcu_pending kernel/rcu/tree.c:3880 [inline] rcu_sched_clock_irq.cold+0x98/0x746 kernel/rcu/tree.c:2599 update_process_times+0x16d/0x200 kernel/time/timer.c:1785 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1421 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x1c0/0xe50 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+0x40/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:163 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:197 Code: 01 f0 4d 89 03 e9 63 fd ff ff b9 ff ff ff ff ba 08 00 00 00 4d 8b 03 48 0f bd ca 49 8b 45 00 48 63 c9 e9 64 ff ff ff 0f 1f 00 <65> 8b 05 e9 cf 8b 7e 89 c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b RSP: 0018:ffffc90000007c48 EFLAGS: 00000206 RAX: 0000000000000000 RBX: ffff8880887b4270 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff888026a88000 RDI: 0000000000000003 RBP: 000000000001c9c3 R08: 000000000001c9c3 R09: 0000000000000001 R10: ffffffff874f3523 R11: 0000000000000000 R12: fffffff0a3da8872 R13: ffff88802ce85b00 R14: 0000000000000000 R15: 0000000000000001 pie_calculate_probability+0x4e5/0x7c0 net/sched/sch_pie.c:412 fq_pie_timer+0x170/0x2a0 net/sched/sch_fq_pie.c:383 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x675/0xa20 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:636 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:preempt_schedule_irq+0x49/0x90 kernel/sched/core.c:6687 Code: 55 53 65 48 8b 1c 25 40 f0 01 00 48 89 dd 48 c1 ed 03 48 01 c5 bf 01 00 00 00 e8 62 8b 1b f8 e8 3d 26 48 f8 fb bf 01 00 00 00 d2 cd ff ff 9c 58 fa f6 c4 02 75 27 bf 01 00 00 00 e8 60 7a 1b RSP: 0018:ffffc9000263f8d8 EFLAGS: 00000246 RAX: 0000000000000007 RBX: ffff888026a88000 RCX: 1ffffffff1adbb3d RDX: 0000000000000000 RSI: ffffffff817c4961 RDI: 0000000000000001 RBP: ffffed1004d51000 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff817c4948 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 irqentry_exit+0x31/0x80 kernel/entry/common.c:427 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:_compound_head include/linux/page-flags.h:188 [inline] RIP: 0010:virt_to_head_page include/linux/mm.h:901 [inline] RIP: 0010:qlink_to_cache mm/kasan/quarantine.c:120 [inline] RIP: 0010:qlist_free_all+0x89/0xc0 mm/kasan/quarantine.c:162 Code: 4c 89 fe 48 85 ed 48 89 ef 75 cb 48 89 f7 48 89 34 24 e8 ea c2 77 ff 48 8b 34 24 48 c1 e8 0c 48 c1 e0 06 4c 01 f0 48 8b 50 08 <48> 8d 4a ff 83 e2 01 48 0f 45 c1 48 8b 78 18 eb 9b 49 c7 45 08 00 RSP: 0018:ffffc9000263f9a0 EFLAGS: 00000282 RAX: ffffea00006d9740 RBX: ffff888020b6b900 RCX: ffffc90001781000 RDX: ffffea00006d9701 RSI: ffff88801b65da40 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000030 R10: ffffffff81349eca R11: 000000000000003f R12: dffffc0000000000 R13: ffffc9000263f9d8 R14: ffffea0000000000 R15: ffff88801b65da40 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272 __kasan_slab_alloc+0x95/0xb0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] slab_alloc_node mm/slub.c:2959 [inline] slab_alloc mm/slub.c:2967 [inline] kmem_cache_alloc+0x285/0x4a0 mm/slub.c:2972 kmem_cache_zalloc include/linux/slab.h:711 [inline] __alloc_file+0x21/0x280 fs/file_table.c:101 alloc_empty_file+0x6d/0x170 fs/file_table.c:150 path_openat+0xe4/0x2740 fs/namei.c:3545 do_filp_open+0x1aa/0x400 fs/namei.c:3586 do_sys_openat2+0x16d/0x4d0 fs/open.c:1200 do_sys_open fs/open.c:1216 [inline] __do_sys_openat fs/open.c:1232 [inline] __se_sys_openat fs/open.c:1227 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1227 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: 0033:0x4665f9 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:00007f4fd1196188 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665f9 RDX: 0000000000000000 RSI: 0000000020000000 RDI: ffffffffffffffff RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007ffd58e9bbdf R14: 00007f4fd1196300 R15: 0000000000022000 NMI backtrace for cpu 0 CPU: 0 PID: 14394 Comm: syz-executor.0 Not tainted 5.14.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x25e/0x3f0 kernel/rcu/tree_stall.h:343 print_cpu_stall kernel/rcu/tree_stall.h:627 [inline] check_cpu_stall kernel/rcu/tree_stall.h:711 [inline] rcu_pending kernel/rcu/tree.c:3880 [inline] rcu_sched_clock_irq.cold+0x9d/0x746 kernel/rcu/tree.c:2599 update_process_times+0x16d/0x200 kernel/time/timer.c:1785 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1421 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x1c0/0xe50 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+0x40/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:163 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:197 Code: 01 f0 4d 89 03 e9 63 fd ff ff b9 ff ff ff ff ba 08 00 00 00 4d 8b 03 48 0f bd ca 49 8b 45 00 48 63 c9 e9 64 ff ff ff 0f 1f 00 <65> 8b 05 e9 cf 8b 7e 89 c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b RSP: 0018:ffffc90000007c48 EFLAGS: 00000206 RAX: 0000000000000000 RBX: ffff8880887b4270 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff888026a88000 RDI: 0000000000000003 RBP: 000000000001c9c3 R08: 000000000001c9c3 R09: 0000000000000001 R10: ffffffff874f3523 R11: 0000000000000000 R12: fffffff0a3da8872 R13: ffff88802ce85b00 R14: 0000000000000000 R15: 0000000000000001 pie_calculate_probability+0x4e5/0x7c0 net/sched/sch_pie.c:412 fq_pie_timer+0x170/0x2a0 net/sched/sch_fq_pie.c:383 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x675/0xa20 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:636 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:preempt_schedule_irq+0x49/0x90 kernel/sched/core.c:6687 Code: 55 53 65 48 8b 1c 25 40 f0 01 00 48 89 dd 48 c1 ed 03 48 01 c5 bf 01 00 00 00 e8 62 8b 1b f8 e8 3d 26 48 f8 fb bf 01 00 00 00 d2 cd ff ff 9c 58 fa f6 c4 02 75 27 bf 01 00 00 00 e8 60 7a 1b RSP: 0018:ffffc9000263f8d8 EFLAGS: 00000246 RAX: 0000000000000007 RBX: ffff888026a88000 RCX: 1ffffffff1adbb3d RDX: 0000000000000000 RSI: ffffffff817c4961 RDI: 0000000000000001 RBP: ffffed1004d51000 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff817c4948 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 irqentry_exit+0x31/0x80 kernel/entry/common.c:427 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:_compound_head include/linux/page-flags.h:188 [inline] RIP: 0010:virt_to_head_page include/linux/mm.h:901 [inline] RIP: 0010:qlink_to_cache mm/kasan/quarantine.c:120 [inline] RIP: 0010:qlist_free_all+0x89/0xc0 mm/kasan/quarantine.c:162 Code: 4c 89 fe 48 85 ed 48 89 ef 75 cb 48 89 f7 48 89 34 24 e8 ea c2 77 ff 48 8b 34 24 48 c1 e8 0c 48 c1 e0 06 4c 01 f0 48 8b 50 08 <48> 8d 4a ff 83 e2 01 48 0f 45 c1 48 8b 78 18 eb 9b 49 c7 45 08 00 RSP: 0018:ffffc9000263f9a0 EFLAGS: 00000282 RAX: ffffea00006d9740 RBX: ffff888020b6b900 RCX: ffffc90001781000 RDX: ffffea00006d9701 RSI: ffff88801b65da40 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000030 R10: ffffffff81349eca R11: 000000000000003f R12: dffffc0000000000 R13: ffffc9000263f9d8 R14: ffffea0000000000 R15: ffff88801b65da40 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272 __kasan_slab_alloc+0x95/0xb0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] slab_alloc_node mm/slub.c:2959 [inline] slab_alloc mm/slub.c:2967 [inline] kmem_cache_alloc+0x285/0x4a0 mm/slub.c:2972 kmem_cache_zalloc include/linux/slab.h:711 [inline] __alloc_file+0x21/0x280 fs/file_table.c:101 alloc_empty_file+0x6d/0x170 fs/file_table.c:150 path_openat+0xe4/0x2740 fs/namei.c:3545 do_filp_open+0x1aa/0x400 fs/namei.c:3586 do_sys_openat2+0x16d/0x4d0 fs/open.c:1200 do_sys_open fs/open.c:1216 [inline] __do_sys_openat fs/open.c:1232 [inline] __se_sys_openat fs/open.c:1227 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1227 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: 0033:0x4665f9 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:00007f4fd1196188 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665f9 RDX: 0000000000000000 RSI: 0000000020000000 RDI: ffffffffffffffff RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007ffd58e9bbdf R14: 00007f4fd1196300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: 01 f0 add %esi,%eax 2: 4d 89 03 mov %r8,(%r11) 5: e9 63 fd ff ff jmpq 0xfffffd6d a: b9 ff ff ff ff mov $0xffffffff,%ecx f: ba 08 00 00 00 mov $0x8,%edx 14: 4d 8b 03 mov (%r11),%r8 17: 48 0f bd ca bsr %rdx,%rcx 1b: 49 8b 45 00 mov 0x0(%r13),%rax 1f: 48 63 c9 movslq %ecx,%rcx 22: e9 64 ff ff ff jmpq 0xffffff8b 27: 0f 1f 00 nopl (%rax) * 2a: 65 8b 05 e9 cf 8b 7e mov %gs:0x7e8bcfe9(%rip),%eax # 0x7e8bd01a <-- trapping instruction 31: 89 c1 mov %eax,%ecx 33: 48 8b 34 24 mov (%rsp),%rsi 37: 81 e1 00 01 00 00 and $0x100,%ecx 3d: 65 gs 3e: 48 rex.W 3f: 8b .byte 0x8b