rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (2441 ticks this GP) idle=7c9/1/0x4000000000000000 softirq=215172/215173 fqs=1 (t=10501 jiffies g=403741 q=6582) rcu: rcu_preempt kthread timer wakeup didn't happen for 2442 jiffies! g403741 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=212999 rcu: rcu_preempt kthread starved for 2445 jiffies! g403741 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:28696 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4955 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6236 schedule+0xd3/0x270 kernel/sched/core.c:6315 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1959 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2132 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 25260 Comm: syz-executor.3 Not tainted 5.15.0-rc3-next-20210927-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:debug_smp_processor_id+0x0/0x20 lib/smp_processor_id.c:60 Code: 38 e4 89 4d 8d 86 30 08 00 00 83 e9 01 e8 54 2f be ff 48 8b 74 24 28 48 c7 c7 20 39 e4 89 e8 43 2f be ff e8 6e f9 cc ff eb a2 <0f> 1f 44 00 00 48 c7 c6 60 39 e4 89 48 c7 c7 a0 39 e4 89 e9 a8 fe RSP: 0018:ffffc90000007fa0 EFLAGS: 00000006 RAX: 0000000000010000 RBX: ffff8880b9c27850 RCX: 1ffff11017384f0c RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffff8880b9c27860 RBP: 0000000000000000 R08: ffffffff8ef06018 R09: ffffffff8ef0600f R10: ffffffff8ef06017 R11: 0000000000000001 R12: ffff888157c18000 R13: 00000000000037eb R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c0011a8010 CR3: 0000000071cd5000 CR4: 00000000003506f0 Call Trace: irqtime_account_delta kernel/sched/cputime.c:37 [inline] irqtime_account_irq+0x187/0x2d0 kernel/sched/cputime.c:72 account_hardirq_exit include/linux/vtime.h:159 [inline] __irq_exit_rcu+0x1a/0x180 kernel/softirq.c:634 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 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:check_region_inline mm/kasan/generic.c:169 [inline] RIP: 0010:kasan_check_range+0x9/0x180 mm/kasan/generic.c:189 Code: 47 08 48 c7 c6 80 5a 16 8b 48 8d 50 ff a8 01 48 0f 45 fa e8 19 a1 ec ff 0f 0b 0f 1f 80 00 00 00 00 48 85 f6 0f 84 70 01 00 00 <49> 89 f9 41 54 44 0f b6 c2 49 01 f1 55 53 0f 82 18 01 00 00 48 b8 RSP: 0018:ffffc90042e8f5e8 EFLAGS: 00000202 RAX: dffffc0000000000 RBX: ffff8880b9c3aa08 RCX: ffffffff8161e5b4 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880b9c3aa08 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8d6e6c57 R10: fffffbfff1adcd8a R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000000 R14: ffffffff8b980860 R15: 0000000000000000 instrument_atomic_read include/linux/instrumented.h:71 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:330 [inline] rcu_is_watching+0x54/0xc0 kernel/rcu/tree.c:1121 rcu_read_lock_held_common kernel/rcu/update.c:108 [inline] rcu_read_lock_sched_held+0x1c/0x70 kernel/rcu/update.c:123 trace_lock_acquire include/trace/events/lock.h:13 [inline] lock_acquire+0x442/0x510 kernel/locking/lockdep.c:5596 rcu_lock_acquire include/linux/rcupdate.h:268 [inline] rcu_read_lock include/linux/rcupdate.h:694 [inline] folio_memcg_lock+0x3a/0x3e0 mm/memcontrol.c:1979 page_remove_rmap+0x25/0x1480 mm/rmap.c:1348 zap_pte_range mm/memory.c:1357 [inline] zap_pmd_range mm/memory.c:1467 [inline] zap_pud_range mm/memory.c:1496 [inline] zap_p4d_range mm/memory.c:1517 [inline] unmap_page_range+0xf0e/0x29f0 mm/memory.c:1538 unmap_single_vma+0x198/0x310 mm/memory.c:1583 unmap_vmas+0x16d/0x2f0 mm/memory.c:1615 exit_mmap+0x1d0/0x630 mm/mmap.c:3171 __mmput+0x122/0x4b0 kernel/fork.c:1166 mmput+0x58/0x60 kernel/fork.c:1187 exit_mm kernel/exit.c:501 [inline] do_exit+0xabc/0x2a30 kernel/exit.c:812 do_group_exit+0x125/0x310 kernel/exit.c:922 get_signal+0x47f/0x2160 kernel/signal.c:2868 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:863 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f384b6fd709 Code: Unable to access opcode bytes at RIP 0x7f384b6fd6df. RSP: 002b:00007f3848c74218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f384b801f68 RCX: 00007f384b6fd709 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f384b801f68 RBP: 00007f384b801f60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f384b801f6c R13: 00007ffd2ec7ec1f R14: 00007f3848c74300 R15: 0000000000022000 NMI backtrace for cpu 1 CPU: 1 PID: 5767 Comm: syz-executor.3 Not tainted 5.15.0-rc3-next-20210927-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:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 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:3882 [inline] rcu_sched_clock_irq.cold+0x9d/0x746 kernel/rcu/tree.c:2601 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:1428 __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+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:bytes_is_nonzero mm/kasan/generic.c:85 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0xde/0x180 mm/kasan/generic.c:189 Code: 74 f2 48 89 c2 b8 01 00 00 00 48 85 d2 75 56 5b 5d 41 5c c3 48 85 d2 74 5e 48 01 ea eb 09 48 83 c0 01 48 39 d0 74 50 80 38 00 <74> f2 eb d4 41 bc 08 00 00 00 48 89 ea 45 29 dc 4d 8d 1c 2c eb 0c RSP: 0018:ffffc900418c7758 EFLAGS: 00000246 RAX: fffff94000427d60 RBX: fffff94000427d61 RCX: ffffffff81c1ccdb RDX: fffff94000427d61 RSI: 0000000000000008 RDI: ffffea000213eb00 RBP: fffff94000427d60 R08: 0000000000000000 R09: ffffea000213eb07 R10: fffff94000427d60 R11: 0000000000000000 R12: ffffea000213eb00 R13: ffff88815306ed90 R14: dffffc0000000000 R15: 00007f3849fb3000 instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] folio_test_slab include/linux/page-flags.h:422 [inline] __folio_memcg include/linux/memcontrol.h:400 [inline] folio_memcg+0x7b/0x190 include/linux/memcontrol.h:452 folio_memcg_unlock mm/memcontrol.c:2042 [inline] unlock_page_memcg+0x3d/0x150 mm/memcontrol.c:2047 zap_pte_range mm/memory.c:1357 [inline] zap_pmd_range mm/memory.c:1467 [inline] zap_pud_range mm/memory.c:1496 [inline] zap_p4d_range mm/memory.c:1517 [inline] unmap_page_range+0xf0e/0x29f0 mm/memory.c:1538 unmap_single_vma+0x198/0x310 mm/memory.c:1583 unmap_vmas+0x16d/0x2f0 mm/memory.c:1615 exit_mmap+0x1d0/0x630 mm/mmap.c:3171 __mmput+0x122/0x4b0 kernel/fork.c:1166 mmput+0x58/0x60 kernel/fork.c:1187 exit_mm kernel/exit.c:501 [inline] do_exit+0xabc/0x2a30 kernel/exit.c:812 do_group_exit+0x125/0x310 kernel/exit.c:922 get_signal+0x47f/0x2160 kernel/signal.c:2868 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:863 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f384b6fd709 Code: Unable to access opcode bytes at RIP 0x7f384b6fd6df. RSP: 002b:00007f3848c74218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f384b801f68 RCX: 00007f384b6fd709 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f384b801f68 RBP: 00007f384b801f60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f384b801f6c R13: 00007ffd2ec7ec1f R14: 00007f3848c74300 R15: 0000000000022000 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: e4 89 in $0x89,%al 2: 4d 8d 86 30 08 00 00 lea 0x830(%r14),%r8 9: 83 e9 01 sub $0x1,%ecx c: e8 54 2f be ff callq 0xffbe2f65 11: 48 8b 74 24 28 mov 0x28(%rsp),%rsi 16: 48 c7 c7 20 39 e4 89 mov $0xffffffff89e43920,%rdi 1d: e8 43 2f be ff callq 0xffbe2f65 22: e8 6e f9 cc ff callq 0xffccf995 27: eb a2 jmp 0xffffffcb * 29: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) <-- trapping instruction 2e: 48 c7 c6 60 39 e4 89 mov $0xffffffff89e43960,%rsi 35: 48 c7 c7 a0 39 e4 89 mov $0xffffffff89e439a0,%rdi 3c: e9 .byte 0xe9 3d: a8 fe test $0xfe,%al