rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6843/1:b..l (detected by 1, t=10503 jiffies, g=453997, q=6987) task:syz-executor.4 state:R running task stack:23920 pid: 6843 ppid: 1 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6253 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6419 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35 __raw_read_unlock include/linux/rwlock_api_smp.h:225 [inline] _raw_read_unlock+0x36/0x40 kernel/locking/spinlock.c:260 zap_pid_ns_processes+0x271/0x660 kernel/pid_namespace.c:207 find_child_reaper kernel/exit.c:548 [inline] forget_original_parent kernel/exit.c:637 [inline] exit_notify kernel/exit.c:674 [inline] do_exit+0x243d/0x2b40 kernel/exit.c:852 do_group_exit+0x125/0x310 kernel/exit.c:929 __do_sys_exit_group kernel/exit.c:940 [inline] __se_sys_exit_group kernel/exit.c:938 [inline] __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:938 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: 0033:0x7f3d4bb4cae9 RSP: 002b:00007f3d4c193c58 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f3d4bb4cae9 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000043 RBP: 0000000000000000 R08: 000000000000002e R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3d4bba6fd3 R13: 000000000000000b R14: 0000000000000001 R15: 00007f3d4c193e40 rcu: rcu_preempt kthread timer wakeup didn't happen for 9383 jiffies! g453997 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=246303 rcu: rcu_preempt kthread starved for 9386 jiffies! g453997 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:28688 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6253 schedule+0xd2/0x260 kernel/sched/core.c:6326 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1955 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2128 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: 11481 Comm: syz-executor.0 Not tainted 5.16.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:debug_object_deactivate+0x2/0x300 lib/debugobjects.c:724 Code: ff ff 48 89 cf 48 89 54 24 18 48 89 4c 24 10 e8 74 8f df fd 48 8b 54 24 18 48 8b 4c 24 10 e9 e2 f4 ff ff 0f 1f 44 00 00 41 57 <41> 56 41 55 41 54 49 bc 00 00 00 00 00 fc ff df 55 53 48 81 ec b0 RSP: 0018:ffffc90000007e30 EFLAGS: 00000046 RAX: 0000000080010002 RBX: ffff88816e8a5f68 RCX: 0000000000000000 RDX: ffff888157add700 RSI: ffffffff89ae0300 RDI: ffff88816e8a5f68 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff81675625 R11: 0000000000000000 R12: 00000305d54eab67 R13: ffff8880b9c2a480 R14: ffff8880b9c2a400 R15: ffff8880b9c2a400 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f21753d4bd0 CR3: 000000015a6b1000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline] debug_deactivate kernel/time/hrtimer.c:481 [inline] __run_hrtimer kernel/time/hrtimer.c:1653 [inline] __hrtimer_run_queues+0x3f8/0xe50 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:kasan_check_range+0x16/0x180 mm/kasan/generic.c:188 Code: a8 01 48 0f 45 fa e8 89 78 ec ff 0f 0b 0f 1f 80 00 00 00 00 48 85 f6 0f 84 3c 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 ff ff ff ff ff 7f ff ff 48 39 c7 0f 86 RSP: 0018:ffffc900220c7790 EFLAGS: 00000286 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff81acc5fb RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffea000173c640 RBP: ffffea000173c640 R08: 0000000000000000 R09: ffffea000173c648 R10: 0000000000000001 R11: 0000000000000000 R12: ffffea000173c648 R13: ffff88817fcf6cf8 R14: dffffc0000000000 R15: 00007f21731a0000 instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] PageCompound include/linux/page-flags.h:242 [inline] page_mapcount include/linux/mm.h:836 [inline] zap_pte_range mm/memory.c:1358 [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+0xf1b/0x29f0 mm/memory.c:1538 unmap_single_vma+0x198/0x310 mm/memory.c:1583 unmap_vmas+0x16b/0x2f0 mm/memory.c:1615 exit_mmap+0x1d0/0x630 mm/mmap.c:3170 __mmput+0x122/0x4b0 kernel/fork.c:1113 mmput+0x56/0x60 kernel/fork.c:1134 exit_mm kernel/exit.c:507 [inline] do_exit+0xb27/0x2b40 kernel/exit.c:819 do_group_exit+0x125/0x310 kernel/exit.c:929 get_signal+0x47d/0x2220 kernel/signal.c:2830 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:868 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: 0033:0x7f21753feae9 Code: Unable to access opcode bytes at RIP 0x7f21753feabf. RSP: 002b:00007f2172974218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f2175511f68 RCX: 00007f21753feae9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f2175511f68 RBP: 00007f2175511f60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2175511f6c R13: 00007f2175a45b2f R14: 00007f2172974300 R15: 0000000000022000 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: ff 48 89 decl -0x77(%rax) 3: cf iret 4: 48 89 54 24 18 mov %rdx,0x18(%rsp) 9: 48 89 4c 24 10 mov %rcx,0x10(%rsp) e: e8 74 8f df fd callq 0xfddf8f87 13: 48 8b 54 24 18 mov 0x18(%rsp),%rdx 18: 48 8b 4c 24 10 mov 0x10(%rsp),%rcx 1d: e9 e2 f4 ff ff jmpq 0xfffff504 22: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 27: 41 57 push %r15 * 29: 41 56 push %r14 <-- trapping instruction 2b: 41 55 push %r13 2d: 41 54 push %r12 2f: 49 bc 00 00 00 00 00 movabs $0xdffffc0000000000,%r12 36: fc ff df 39: 55 push %rbp 3a: 53 push %rbx 3b: 48 rex.W 3c: 81 .byte 0x81 3d: ec in (%dx),%al 3e: b0 .byte 0xb0