rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P11526/1:b..l P5826/1:b..l P12310/1:b..l rcu: (detected by 0, t=10502 jiffies, g=44905, q=468 ncpus=2) task:syz-executor state:R running task stack:23744 pid:12310 tgid:12310 ppid:5815 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7078 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:seqcount_lockdep_reader_access+0x1d6/0x220 include/linux/seqlock.h:75 Code: 62 e8 de c5 77 ff 4d 85 f6 48 bb 00 00 00 00 00 fc ff df 75 07 e8 ca c5 77 ff eb 06 e8 c3 c5 77 ff fb 48 c7 04 24 0e 36 e0 45 <4a> c7 04 23 00 00 00 00 66 42 c7 44 23 09 00 00 42 c6 44 23 0b 00 RSP: 0018:ffffc90003217800 EFLAGS: 00000293 RAX: ffffffff8227987d RBX: dffffc0000000000 RCX: ffff888028c4bc00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900032178a8 R08: ffffffff82279858 R09: 1ffffffff2854318 R10: dffffc0000000000 R11: fffffbfff2854319 R12: 1ffff92000642f00 R13: ffffc90003217820 R14: 0000000000000200 R15: 0000000000000046 read_seqbegin include/linux/seqlock.h:813 [inline] read_seqbegin_or_lock include/linux/seqlock.h:1107 [inline] __dentry_path+0x16c/0x6b0 fs/d_path.c:341 dentry_path_raw+0x141/0x210 fs/d_path.c:367 tomoyo_get_dentry_path security/tomoyo/realpath.c:131 [inline] tomoyo_get_local_path+0xd2/0x7b0 security/tomoyo/realpath.c:157 tomoyo_realpath_from_path+0x49c/0x5e0 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_number_perm+0x236/0x860 security/tomoyo/file.c:723 security_file_ioctl+0xc6/0x2a0 security/security.c:2908 __do_sys_ioctl fs/ioctl.c:900 [inline] __se_sys_ioctl+0x46/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7210d8591b RSP: 002b:00007ffeb5275150 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000080000 RCX: 00007f7210d8591b RDX: 0000000000080000 RSI: ffffffff80086301 RDI: 00000000000000d9 RBP: 00007f7210f76118 R08: 00000000000000d8 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000 task:syz-executor state:R running task stack:19800 pid:5826 tgid:5826 ppid:5825 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6935 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6959 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] copy_pte_range mm/memory.c:1200 [inline] copy_pmd_range+0x6dc8/0x77a0 mm/memory.c:1261 copy_pud_range mm/memory.c:1298 [inline] copy_p4d_range mm/memory.c:1322 [inline] copy_page_range+0x99f/0xe90 mm/memory.c:1420 dup_mmap kernel/fork.c:751 [inline] dup_mm kernel/fork.c:1695 [inline] copy_mm+0x11c7/0x1f90 kernel/fork.c:1744 copy_process+0x1845/0x3d50 kernel/fork.c:2395 kernel_clone+0x226/0x8e0 kernel/fork.c:2807 __do_sys_clone kernel/fork.c:2950 [inline] __se_sys_clone kernel/fork.c:2934 [inline] __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2934 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fae0f17c593 RSP: 002b:00007ffe8a7eefc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fae0f17c593 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 0000555590b437d0 R11: 0000000000000246 R12: 0000000000000000 R13: 0000555590b56590 R14: 00007ffe8a7ef150 R15: 0000000000000144 task:syz-executor state:R running task stack:19216 pid:11526 tgid:11526 ppid:11513 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6935 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6959 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] copy_pte_range mm/memory.c:1200 [inline] copy_pmd_range+0x6dc8/0x77a0 mm/memory.c:1261 copy_pud_range mm/memory.c:1298 [inline] copy_p4d_range mm/memory.c:1322 [inline] copy_page_range+0x99f/0xe90 mm/memory.c:1420 dup_mmap kernel/fork.c:751 [inline] dup_mm kernel/fork.c:1695 [inline] copy_mm+0x11c7/0x1f90 kernel/fork.c:1744 copy_process+0x1845/0x3d50 kernel/fork.c:2395 kernel_clone+0x226/0x8e0 kernel/fork.c:2807 __do_sys_clone kernel/fork.c:2950 [inline] __se_sys_clone kernel/fork.c:2934 [inline] __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2934 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9d73f7c593 RSP: 002b:00007ffedc1f6148 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f9d73f7c593 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 0000555567c907d0 R11: 0000000000000246 R12: 0000000000000000 R13: 0000555567ca3590 R14: 00007ffedc1f62d0 R15: 0000000000000018 rcu: rcu_preempt kthread starved for 240 jiffies! g44905 f0x0 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:26072 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:111