rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6409/1:b..l rcu: (detected by 1, t=10502 jiffies, g=19673, q=633 ncpus=2) task:syz.0.195 state:R running task stack:24640 pid:6409 tgid:6402 ppid:6085 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6851 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:check_kcov_mode kernel/kcov.c:193 [inline] RIP: 0010:write_comp_data kernel/kcov.c:245 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x35/0x90 kernel/kcov.c:320 Code: 0c 25 c0 d6 03 00 65 8b 05 20 47 70 7e 25 00 01 ff 00 74 10 3d 00 01 00 00 75 57 83 b9 1c 16 00 00 00 74 4e 8b 81 f8 15 00 00 <83> f8 03 75 43 48 8b 91 00 16 00 00 44 8b 89 fc 15 00 00 49 c1 e1 RSP: 0018:ffffc90004326d38 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffffff8156d0f7 RCX: ffff888029828000 RDX: 0000000000000000 RSI: ffffffff8156d0f7 RDI: 0000000000000000 RBP: ffffc90004326dd0 R08: ffffffff81378462 R09: ffffffff814140bf R10: 0000000000000003 R11: ffff888029828000 R12: ffff888029828000 R13: ffffffff817f30a0 R14: ffffc90004326e20 R15: ffffc90004326d40 arch_stack_walk+0x132/0x1b0 arch/x86/kernel/stacktrace.c:27 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 save_stack+0xfb/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x76/0x430 mm/page_owner.c:297 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1094 [inline] free_unref_folios+0x100f/0x1ac0 mm/page_alloc.c:2660 folios_put_refs+0x76e/0x860 mm/swap.c:1039 folio_batch_release include/linux/pagevec.h:101 [inline] shmem_undo_range+0x6de/0x1df0 mm/shmem.c:1023 shmem_truncate_range mm/shmem.c:1132 [inline] shmem_evict_inode+0x29b/0xa80 mm/shmem.c:1260 evict+0x532/0x950 fs/inode.c:704 __dentry_kill+0x20d/0x630 fs/dcache.c:610 dput+0x19f/0x2b0 fs/dcache.c:852 __fput+0x5f8/0x8a0 fs/file_table.c:430 task_work_run+0x24f/0x310 kernel/task_work.c:228 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xa2f/0x27f0 kernel/exit.c:882 do_group_exit+0x207/0x2c0 kernel/exit.c:1031 get_signal+0x1695/0x1730 kernel/signal.c:2917 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff5c3b79e79 RSP: 002b:00007ff5c4a11038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: 0000000000010106 RBX: 00007ff5c3d16058 RCX: 00007ff5c3b79e79 RDX: 0000000000010106 RSI: 00000000200000c0 RDI: 0000000000000006 RBP: 00007ff5c3be7916 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ff5c3d16058 R15: 00007ffc980abb18 rcu: rcu_preempt kthread starved for 10549 jiffies! g19673 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:24912 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2034 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2236 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/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 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline] NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:111