rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8204/1:b..l (detected by 1, t=10502 jiffies, g=47349, q=364 ncpus=2) task:syz.3.1053 state:R running task stack:25096 pid:8204 ppid:7945 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6558 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6870 irqentry_exit+0x53/0x80 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 RIP: 0010:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5666 Code: 2b 00 74 08 4c 89 f7 e8 0f a7 77 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc90004c675a0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff9200098cec0 RCX: 1ffff9200098ce60 RDX: dffffc0000000000 RSI: ffffffff8b0c13e0 RDI: ffffffff8b5d5e20 RBP: ffffc90004c676e8 R08: dffffc0000000000 R09: fffffbfff20e7445 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200098cebc R13: dffffc0000000000 R14: ffffc90004c67600 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] mapping_get_entry mm/filemap.c:1850 [inline] __filemap_get_folio+0x171/0xe80 mm/filemap.c:1915 shmem_get_folio_gfp+0x356/0x3470 mm/shmem.c:1881 shmem_get_folio mm/shmem.c:2072 [inline] shmem_write_begin+0x16e/0x4e0 mm/shmem.c:2559 generic_perform_write+0x2fc/0x5e0 mm/filemap.c:3817 __generic_file_write_iter+0x176/0x400 mm/filemap.c:3945 generic_file_write_iter+0xab/0x310 mm/filemap.c:3977 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x857/0xbc0 fs/read_write.c:584 ksys_write+0x19c/0x2c0 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fd7849784df RSP: 002b:00007fd78573fdf0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00000000013bd7ef RCX: 00007fd7849784df RDX: 00000000013bd7ef RSI: 00007fd77a7f7000 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 00000000000054f5 R10: 00000000000003ca R11: 0000000000000293 R12: 0000000000000003 R13: 00007fd78573fef0 R14: 00007fd78573feb0 R15: 00007fd77a7f7000 rcu: rcu_preempt kthread starved for 9570 jiffies! g47349 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:26144 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905 kthread+0x28d/0x320 kernel/kthread.c:376 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 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline] NMI backtrace for cpu 0 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:567