rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P17732/1:b..l rcu: (detected by 1, t=10502 jiffies, g=105221, q=327 ncpus=2) task:syz.3.3129 state:R running task stack:24048 pid:17732 tgid:17731 ppid:14919 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:lock_is_held_type+0x13b/0x190 Code: 75 44 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 4c 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 42 89 d8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f RSP: 0018:ffffc9000448ef30 EFLAGS: 00000206 RAX: 351199e6bc00c600 RBX: 0000000000000000 RCX: 0000000080000000 RDX: ffff888023185a00 RSI: ffffffff8beae6e0 RDI: ffffffff8c3f9280 RBP: 0000000000000002 R08: ffffffff8491bc6d R09: 1ffffffff269d300 R10: dffffc0000000000 R11: fffffbfff269d301 R12: 0000000000000246 R13: ffff888023185a00 R14: 00000000ffffffff R15: ffffffff8e765458 lock_is_held include/linux/lockdep.h:249 [inline] task_css include/linux/cgroup.h:433 [inline] blkcg_css+0xc9/0x1d0 block/blk-cgroup.c:110 blk_cgroup_congested+0xbb/0x200 block/blk-cgroup.c:2189 __folio_throttle_swaprate+0x84/0x1d0 mm/swapfile.c:3742 folio_throttle_swaprate include/linux/swap.h:641 [inline] shmem_add_to_page_cache+0x89c/0x1830 mm/shmem.c:796 shmem_alloc_and_add_folio+0x90b/0x14e0 mm/shmem.c:1814 shmem_get_folio_gfp+0x8dc/0x2370 mm/shmem.c:2192 shmem_fault+0x252/0x6f0 mm/shmem.c:2392 __do_fault+0x135/0x460 mm/memory.c:4655 do_read_fault mm/memory.c:5061 [inline] do_fault mm/memory.c:5191 [inline] do_pte_missing mm/memory.c:3947 [inline] handle_pte_fault+0x3b18/0x6eb0 mm/memory.c:5522 __handle_mm_fault mm/memory.c:5665 [inline] handle_mm_fault+0xf70/0x1880 mm/memory.c:5833 faultin_page mm/gup.c:1194 [inline] __get_user_pages+0x6ec/0x16a0 mm/gup.c:1493 populate_vma_page_range+0x264/0x330 mm/gup.c:1932 __mm_populate+0x27a/0x460 mm/gup.c:2035 mm_populate include/linux/mm.h:3415 [inline] vm_mmap_pgoff+0x2c3/0x3d0 mm/util.c:593 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: 0033:0x7fc062177299 RSP: 002b:00007fc062f89048 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007fc062305f80 RCX: 00007fc062177299 RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000000020000000 RBP: 00007fc0621e48e6 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fc062305f80 R15: 00007fffdcf15008 rcu: rcu_preempt kthread starved for 10391 jiffies! g105221 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:25656 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