rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P10881/1:b..l rcu: (detected by 0, t=10502 jiffies, g=56045, q=436 ncpus=2) task:syz.0.1069 state:R running task stack:24816 pid:10881 tgid:10879 ppid:7170 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xe37/0x5490 kernel/sched/core.c:6529 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:6851 irqentry_exit+0x36/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:kthread_blkcg+0x1d/0x160 kernel/kthread.c:1545 Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 55 53 e8 95 f7 32 00 48 b8 00 00 00 00 00 fc ff df 65 48 8b 1d 63 5a ac 7e <48> 8d 7b 2c 48 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 RSP: 0018:ffffc90003bf7310 EFLAGS: 00000293 RAX: dffffc0000000000 RBX: ffff88802b7d5a00 RCX: ffffffff846bce6d RDX: ffff88802b7d5a00 RSI: ffffffff8157808b RDI: ffff88802efa9688 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88802efa96c8 R13: 0000000000000004 R14: 0000000000000801 R15: 0000000000000001 blkcg_css block/blk-cgroup.c:107 [inline] bio_associate_blkg block/blk-cgroup.c:2110 [inline] bio_associate_blkg+0x1d4/0x2a0 block/blk-cgroup.c:2098 bio_init+0x2ae/0x5a0 block/bio.c:265 bio_alloc_bioset+0x2c5/0x8b0 block/bio.c:580 bio_alloc include/linux/bio.h:374 [inline] submit_bh_wbc+0x280/0x730 fs/buffer.c:2804 __block_write_full_folio+0x729/0xe00 fs/buffer.c:1913 block_write_full_folio+0x342/0x400 fs/buffer.c:2753 write_cache_pages+0xb0/0x130 mm/page-writeback.c:2640 blkdev_writepages+0xa4/0xf0 block/fops.c:436 do_writepages+0x1a3/0x7f0 mm/page-writeback.c:2683 filemap_fdatawrite_wbc mm/filemap.c:397 [inline] filemap_fdatawrite_wbc+0x148/0x1c0 mm/filemap.c:387 __filemap_fdatawrite_range+0xba/0x100 mm/filemap.c:430 filemap_write_and_wait_range mm/filemap.c:685 [inline] filemap_write_and_wait_range+0xa3/0x130 mm/filemap.c:676 filemap_write_and_wait include/linux/pagemap.h:66 [inline] sync_blockdev block/bdev.c:218 [inline] sync_blockdev block/bdev.c:214 [inline] bdev_release+0x4eb/0x6f0 block/bdev.c:1078 blkdev_release+0x15/0x20 block/fops.c:638 __fput+0x408/0xbb0 fs/file_table.c:422 task_work_run+0x14e/0x250 kernel/task_work.c:228 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xaa3/0x2bb0 kernel/exit.c:882 do_group_exit+0xd3/0x2a0 kernel/exit.c:1031 get_signal+0x25fd/0x2770 kernel/signal.c:2917 arch_do_signal_or_restart+0x90/0x7e0 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+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3875579e79 RSP: 002b:00007f387631f0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f3875716060 RCX: 00007f3875579e79 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f3875716060 RBP: 00007f3875716058 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3875716064 R13: 0000000000000000 R14: 00007ffdbaf0b1f0 R15: 00007ffdbaf0b2d8 rcu: rcu_preempt kthread starved for 10553 jiffies! g56045 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:27312 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xe37/0x5490 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6621 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2034 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2236 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 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: CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.11.0-rc3-syzkaller-00221-g670c12ce09a8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:92 [inline] RIP: 0010:acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:112 Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 65 48 8b 05 88 c7 f2 74 48 8b 00 a8 08 75 0c 66 90 0f 00 2d 38 e8 aa 00 fb f4 c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffffff8da07d70 EFLAGS: 00000246 RAX: 0000000000004000 RBX: 0000000000000001 RCX: ffffffff8b10f699 RDX: 0000000000000001 RSI: ffff888019e9f800 RDI: ffff888019e9f864 RBP: ffff888019e9f864 R08: 0000000000000001 R09: ffffed1017246fd9 R10: ffff8880b9237ecb R11: 0000000000000000 R12: ffff888019b0d800 R13: ffffffff8e9520c0 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c361d63 CR3: 0000000024564000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:702 cpuidle_enter_state+0x85/0x500 drivers/cpuidle/cpuidle.c:267 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:388 cpuidle_idle_call kernel/sched/idle.c:230 [inline] do_idle+0x313/0x3f0 kernel/sched/idle.c:326 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:424 rest_init+0x16b/0x2b0 init/main.c:747 start_kernel+0x3df/0x4c0 init/main.c:1103 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x148