rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5545/2:b..l rcu: (detected by 0, t=10502 jiffies, g=13513, q=595 ncpus=2) task:syz.3.57 state:R running task stack:25936 pid:5545 tgid:5542 ppid:5226 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:__sanitizer_cov_trace_const_cmp4+0x8/0x20 kernel/kcov.c:313 Code: bf 03 00 00 00 e9 58 fe ff ff 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 0c 24 <89> f2 89 fe bf 05 00 00 00 e9 2a fe ff ff 66 2e 0f 1f 84 00 00 00 RSP: 0018:ffffc900037df300 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffea000168da74 RCX: ffffffff81bf290c RDX: ffff88802bb59e00 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffea000168da40 R08: 0000000000000001 R09: fffff940002d1b4e R10: ffffea000168da77 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000001 R14: ffffea000168da40 R15: dffffc0000000000 raw_atomic_fetch_add_unless include/linux/atomic/atomic-arch-fallback.h:2429 [inline] raw_atomic_add_unless include/linux/atomic/atomic-arch-fallback.h:2456 [inline] atomic_add_unless include/linux/atomic/atomic-instrumented.h:1518 [inline] page_ref_add_unless.constprop.0+0x31c/0x390 include/linux/page_ref.h:238 folio_ref_add_unless include/linux/page_ref.h:248 [inline] folio_try_get include/linux/page_ref.h:264 [inline] find_get_entry mm/filemap.c:2004 [inline] find_lock_entries+0x1bd/0xc10 mm/filemap.c:2091 shmem_undo_range+0x217/0x1160 mm/shmem.c:1005 shmem_truncate_range mm/shmem.c:1132 [inline] shmem_evict_inode+0x3a3/0xba0 mm/shmem.c:1260 evict+0x409/0x970 fs/inode.c:731 iput_final fs/inode.c:1883 [inline] iput.part.0+0x5cf/0x820 fs/inode.c:1909 iput+0x62/0x80 fs/inode.c:1899 dentry_unlink_inode+0x29c/0x480 fs/dcache.c:412 __dentry_kill+0x1d0/0x600 fs/dcache.c:615 dput.part.0+0x4b1/0x9b0 fs/dcache.c:857 dput+0x1f/0x30 fs/dcache.c:847 __fput+0x513/0xb60 fs/file_table.c:439 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+0x25fb/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] irqentry_exit_to_user_mode+0x13f/0x280 kernel/entry/common.c:231 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0033:0x7fd1a404daf0 RSP: 002b:00007fd1a4ff0060 EFLAGS: 00000202 RAX: 0000000020000000 RBX: 00007fd1a4336058 RCX: 00007fd1a41f0b76 RDX: 0000000000000000 RSI: 0000000000b36000 RDI: 0000000020000000 RBP: 00007fd1a41f0b76 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fd1a4336058 R15: 00007ffe96e84978 rcu: rcu_preempt kthread starved for 10542 jiffies! g13513 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:27584 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-syzkaller-02574-ga430d95c5efa #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 78 a2 eb 74 48 8b 00 a8 08 75 0c 66 90 0f 00 2d 68 56 a4 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: ffffffff8b181979 RDX: 0000000000000001 RSI: ffff8880212ad800 RDI: ffff8880212ad864 RBP: ffff8880212ad864 R08: 0000000000000001 R09: ffffed1017106fd9 R10: ffff8880b8837ecb R11: 0000000000000000 R12: ffff88801ffd1800 R13: ffffffff8e9faa20 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020009030 CR3: 0000000033d9a000 CR4: 00000000003526f0 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+0xaa/0x4f0 drivers/cpuidle/cpuidle.c:264 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:385 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+0x3e4/0x4d0 init/main.c:1105 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