rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4188/1:b..l
	(detected by 1, t=10502 jiffies, g=10401, q=226)
task:syz-executor    state:R  running task     stack:21104 pid: 4188 ppid:  4184 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6799
 irqentry_exit+0x63/0x70 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_is_held_type+0x13a/0x190 kernel/locking/lockdep.c:5671
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c5 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc90002edf740 EFLAGS: 00000206
RAX: 3c26cff8fa09ad00 RBX: ffff888079e35940 RCX: 3c26cff8fa09ad00
RDX: 0000000000000000 RSI: ffffffff8a2b3e80 RDI: ffffffff8a7a2a40
RBP: 0000000000000001 R08: ffff888079e35940 R09: 0000000000000002
R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000001
R13: 0000000000000246 R14: ffffffff8c31ef20 R15: ffff888079e36458
 xa_parent+0x7c/0xf0 include/linux/xarray.h:1214
 xas_find+0x7ca/0xa50 lib/xarray.c:1262
 find_get_entry mm/filemap.c:1978 [inline]
 find_lock_entries+0x19e/0xd70 mm/filemap.c:2092
 shmem_undo_range+0x292/0x19a0 mm/shmem.c:943
 shmem_truncate_range mm/shmem.c:1063 [inline]
 shmem_evict_inode+0x1e2/0x9a0 mm/shmem.c:1145
 evict+0x4b6/0x8b0 fs/inode.c:647
 do_unlinkat+0x3e7/0x710 fs/namei.c:4363
 __do_sys_unlink fs/namei.c:4404 [inline]
 __se_sys_unlink fs/namei.c:4402 [inline]
 __x64_sys_unlink+0x45/0x50 fs/namei.c:4402
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f7e7eb8bf87
RSP: 002b:00007fff2f223538 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7e7eb8bf87
RDX: 00007fff2f223560 RSI: 00007fff2f2235f0 RDI: 00007fff2f2235f0
RBP: 00007fff2f2235f0 R08: 00007fff2f2245f0 R09: 00000000ffffffff
R10: 0000000000000100 R11: 0000000000000206 R12: 00007fff2f224680
R13: 00007f7e7ec2230a R14: 000000000001e1d5 R15: 00007fff2f2246c0
 </TASK>
rcu: rcu_preempt kthread starved for 9509 jiffies! g10401 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:27920 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2117
 rcu_gp_fqs_loop+0x2be/0x11f0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x9a/0x370 kernel/rcu/tree.c:2145
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 0 Comm: swapper/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <IRQ>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x1110/0x1270 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3936 [inline]
 rcu_sched_clock_irq+0x845/0x1120 kernel/rcu/tree.c:2619
 update_process_times+0x193/0x200 kernel/time/timer.c:2021
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x4b0/0xb60 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x397/0x8b0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:730
Code: b7 48 89 df e8 56 a7 f5 f7 eb ad e8 3f ac f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 00 cc 66 90 0f 00 2d 57 64 5d 00 fb f4 <c3> 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48
RSP: 0018:ffffc90000d67d48 EFLAGS: 000002c2
RAX: 7effe8d702ec5d00 RBX: ffff888016e98000 RCX: 7effe8d702ec5d00
RDX: 0000000000000001 RSI: ffffffff8a2b2be0 RDI: ffffffff8a7a2a40
RBP: ffffc90000d67e80 R08: ffff8880b913b30b R09: 1ffff11017227661
R10: dffffc0000000000 R11: ffffed1017227662 R12: 1ffff920001acfb4
R13: dffffc0000000000 R14: 1ffff11002dd3000 R15: 0000000000000000
 default_idle_call+0x81/0xc0 kernel/sched/idle.c:112
 cpuidle_idle_call kernel/sched/idle.c:202 [inline]
 do_idle+0x251/0x650 kernel/sched/idle.c:326
 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:424
 start_secondary+0x32f/0x430 arch/x86/kernel/smpboot.c:281
 secondary_startup_64_no_verify+0xb1/0xbb
 </TASK>