rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P8909/2:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=41245, q=718 ncpus=2)
task:syz-executor    state:R  running task     stack:20968 pid:8909  tgid:8909  ppid:8895   task_flags:0x400140 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5360 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6964
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7291
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:197
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:raw_atomic_fetch_add_unless include/linux/atomic/atomic-arch-fallback.h:2429 [inline]
RIP: 0010:raw_atomic_add_unless include/linux/atomic/atomic-arch-fallback.h:2456 [inline]
RIP: 0010:atomic_add_unless include/linux/atomic/atomic-instrumented.h:1518 [inline]
RIP: 0010:page_ref_add_unless include/linux/page_ref.h:238 [inline]
RIP: 0010:folio_ref_add_unless include/linux/page_ref.h:248 [inline]
RIP: 0010:folio_try_get+0xf2/0x340 include/linux/page_ref.h:264
Code: c8 ff 49 83 c6 34 4c 89 f7 be 04 00 00 00 e8 b5 f2 2c 00 4c 89 f0 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 03 01 00 00 45 8b 3e <31> ff 44 89 fe e8 34 ee c8 ff 45 85 ff 0f 84 e1 00 00 00 41 8d 4f
RSP: 0018:ffffc900047c7510 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffffff81f7daec RCX: ffffffff81f7dbab
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffea000150b074
RBP: 0000000000000001 R08: ffffea000150b077 R09: 1ffffd40002a160e
R10: dffffc0000000000 R11: fffff940002a160f R12: dffffc0000000000
R13: fffffffffffffffe R14: ffffea000150b074 R15: 0000000000000001
 find_get_entry mm/filemap.c:2064 [inline]
 find_lock_entries+0x24f/0xa60 mm/filemap.c:2154
 shmem_undo_range+0x254/0x14b0 mm/shmem.c:1139
 shmem_truncate_range mm/shmem.c:1269 [inline]
 shmem_evict_inode+0x272/0xa70 mm/shmem.c:1397
 evict+0x501/0x9c0 fs/inode.c:810
 __dentry_kill+0x209/0x660 fs/dcache.c:669
 dput+0x19f/0x2b0 fs/dcache.c:911
 __fput+0x68e/0xa70 fs/file_table.c:476
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xec/0x130 kernel/entry/common.c:43
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f18f0d8d84a
RSP: 002b:00007ffe15ce9450 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007f18f0d8d84a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007ffe15ce94ac R08: 0000000000000000 R09: 00007ffe15ce91b7
R10: 0000000000000000 R11: 0000000000000293 R12: 000000000000000c
R13: 00000000000927c0 R14: 000000000005e01d R15: 00007ffe15ce9500
 </TASK>
rcu: rcu_preempt kthread starved for 10399 jiffies! g41245 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:27256 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5360 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6964
 __schedule_loop kernel/sched/core.c:7046 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7061
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
 kthread+0x70e/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x47c/0x820 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 33 61 29 00 f3 0f 1e fa fb f4 <e9> 08 e7 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197de0 EFLAGS: 000002c6
RAX: 31d55973286f4600 RBX: ffffffff81978e38 RCX: 31d55973286f4600
RDX: 0000000000000001 RSI: ffffffff8dbbd436 RDI: ffffffff8c037200
RBP: ffffc90000197f10 R08: ffff8880b8732f9b R09: 1ffff110170e65f3
R10: dffffc0000000000 R11: ffffed10170e65f4 R12: ffffffff8fc3ee30
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff11003a5cb58
FS:  0000000000000000(0000) GS:ffff888125af9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32d21ff8 CR3: 00000000778d2000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:757
 default_idle_call+0x74/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:190 [inline]
 do_idle+0x1e8/0x510 kernel/sched/idle.c:330
 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315
 common_startup_64+0x13e/0x147
 </TASK>