rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (2 ticks this GP) idle=b724/1/0x4000000000000000 softirq=29822/29822 fqs=5
rcu: 	(detected by 1, t=10503 jiffies, g=21153, q=1190 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 69 Comm: kworker/u8:4 Not tainted 6.15.0-syzkaller-11980-g16b70698aa3a #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: writeback wb_workfn (flush-8:0)
RIP: 0010:__run_hrtimer kernel/time/hrtimer.c:1759 [inline]
RIP: 0010:__hrtimer_run_queues+0x4fd/0xc40 kernel/time/hrtimer.c:1825
Code: 4d 89 f3 2e e8 5c 53 53 1e 41 89 c6 eb 64 e8 6a d7 11 00 65 4c 8b 3c 25 08 20 f5 91 49 81 c7 e0 0a 00 00 4d 89 fd 49 c1 ed 03 <48> bb 00 00 00 00 00 fc ff df 41 0f b6 44 1d 00 84 c0 0f 85 64 03
RSP: 0018:ffffc90000007d40 EFLAGS: 00000806
RAX: ffffffff81acc426 RBX: ffff8880b8827c88 RCX: ffff88801b748000
RDX: 0000000000010000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000007e90 R08: ffffffff8f1376f7 R09: 1ffffffff1e26ede
R10: dffffc0000000000 R11: fffffbfff1e26edf R12: ffff888076090340
R13: 1ffff110036e915c R14: ffffffff891e66b0 R15: ffff88801b748ae0
FS:  0000000000000000(0000) GS:ffff8881268ce000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055df917c8a08 CR3: 0000000030e60000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 hrtimer_interrupt+0x457/0xa90 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
 __sysvec_apic_timer_interrupt+0x104/0x3f0 arch/x86/kernel/apic/apic.c:1056
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:130 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:161 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x6d/0x2b0 mm/kasan/generic.c:189
Code: 00 49 89 ff 49 c1 ef 03 49 ba 00 00 00 00 00 fc ff df 4f 8d 1c 17 49 ff c8 4d 89 c1 49 c1 e9 03 48 bb 01 00 00 00 00 fc ff df <4d> 8d 34 19 4d 89 f4 4d 29 dc 49 83 fc 10 7f 29 4d 85 e4 0f 84 41
RSP: 0018:ffffc9000214ec08 EFLAGS: 00000a03
RAX: ffffffff82701401 RBX: dffffc0000000001 RCX: ffffffff8270148e
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffea00018a7c00
RBP: ffffc9000214f050 R08: ffffea00018a7c07 R09: 1ffffd4000314f80
R10: dffffc0000000000 R11: fffff94000314f80 R12: ffffc9000214f0b8
R13: ffffea00018a7c00 R14: dffffc0000000000 R15: 1ffffd4000314f80
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 folio_test_head include/linux/page-flags.h:867 [inline]
 folio_test_large include/linux/page-flags.h:888 [inline]
 folio_nr_pages include/linux/mm.h:1976 [inline]
 mpage_folio_done fs/ext4/inode.c:2027 [inline]
 mpage_map_and_submit_buffers fs/ext4/inode.c:2306 [inline]
 mpage_map_and_submit_extent fs/ext4/inode.c:2439 [inline]
 ext4_do_writepages+0x1e5e/0x3f10 fs/ext4/inode.c:2863
 ext4_writepages+0x201/0x350 fs/ext4/inode.c:2953
 do_writepages+0x327/0x550 mm/page-writeback.c:2636
 __writeback_single_inode+0x145/0xfc0 fs/fs-writeback.c:1680
 writeback_sb_inodes+0x6b1/0xff0 fs/fs-writeback.c:1976
 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2047
 wb_writeback+0x44b/0xad0 fs/fs-writeback.c:2158
 wb_check_old_data_flush fs/fs-writeback.c:2262 [inline]
 wb_do_writeback fs/fs-writeback.c:2315 [inline]
 wb_workfn+0xadf/0xee0 fs/fs-writeback.c:2343
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xada/0x1780 kernel/workqueue.c:3321
 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3402
 kthread+0x70a/0x890 kernel/kthread.c:464
 ret_from_fork+0x3f4/0x750 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 8328 jiffies! g21153 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=6241
rcu: rcu_preempt kthread starved for 8329 jiffies! g21153 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27200 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x16f1/0x4c90 kernel/sched/core.c:6785
 __schedule_loop kernel/sched/core.c:6863 [inline]
 schedule+0x161/0x360 kernel/sched/core.c:6878
 schedule_timeout+0x127/0x260 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x2fd/0x1520 kernel/rcu/tree.c:2054
 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:2256
 kthread+0x70a/0x890 kernel/kthread.c:464
 ret_from_fork+0x3f4/0x750 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>