rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 ticks this GP) idle=7fc4/1/0x4000000000000000 softirq=17445/17445 fqs=1
rcu: (detected by 0, t=12680 jiffies, g=17669, q=472 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 1013 Comm: kworker/u8:7 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: writeback wb_workfn (flush-8:0)
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:146 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:172 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:191 [inline]
RIP: 0010:kasan_check_range+0x24b/0x2c0 mm/kasan/generic.c:200
Code: 0f 85 82 00 00 00 49 c1 ef 30 bb 07 00 00 00 45 84 ff 75 7d 4d 01 f3 49 01 db 4d 89 dc 4d 85 db 74 84 4d 01 d1 4d 39 cc 75 11 <41> 83 e0 07 45 0f be 09 45 39 c8 0f 8c 6b ff ff ff 0f b6 d2 e8 3c
RSP: 0018:ffffc90000a18c08 EFLAGS: 00000046
RAX: 00000000ffffff01 RBX: ffffffffffffffff RCX: ffffffff81a3ebfb
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90000a18c80
RBP: ffffc90000a18ce8 R08: ffffc90000a18c83 R09: fffff52000143190
R10: dffffc0000000000 R11: fffff52000143190 R12: fffff52000143190
R13: ffff8880282662b0 R14: fffff52000143191 R15: 1ffff92000143190
FS: 0000000000000000(0000) GS:ffff888124dc8000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005556b123ba38 CR3: 000000007f2dc000 CR4: 00000000003526f0
Call Trace:
instrument_read_write include/linux/instrumented.h:55 [inline]
atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1301 [inline]
queued_spin_lock include/asm-generic/qspinlock.h:112 [inline]
do_raw_spin_lock+0x12b/0x2f0 kernel/locking/spinlock_debug.c:116
spin_lock include/linux/spinlock.h:347 [inline]
advance_sched+0xc2/0xc80 net/sched/sch_taprio.c:931
__run_hrtimer kernel/time/hrtimer.c:2074 [inline]
__hrtimer_run_queues+0x3bc/0xa10 kernel/time/hrtimer.c:2131
hrtimer_interrupt+0x4cd/0xaa0 kernel/time/hrtimer.c:2250
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
__sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:csd_lock_wait kernel/smp.c:363 [inline]
RIP: 0010:smp_call_function_many_cond+0x1132/0x1500 kernel/smp.c:1002
Code: 78 44 8b 2b 44 89 ee 83 e6 01 31 ff e8 27 4b 0c 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 12 46 0c 00 eb 35 f3 90 <43> 0f b6 04 2c 84 c0 75 0f f7 03 01 00 00 00 74 1d e8 f8 45 0c 00
RSP: 0018:ffffc900050a6460 EFLAGS: 00000293
RAX: ffffffff81bba538 RBX: ffff8880b8643708 RCX: ffff888027f83e80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900050a65b0 R08: ffff88807fa179c7 R09: 1ffff1100ff42f38
R10: dffffc0000000000 R11: ffffffff8179dc60 R12: 1ffff110170c86e1
R13: dffffc0000000000 R14: 1ffff11004ff0a83 R15: 0000000000000000
__flush_tlb_multi arch/x86/include/asm/paravirt.h:46 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
flush_tlb_mm_range+0x8ff/0x1090 arch/x86/mm/tlb.c:1435
flush_tlb_page arch/x86/include/asm/tlbflush.h:352 [inline]
ptep_clear_flush+0x120/0x170 mm/pgtable-generic.c:104
page_vma_mkclean_one+0x4b9/0x840 mm/rmap.c:1146
page_mkclean_one+0x20c/0x2e0 mm/rmap.c:1194
__rmap_walk_file+0x4cd/0x6a0 mm/rmap.c:3120
rmap_walk mm/rmap.c:3164 [inline]
folio_mkclean+0x2d5/0x3f0 mm/rmap.c:1226
folio_clear_dirty_for_io+0x190/0x820 mm/page-writeback.c:2903
mpage_submit_folio+0x83/0x2a0 fs/ext4/inode.c:2075
mpage_map_and_submit_buffers fs/ext4/inode.c:2331 [inline]
mpage_map_and_submit_extent fs/ext4/inode.c:2515 [inline]
ext4_do_writepages+0x203d/0x4770 fs/ext4/inode.c:2938
ext4_writepages+0x241/0x3b0 fs/ext4/inode.c:3032
do_writepages+0x338/0x560 mm/page-writeback.c:2560
__writeback_single_inode+0x136/0x1220 fs/fs-writeback.c:1803
writeback_sb_inodes+0x9de/0x1b00 fs/fs-writeback.c:2114
__writeback_inodes_wb+0x114/0x240 fs/fs-writeback.c:2190
wb_writeback+0x42f/0xad0 fs/fs-writeback.c:2301
wb_check_old_data_flush fs/fs-writeback.c:2405 [inline]
wb_do_writeback fs/fs-writeback.c:2484 [inline]
wb_workfn+0xc92/0x10f0 fs/fs-writeback.c:2512
process_one_work kernel/workqueue.c:3396 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: rcu_preempt kthread timer wakeup didn't happen for 9225 jiffies! g17669 f0x0 RCU_GP_WAIT_FQS(5) ->state=I
rcu: Possible timer handling issue on cpu=0 timer-softirq=5574
rcu: rcu_preempt kthread starved for 9226 jiffies! g17669 f0x0 RCU_GP_WAIT_FQS(5) ->state=I ->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:28104 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5533 [inline]
__schedule+0x17db/0x58f0 kernel/sched/core.c:7284
__schedule_loop kernel/sched/core.c:7361 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7376
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2122
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2330
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 5670 Comm: udevd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:csd_lock_wait kernel/smp.c:363 [inline]
RIP: 0010:smp_call_function_many_cond+0x1132/0x1500 kernel/smp.c:1002
Code: 78 44 8b 2b 44 89 ee 83 e6 01 31 ff e8 27 4b 0c 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 12 46 0c 00 eb 35 f3 90 <43> 0f b6 04 2c 84 c0 75 0f f7 03 01 00 00 00 74 1d e8 f8 45 0c 00
RSP: 0018:ffffc9000435f560 EFLAGS: 00000293
RAX: ffffffff81bba538 RBX: ffff8880b87414c8 RCX: ffff888079d48000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000435f6b0 R08: ffffffff907a627f R09: 1ffffffff20f4c4f
R10: dffffc0000000000 R11: fffffbfff20f4c50 R12: 1ffff110170e8299
R13: dffffc0000000000 R14: 1ffff1100f3a92b3 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888124cc8000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3f58c0be80 CR3: 000000000eb48000 CR4: 00000000003526f0
Call Trace:
__flush_tlb_multi arch/x86/include/asm/paravirt.h:46 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
flush_tlb_mm_range+0x8ff/0x1090 arch/x86/mm/tlb.c:1435
tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:509 [inline]
tlb_flush_mmu+0x1af/0xa30 mm/mmu_gather.c:423
tlb_finish_mmu+0xf4/0x220 mm/mmu_gather.c:549
free_ldt_pgtables+0x192/0x360 arch/x86/kernel/ldt.c:411
arch_exit_mmap arch/x86/include/asm/mmu_context.h:229 [inline]
exit_mmap+0x1bf/0x9f0 mm/mmap.c:1300
__mmput+0x118/0x420 kernel/fork.c:1193
exit_mm+0x18e/0x240 kernel/exit.c:592
do_exit+0x6cd/0x2360 kernel/exit.c:974
do_group_exit+0x22d/0x2f0 kernel/exit.c:1129
__do_sys_exit_group kernel/exit.c:1140 [inline]
__se_sys_exit_group kernel/exit.c:1138 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1138
x64_sys_call+0x18c6/0x18d0 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3f584f16c5
Code: Unable to access opcode bytes at 0x7f3f584f169b.
RSP: 002b:00007ffcc1e34c18 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00005556b12554d0 RCX: 00007f3f584f16c5
RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000
RBP: 00005556b1232910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffcc1e34c60 R14: 0000000000000000 R15: 0000000000000000