rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P25011/1:b..l P25019/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=143393, q=189 ncpus=2)
task:syz.6.4469 state:R running task stack:21984 pid:25019 tgid:25019 ppid:20564 task_flags:0x40064c flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6894
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7221
irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x222/0x340 kernel/locking/lockdep.c:5872
Code: ff ff ff e8 60 9c bf 09 f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 7a 9a 03 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d 97 ad 07
RSP: 0018:ffffc90003d5ecf8 EFLAGS: 00000282
RAX: 28cffc3b0db8d800 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 000000005a44979c RSI: ffffffff8db845c0 RDI: ffffffff8be08c60
RBP: ffffffff8173fd75 R08: ffffffff8173fd75 R09: ffffffff8e13efa0
R10: ffffc90003d5ee58 R11: ffffffff81acb2b0 R12: 0000000000000002
R13: ffffffff8e13efa0 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
rcu_read_lock include/linux/rcupdate.h:850 [inline]
class_rcu_constructor include/linux/rcupdate.h:1193 [inline]
unwind_next_frame+0xc2/0x23d0 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf5/0x1f0 mm/page_owner.c:165
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1436 [inline]
free_unref_folios+0xcc0/0x13e0 mm/page_alloc.c:3033
folios_put_refs+0x584/0x670 mm/swap.c:1002
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x49e/0x1490 mm/shmem.c:1137
shmem_truncate_range mm/shmem.c:1249 [inline]
shmem_evict_inode+0x26e/0xa70 mm/shmem.c:1379
evict+0x5f4/0xae0 fs/inode.c:837
__dentry_kill+0x209/0x660 fs/dcache.c:670
finish_dput+0xc9/0x480 fs/dcache.c:879
__fput+0x68e/0xa70 fs/file_table.c:476
task_work_run+0x1d4/0x260 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x694/0x22f0 kernel/exit.c:971
do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
get_signal+0x1285/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop kernel/entry/common.c:75 [inline]
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline]
irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline]
irqentry_exit+0x178/0x670 kernel/entry/common.c:196
exc_general_protection+0x171/0x1f0 arch/x86/kernel/traps.c:913
asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:612
RIP: 0033:0x7fdb5078f751
RSP: 002b:0000200000000550 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fdb509e6180 RCX: 00007fdb5078f749
RDX: 0000200000000580 RSI: 0000200000000550 RDI: 0000000000000200
RBP: 00007fdb50813f91 R08: 0000200000000600 R09: 0000200000000600
R10: 00002000000005c0 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fdb509e6218 R14: 00007fdb509e6180 R15: 00007ffe52855ad8
task:syz.9.4467 state:R running task stack:22208 pid:25011 tgid:25011 ppid:20832 task_flags:0x400640 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6894
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7221
irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__sanitizer_cov_trace_pc+0x5d/0x70 kernel/kcov.c:235
Code: 20 16 00 00 83 fa 02 75 21 48 8b 91 28 16 00 00 48 8b 32 48 8d 7e 01 8b 89 24 16 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 08 3e b5 9f 09 cc 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90
RSP: 0018:ffffc9000b496728 EFLAGS: 00000293
RAX: ffffffff8b5b2bdd RBX: dffffc0000000000 RCX: ffff88801b7a0000
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000002
RBP: ffff888011bc4000 R08: ffffffff81f9b99d R09: ffffffff8e13efa0
R10: ffffc9000b496800 R11: fffff52001692d03 R12: 0000000000000002
R13: dffffc0000000000 R14: ffff888056e118c2 R15: 0000000000000004
xas_descend lib/xarray.c:211 [inline]
xas_load+0x44d/0x5b0 lib/xarray.c:246
filemap_get_entry+0x168/0x2f0 mm/filemap.c:1895
shmem_get_folio_gfp+0x237/0x1660 mm/shmem.c:2463
shmem_get_folio mm/shmem.c:2645 [inline]
shmem_write_begin+0x16c/0x330 mm/shmem.c:3298
generic_perform_write+0x2c5/0x900 mm/filemap.c:4314
shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3473
__kernel_write_iter+0x428/0x910 fs/read_write.c:619
dump_emit_page fs/coredump.c:1298 [inline]
dump_user_range+0x8a0/0xc90 fs/coredump.c:1372
elf_core_dump+0x3369/0x3960 fs/binfmt_elf.c:2111
coredump_write+0x1121/0x18b0 fs/coredump.c:1049
do_coredump fs/coredump.c:1126 [inline]
vfs_coredump+0x3321/0x3e60 fs/coredump.c:1200
get_signal+0x1108/0x1340 kernel/signal.c:3019
arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop kernel/entry/common.c:75 [inline]
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline]
irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline]
irqentry_exit+0x178/0x670 kernel/entry/common.c:196
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f3c0b18f751
RSP: 002b:fffffffffffffe70 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f3c0b3e6180 RCX: 00007f3c0b18f749
RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000
RBP: 00007f3c0b213f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f3c0b3e6218 R14: 00007f3c0b3e6180 R15: 00007ffcbed2fd78
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g143393 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=110504
rcu: rcu_preempt kthread starved for 10502 jiffies! g143393 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:27640 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6894
__schedule_loop kernel/sched/core.c:6976 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6991
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x11b0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9b/0x2d0 kernel/rcu/tree.c:2297
kthread+0x389/0x480 kernel/kthread.c:467
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:trace_lock_release include/trace/events/lock.h:69 [inline]
RIP: 0010:lock_release+0x44/0x3b0 kernel/locking/lockdep.c:5879
Code: 8b 05 90 6b 03 11 48 89 44 24 28 0f 1f 44 00 00 65 8b 05 93 6b 03 11 83 f8 08 0f 83 57 02 00 00 89 c0 48 0f a3 05 bc 38 04 0e <73> 0d e8 c5 9e 08 00 84 c0 0f 84 95 02 00 00 83 3d b6 68 04 0e 00
RSP: 0018:ffffc90000007bf8 EFLAGS: 00000093
RAX: 0000000000000000 RBX: ffff888035c202a8 RCX: 1ffff11006b8405d
RDX: 0000000000010000 RSI: ffffffff89744d2f RDI: ffff888035c202c0
RBP: ffff88804b210d50 R08: ffff88804b210c87 R09: 1ffff11009642190
R10: dffffc0000000000 R11: ffffed1009642191 R12: ffff888035c20300
R13: ffffffff89744d2f R14: ffff888035c202c0 R15: ffff88804b213400
FS: 0000000000000000(0000) GS:ffff888125c07000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000044c0 CR3: 000000008b8a8000 CR4: 00000000003526f0
Call Trace:
__raw_spin_unlock include/linux/spinlock_api_smp.h:167 [inline]
_raw_spin_unlock+0x16/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:392 [inline]
advance_sched+0x99f/0xc90 net/sched/sch_taprio.c:987
__run_hrtimer kernel/time/hrtimer.c:1777 [inline]
__hrtimer_run_queues+0x51c/0xc30 kernel/time/hrtimer.c:1841
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
__sysvec_apic_timer_interrupt+0x102/0x3e0 arch/x86/kernel/apic/apic.c:1062
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
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 43 be 2a 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8de07dc0 EFLAGS: 000002c2
RAX: 0000000001f874d5 RBX: ffffffff8197161e RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d9a0b7f RDI: ffffffff8be08c60
RBP: ffffffff8de07eb0 R08: ffff8880b863375b R09: 1ffff110170c66eb
R10: dffffc0000000000 R11: ffffed10170c66ec R12: ffffffff8fa25d70
R13: 1ffffffff1bd29b8 R14: 0000000000000000 R15: 0000000000000000
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x1be/0x4d0 kernel/sched/idle.c:332
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
rest_init+0x2de/0x300 init/main.c:757
start_kernel+0x386/0x3d0 init/main.c:1207
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x147