rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P13930/1:b..l P13834/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=75213, q=103 ncpus=2)
task:syz.5.2073 state:R running task stack:23176 pid:13834 ppid:7473 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x1553/0x45a0 kernel/sched/core.c:6700
preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6867
preempt_schedule+0xc0/0xd0 kernel/sched/core.c:6891
preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45
unwind_next_frame+0x200f/0x2970 arch/x86/kernel/unwind_orc.c:672
arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122
save_stack+0x125/0x230 mm/page_owner.c:128
__reset_page_owner+0x4e/0x190 mm/page_owner.c:149
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1181 [inline]
free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365
free_unref_page_list+0xbe/0x860 mm/page_alloc.c:2504
release_pages+0x1f7a/0x2200 mm/swap.c:1022
__folio_batch_release+0x71/0xe0 mm/swap.c:1042
folio_batch_release include/linux/pagevec.h:83 [inline]
shmem_undo_range+0x630/0x1b20 mm/shmem.c:1026
shmem_truncate_range mm/shmem.c:1135 [inline]
shmem_evict_inode+0x245/0x9e0 mm/shmem.c:1264
evict+0x4ca/0x8d0 fs/inode.c:705
__dentry_kill+0x431/0x650 fs/dcache.c:611
dentry_kill+0xb8/0x290 fs/dcache.c:-1
dput+0xfe/0x1e0 fs/dcache.c:918
__fput+0x5e5/0x970 fs/file_table.c:392
task_work_run+0x1d4/0x260 kernel/task_work.c:245
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0x95a/0x2460 kernel/exit.c:883
do_group_exit+0x21b/0x2d0 kernel/exit.c:1024
get_signal+0x12fc/0x13f0 kernel/signal.c:2902
arch_do_signal_or_restart+0xc2/0x800 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
irqentry_exit_to_user_mode+0x9/0x30 kernel/entry/common.c:315
exc_page_fault+0x8c/0x100 arch/x86/mm/fault.c:1519
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7f486ef9c631
RSP: 002b:fffffffffffffe70 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f486f215fa0 RCX: 00007f486ef9c629
RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000
RBP: 00007f486f032b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f486f216038 R14: 00007f486f215fa0 R15: 00007ffd70375598
task:syz.6.2093 state:R running task stack:25768 pid:13930 ppid:11551 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x1553/0x45a0 kernel/sched/core.c:6700
preempt_schedule_irq+0xbf/0x150 kernel/sched/core.c:7010
irqentry_exit+0x67/0x70 kernel/entry/common.c:438
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:debug_lockdep_rcu_enabled+0x22/0x30 kernel/rcu/update.c:320
Code: cc cc cc cc cc cc cc cc f3 0f 1e fa 31 c0 83 3d 4f 6d 06 04 00 74 1d 83 3d d6 a0 06 04 00 74 14 65 48 8b 0d 20 43 7f 75 31 c0 <83> b9 dc 0a 00 00 00 0f 94 c0 c3 cc cc cc 66 0f 1f 00 48 8b 3c 24
RSP: 0018:ffffc900037674c0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffffff81e72a49 RCX: ffff888024999e00
RDX: 0000000000000000 RSI: ffffffff8b1c82c0 RDI: ffffffff8b1c8280
RBP: 0000000000000cc0 R08: dffffc0000000000 R09: 1ffffffff2237ea0
R10: dffffc0000000000 R11: fffffbfff2237ea1 R12: ffffea000155de48
R13: dffffc0000000000 R14: ffff88806cc3a010 R15: dffffc0000000000
rcu_read_unlock include/linux/rcupdate.h:815 [inline]
percpu_ref_put_many include/linux/percpu-refcount.h:337 [inline]
percpu_ref_put+0xac/0x180 include/linux/percpu-refcount.h:351
css_put include/linux/cgroup_refcnt.h:79 [inline]
__mem_cgroup_charge+0x56/0x80 mm/memcontrol.c:7112
mem_cgroup_charge include/linux/memcontrol.h:686 [inline]
shmem_add_to_page_cache+0x904/0x1b30 mm/shmem.c:784
shmem_get_folio_gfp+0xf08/0x2aa0 mm/shmem.c:2071
shmem_fault+0x1b8/0x810 mm/shmem.c:2248
__do_fault+0x13b/0x4d0 mm/memory.c:4244
do_read_fault mm/memory.c:4638 [inline]
do_fault mm/memory.c:4775 [inline]
do_pte_missing mm/memory.c:3689 [inline]
handle_pte_fault mm/memory.c:5047 [inline]
__handle_mm_fault mm/memory.c:5188 [inline]
handle_mm_fault+0x2299/0x4c00 mm/memory.c:5353
faultin_page mm/gup.c:868 [inline]
__get_user_pages+0x5d0/0x1380 mm/gup.c:1167
populate_vma_page_range+0x2c1/0x380 mm/gup.c:1593
__mm_populate+0x260/0x390 mm/gup.c:1696
mm_populate include/linux/mm.h:3383 [inline]
vm_mmap_pgoff+0x2da/0x3f0 mm/util.c:561
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7efeaad9c629
RSP: 002b:00007efeabcaa028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007efeab015fa0 RCX: 00007efeaad9c629
RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007efeaae32b39 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 00007efeab016038 R14: 00007efeab015fa0 R15: 00007ffcf32ef418
rcu: rcu_preempt kthread starved for 10565 jiffies! g75213 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:27720 pid:17 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x1553/0x45a0 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168
rcu_gp_fqs_loop+0x313/0x1590 kernel/rcu/tree.c:1667
rcu_gp_kthread+0x9d/0x3b0 kernel/rcu/tree.c:1866
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:arch_irqs_disabled_flags arch/x86/include/asm/irqflags.h:126 [inline]
RIP: 0010:seqcount_lockdep_reader_access+0xa0/0x1d0 include/linux/seqlock.h:101
Code: c7 44 24 40 00 00 00 00 9c 8f 44 24 40 4c 8b 64 24 40 43 c6 44 3e 08 f8 fa 4c 89 e6 48 81 e6 00 02 00 00 31 ff e8 d0 c9 0f 00 <49> 81 e4 00 02 00 00 75 3d e8 82 c5 0f 00 48 8b 5d 08 48 c7 c7 08
RSP: 0018:ffffc90000007e20 EFLAGS: 00000006
RAX: ffffffff81774f80 RBX: 0000000000000000 RCX: ffffffff8ce93440
RDX: 0000000000010000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000007ed0 R08: ffffffff9730b367 R09: 1ffffffff2e6166c
R10: dffffc0000000000 R11: fffffbfff2e6166d R12: 0000000000000006
R13: 1ffff110171c5808 R14: 1ffff92000000fc4 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2dcfe9 CR3: 000000001bfa6000 CR4: 00000000003506f0
Call Trace:
ktime_get+0x35/0x280 kernel/time/timekeeping.c:846
tick_nohz_irq_enter kernel/time/tick-sched.c:1439 [inline]
tick_irq_enter+0xf2/0x310 kernel/time/tick-sched.c:1467
irq_enter_rcu+0x9e/0xf0 kernel/softirq.c:624
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0x97/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:pv_native_safe_halt+0xf/0x10 arch/x86/kernel/paravirt.c:148
Code: c7 22 02 c3 cc cc cc cc cc cc cc f3 0f 1e fa 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 66 90 0f 00 2d 83 d1 43 00 fb f4 66 0f 1f 00 55 41 57 41 56 41 54 53 50 8b 2f eb 2e 41 89 de 80
RSP: 0018:ffffffff8ce07d80 EFLAGS: 000002c2
RAX: b363a392c4ec7100 RBX: ffffffff8162a490 RCX: b363a392c4ec7100
RDX: 0000000000000001 RSI: ffffffff8acac900 RDI: ffffffff8b1c82e0
RBP: ffffffff8ce07eb8 R08: ffff8880b8e36b2b R09: 1ffff110171c6d65
R10: dffffc0000000000 R11: ffffed10171c6d66 R12: 1ffffffff19d2688
R13: 1ffffffff19c0fbc R14: 0000000000000000 R15: dffffc0000000000
arch_safe_halt arch/x86/include/asm/paravirt.h:108 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:753
default_idle_call+0x6c/0xa0 kernel/sched/idle.c:97
cpuidle_idle_call kernel/sched/idle.c:170 [inline]
do_idle+0x1f0/0x4e0 kernel/sched/idle.c:282
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:380
rest_init+0x2e2/0x300 init/main.c:744
arch_call_rest_init+0xe/0x10 init/main.c:841
start_kernel+0x459/0x4e0 init/main.c:1086
x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:555
x86_64_start_kernel+0x60/0x60 arch/x86/kernel/head64.c:536
secondary_startup_64_no_verify+0x179/0x17b