rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6955/1:b..l P6855/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=12541, q=361 ncpus=2)
task:syz.4.222 state:R running task stack:23208 pid:6855 tgid:6855 ppid:5812 task_flags:0x40064c flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0x59b/0x20a0 arch/x86/kernel/unwind_orc.c:512
Code: 00 41 83 e7 07 44 38 f8 0f 9e c2 84 c0 0f 95 c0 84 c2 0f 85 d7 13 00 00 4c 89 f2 44 0f b6 79 05 48 b8 00 00 00 00 00 fc ff df <48> c1 ea 03 0f b6 04 02 4c 89 f2 41 c0 ef 03 83 e2 07 41 83 e7 01
RSP: 0018:ffffc9001b2bef38 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffffff9131aa5a
RDX: ffffc9001b2befdd RSI: 0000000000000001 RDI: ffffffff90a8a558
RBP: ffffc9001b2beff0 R08: ffffffff9131aa5e R09: 00000000ffffffff
R10: 0000000000000002 R11: 000000000001434b R12: ffffc9001b2beff8
R13: ffffc9001b2befa8 R14: ffffc9001b2befdd R15: 0000000000000002
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
save_stack+0x160/0x1f0 mm/page_owner.c:165
__reset_page_owner+0x84/0x1a0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1395 [inline]
free_unref_folios+0xa22/0x1610 mm/page_alloc.c:3000
folios_put_refs+0x4be/0x750 mm/swap.c:1002
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x58f/0x1140 mm/shmem.c:1137
shmem_truncate_range mm/shmem.c:1249 [inline]
shmem_evict_inode+0x39e/0xbe0 mm/shmem.c:1379
evict+0x3c2/0xad0 fs/inode.c:837
iput_final fs/inode.c:1951 [inline]
iput.part.0+0x621/0x1190 fs/inode.c:2003
iput+0x35/0x40 fs/inode.c:1966
dentry_unlink_inode+0x29c/0x480 fs/dcache.c:467
__dentry_kill+0x1d0/0x600 fs/dcache.c:670
finish_dput+0x76/0x480 fs/dcache.c:879
dput.part.0+0x451/0x570 fs/dcache.c:928
dput+0x1f/0x30 fs/dcache.c:920
__fput+0x51c/0xb70 fs/file_table.c:476
task_work_run+0x150/0x240 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x87f/0x2bd0 kernel/exit.c:971
do_group_exit+0xd3/0x2a0 kernel/exit.c:1112
get_signal+0x2671/0x26d0 kernel/signal.c:3034
arch_do_signal_or_restart+0x8f/0x7e0 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+0x38a/0x8c0 kernel/entry/common.c:196
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7fe31878f751
RSP: 002b:fffffffffffffe70 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fe3189e5fa0 RCX: 00007fe31878f749
RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000
RBP: 00007fe318813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fe3189e6038 R14: 00007fe3189e5fa0 R15: 00007ffcf87ac288
task:syz.1.250 state:R running task stack:26376 pid:6955 tgid:6952 ppid:5813 task_flags:0x400140 flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x62/0x330 kernel/locking/lockdep.c:5872
Code: 36 18 12 83 f8 07 0f 87 a2 02 00 00 89 c0 48 0f a3 05 82 83 ee 0e 0f 82 74 02 00 00 8b 35 1a b4 ee 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 99 36 18 12 0f 85 ad 02 00 00 48 83 c4
RSP: 0018:ffffc9000d9274a0 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e3c9620 RCX: 00000000c5f182be
RDX: 0000000000000000 RSI: ffffffff8daa563c RDI: ffffffff8bf2a580
RBP: 0000000000000002 R08: 000000003cb5b09f R09: 00000000f3cb5b09
R10: 0000000000000002 R11: ffff88802d2f2ff0 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
is_bpf_text_address+0x36/0x1a0 kernel/bpf/core.c:744
kernel_text_address kernel/extable.c:125 [inline]
kernel_text_address+0x8d/0x100 kernel/extable.c:94
__kernel_text_address+0xd/0x40 kernel/extable.c:79
unwind_get_return_address+0x59/0xa0 arch/x86/kernel/unwind_orc.c:369
arch_stack_walk+0xa6/0x100 arch/x86/kernel/stacktrace.c:26
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
kasan_save_track+0x14/0x30 mm/kasan/common.c:77
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:252 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284
kasan_slab_free include/linux/kasan.h:234 [inline]
slab_free_hook mm/slub.c:2540 [inline]
slab_free mm/slub.c:6668 [inline]
kfree+0x2f8/0x6e0 mm/slub.c:6876
skb_kfree_head net/core/skbuff.c:1068 [inline]
skb_free_head+0x114/0x210 net/core/skbuff.c:1080
skb_release_data+0x795/0x9e0 net/core/skbuff.c:1107
skb_release_all net/core/skbuff.c:1182 [inline]
__kfree_skb net/core/skbuff.c:1196 [inline]
sk_skb_reason_drop+0x129/0x1a0 net/core/skbuff.c:1234
kfree_skb_reason include/linux/skbuff.h:1322 [inline]
unix_release_sock+0x797/0x1460 net/unix/af_unix.c:726
unix_release+0x91/0xf0 net/unix/af_unix.c:1184
__sock_release+0xb3/0x270 net/socket.c:662
sock_close+0x1c/0x30 net/socket.c:1455
__fput+0x402/0xb70 fs/file_table.c:468
task_work_run+0x150/0x240 kernel/task_work.c:233
get_signal+0x1d0/0x26d0 kernel/signal.c:2807
arch_do_signal_or_restart+0x8f/0x7e0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop+0x8c/0x540 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x4ee/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f03ced8f749
RSP: 002b:00007f03cfbbe038 EFLAGS: 00000246 ORIG_RAX: 000000000000010e
RAX: 0000000000000001 RBX: 00007f03cefe6180 RCX: 00007f03ced8f749
RDX: 0000000000000000 RSI: 0000200000000040 RDI: 0000000000000040
RBP: 00007f03cee13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000100 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f03cefe6218 R14: 00007f03cefe6180 R15: 00007ffc2c9e26c8
rcu: rcu_preempt kthread starved for 10599 jiffies! g12541 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:28696 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 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:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: 36 60 02 c3 cc cc cc cc 0f 1f 00 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 13 e9 12 00 fb f4 cc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e007df8 EFLAGS: 000002c6
RAX: 00000000005df357 RBX: 0000000000000000 RCX: ffffffff8b7776d9
RDX: 0000000000000000 RSI: ffffffff8dacb6cd RDI: ffffffff8bf2a580
RBP: fffffbfff1c12f68 R08: 0000000000000001 R09: ffffed101708673d
R10: ffff8880b84339eb R11: ffffffff8e098670 R12: 0000000000000000
R13: ffffffff8e097b40 R14: ffffffff90887cd0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881248fd000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30206ff8 CR3: 00000000763f0000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x38d/0x510 kernel/sched/idle.c:332
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430
rest_init+0x16b/0x2b0 init/main.c:757
start_kernel+0x3ef/0x4d0 init/main.c:1206
x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x148