rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6641/3:b..l P10380/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=35797, q=215 ncpus=2)
task:syz.2.1216 state:R running task stack:24912 pid:10380 tgid:10378 ppid:5846 task_flags:0x40054c flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256
irqentry_exit+0x6f/0x90 kernel/entry/common.c:211
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0xa64/0x2390 arch/x86/kernel/unwind_orc.c:-1
Code: 48 89 d0 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 82 17 00 00 48 89 d8 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 99 17 00 00 48 0f bf 02 <49> 01 c4 48 8d 5e 01 48 8b 44 24 40 0f b6 04 28 84 c0 0f 85 78 13
RSP: 0018:ffffc90003cded18 EFLAGS: 00000246
RAX: 0000000000000060 RBX: ffffffff900a9803 RCX: ffffffff8f903dd4
RDX: ffffffff900a9802 RSI: ffffffff900a9806 RDI: ffffffff8bbf0400
RBP: dffffc0000000000 R08: 0000000000000009 R09: ffffffff81738d25
R10: dffffc0000000000 R11: fffff5200079bdd5 R12: ffffc90003cdede8
R13: ffffc90003cdee98 R14: ffffc90003cdee48 R15: ffffc90003cdee80
__unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf5/0x1f0 mm/page_owner.c:156
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:311
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1394 [inline]
free_unref_folios+0xdb3/0x14f0 mm/page_alloc.c:2963
folios_put_refs+0x584/0x670 mm/swap.c:1002
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x49e/0x14b0 mm/shmem.c:1120
shmem_truncate_range mm/shmem.c:1232 [inline]
shmem_evict_inode+0x272/0xa70 mm/shmem.c:1360
evict+0x504/0x9c0 fs/inode.c:810
__dentry_kill+0x209/0x660 fs/dcache.c:669
dput+0x19f/0x2b0 fs/dcache.c:911
__fput+0x68e/0xa70 fs/file_table.c:476
task_work_run+0x1d4/0x260 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x6b5/0x2300 kernel/exit.c:966
do_group_exit+0x21c/0x2d0 kernel/exit.c:1107
get_signal+0x1285/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0xa0/0x790 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x72/0x130 kernel/entry/common.c:40
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f320178efc9
RSP: 002b:00007f320266a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: 000000000000000b RBX: 00007f32019e5fa0 RCX: 00007f320178efc9
RDX: 0000000000000651 RSI: 0000200000000000 RDI: 0000000000000005
RBP: 00007f3201811f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f32019e6038 R14: 00007f32019e5fa0 R15: 00007ffea95b7d08
task:kworker/u8:11 state:R running task stack:20800 pid:6641 tgid:6641 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: krdsd rds_tcp_accept_worker
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7113
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7137
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__local_bh_enable_ip+0x13e/0x1c0 kernel/softirq.c:457
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:936 [inline]
__dev_queue_xmit+0x1d79/0x3b50 net/core/dev.c:4790
dev_queue_xmit include/linux/netdevice.h:3365 [inline]
neigh_hh_output include/net/neighbour.h:531 [inline]
neigh_output include/net/neighbour.h:545 [inline]
ip6_finish_output2+0xf70/0x1480 net/ipv6/ip6_output.c:136
NF_HOOK_COND include/linux/netfilter.h:307 [inline]
ip6_output+0x340/0x550 net/ipv6/ip6_output.c:247
NF_HOOK include/linux/netfilter.h:318 [inline]
ip6_xmit+0x11b5/0x1970 net/ipv6/ip6_output.c:371
inet6_csk_xmit+0x4db/0x780 net/ipv6/inet6_connection_sock.c:120
__tcp_transmit_skb+0x2092/0x3aa0 net/ipv4/tcp_output.c:1628
tcp_transmit_skb net/ipv4/tcp_output.c:1646 [inline]
tcp_write_xmit+0x16e8/0x6940 net/ipv4/tcp_output.c:2999
__tcp_push_pending_frames+0x97/0x360 net/ipv4/tcp_output.c:3182
__tcp_close+0x617/0xfe0 net/ipv4/tcp.c:3207
tcp_close+0x28/0x110 net/ipv4/tcp.c:3298
inet_release+0x144/0x190 net/ipv4/af_inet.c:437
__sock_release net/socket.c:662 [inline]
sock_release+0x85/0x150 net/socket.c:690
rds_tcp_accept_one+0x71a/0x930 net/rds/tcp_listen.c:214
rds_tcp_accept_worker+0x3e/0xa0 net/rds/tcp.c:529
process_one_work kernel/workqueue.c:3263 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: rcu_preempt kthread starved for 10332 jiffies! g35797 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:27192 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7026
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
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 10/02/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: 5e 33 ca f5 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 33 21 22 00 f3 0f 1e fa fb f4 33 33 ca f5 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8dc07d80 EFLAGS: 000002c6
RAX: c661fddccdf15700 RBX: ffffffff81967b87 RCX: c661fddccdf15700
RDX: 0000000000000001 RSI: ffffffff8d70bd6a RDI: ffffffff8bbf0460
RBP: ffffffff8dc07ea8 R08: ffff8880b8832fdb R09: 1ffff110171065fb
R10: dffffc0000000000 R11: ffffed10171065fc R12: ffffffff8f7cd370
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1b92a40
FS: 0000000000000000(0000) GS:ffff88812613e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555564687808 CR3: 0000000065364000 CR4: 0000000000350ef0
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+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:190 [inline]
do_idle+0x1e7/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
rest_init+0x2de/0x300 init/main.c:757
start_kernel+0x3ae/0x410 init/main.c:1111
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