rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P3472/1:b..l P14680/1:b..l
rcu: (detected by 1, t=10503 jiffies, g=60765, q=34 ncpus=2)
task:syz.3.2146 state:R running task stack:26120 pid:14680 tgid:14679 ppid:5830 task_flags:0x40044c flags:0x00080002
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:orc_ip arch/x86/kernel/unwind_orc.c:80 [inline]
RIP: 0010:__orc_find+0x65/0xf0 arch/x86/kernel/unwind_orc.c:102
Code: eb 0c 48 8d 6b 04 49 89 df 49 39 ec 72 4e 4c 89 e2 48 29 ea 48 89 d6 48 c1 ea 3f 48 c1 fe 02 48 01 f2 48 d1 fa 48 8d 5c 95 00 <48> 89 da 48 c1 ea 03 0f b6 34 0a 48 89 da 83 e2 07 83 c2 03 40 38
RSP: 0000:ffffc9000be86df0 EFLAGS: 00000247
RAX: ffffffff912e8bac RBX: ffffffff90a5f134 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff90a5f12c
RBP: ffffffff90a5f134 R08: ffffffff912e8be2 R09: 00000000b19a5ccf
R10: ffff888026f854b0 R11: 00000000000130fd R12: ffffffff90a5f138
R13: ffffffff8230fd4f R14: ffffffff90a5f12c R15: ffffffff90a5f130
orc_find arch/x86/kernel/unwind_orc.c:227 [inline]
unwind_next_frame+0x2ec/0x20a0 arch/x86/kernel/unwind_orc.c:494
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:156
__reset_page_owner+0x84/0x1a0 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+0xa15/0x1600 mm/page_alloc.c:2958
folios_put_refs+0x4be/0x750 mm/swap.c:1002
free_pages_and_swap_cache+0x245/0x4a0 mm/swap_state.c:355
__tlb_batch_free_encoded_pages+0xf9/0x290 mm/mmu_gather.c:136
tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
tlb_flush_mmu_free mm/mmu_gather.c:397 [inline]
tlb_flush_mmu+0xe9/0x5a0 mm/mmu_gather.c:404
zap_pte_range mm/memory.c:1894 [inline]
zap_pmd_range mm/memory.c:1947 [inline]
zap_pud_range mm/memory.c:1976 [inline]
zap_p4d_range mm/memory.c:1997 [inline]
unmap_page_range+0x1d47/0x4030 mm/memory.c:2018
unmap_single_vma.constprop.0+0x153/0x240 mm/memory.c:2061
unmap_vmas+0x218/0x470 mm/memory.c:2105
exit_mmap+0x1b2/0xb60 mm/mmap.c:1280
__mmput+0x12a/0x410 kernel/fork.c:1130
mmput+0x62/0x70 kernel/fork.c:1153
exit_mm kernel/exit.c:583 [inline]
do_exit+0x7d7/0x2bd0 kernel/exit.c:961
do_group_exit+0xd3/0x2a0 kernel/exit.c:1114
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+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: 0033:0x7f5a6698f749
RSP: 002b:00007f5a6778c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: 000000000000000b RBX: 00007f5a66be5fa0 RCX: 00007f5a6698f749
RDX: 0000000000000318 RSI: 00002000000bd000 RDI: 0000000000000004
RBP: 00007f5a66a13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5a66be6038 R14: 00007f5a66be5fa0 R15: 00007fffd6aa3aa8
task:kworker/u8:11 state:R running task stack:21960 pid:3472 tgid:3472 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: krdsd rds_connect_worker
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:lock_release+0x183/0x2d0 kernel/locking/lockdep.c:5893
Code: 0f c1 05 b8 7a 12 12 83 f8 01 0f 85 03 01 00 00 9c 58 f6 c4 02 0f 85 ee 00 00 00 41 f7 c5 00 02 00 00 74 01 fb 48 8b 44 24 10 <65> 48 2b 05 4d 34 12 12 0f 85 32 01 00 00 48 83 c4 18 5b 41 5c 41
RSP: 0000:ffffc9000ca17498 EFLAGS: 00000206
RAX: 2f048f94dfeeed00 RBX: ffffffff8e3c92c0 RCX: ffffc9000ca174a4
RDX: 0000000000000002 RSI: ffffffff8da9585e RDI: ffffffff8bf21180
RBP: 0000000000000001 R08: 0000000000000001 R09: 00000000e3a0519a
R10: ffff8880328f54b0 R11: 0000000000008402 R12: ffffffff816c2504
R13: 0000000000000206 R14: ffff8880328f4980 R15: 0000000000000003
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:897 [inline]
class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0x3f9/0x20a0 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
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:587
kasan_save_free_info mm/kasan/kasan.h:406 [inline]
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:6663 [inline]
kfree+0x2f8/0x6e0 mm/slub.c:6871
security_sk_free+0x9d/0x1a0 security/security.c:4410
sk_prot_free net/core/sock.c:2277 [inline]
__sk_destruct+0x4c6/0x910 net/core/sock.c:2384
sk_destruct+0xc2/0xf0 net/core/sock.c:2412
__sk_free+0xf4/0x3e0 net/core/sock.c:2423
sk_free+0x6a/0x90 net/core/sock.c:2434
sock_put include/net/sock.h:1998 [inline]
tcp_close+0xd3/0x120 net/ipv4/tcp.c:3303
inet_release+0xed/0x200 net/ipv4/af_inet.c:437
__sock_release net/socket.c:653 [inline]
sock_release+0x91/0x1d0 net/socket.c:681
rds_tcp_conn_path_connect+0x4aa/0x7f0 net/rds/tcp_connect.c:191
rds_connect_worker+0x1af/0x2c0 net/rds/threads.c:176
process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
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: rcu_preempt kthread starved for 10592 jiffies! g60765 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:27792 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:
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:__sanitizer_cov_trace_pc+0x66/0x70 kernel/kcov.c:235
Code: 82 48 16 00 00 83 f8 02 75 20 48 8b 8a 50 16 00 00 8b 92 4c 16 00 00 48 8b 01 48 83 c0 01 48 39 d0 73 07 48 89 01 48 89 34 c1 cc cc cc cc 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8e007c98 EFLAGS: 00000093
RAX: 0000000000000000 RBX: ffff8880b8428ca0 RCX: ffffffff81aeaec6
RDX: ffffffff8e097a80 RSI: ffffffff81aea378 RDI: ffff8880b8428ca0
RBP: 1ffffffff1c00faf R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 00000000ffffffff R12: dffffc0000000000
R13: 1ffffffff1c00f95 R14: ffffffff9086e4d0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888124968000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b344d6ff8 CR3: 0000000066195000 CR4: 00000000003526f0
Call Trace:
tick_nohz_next_event+0x68/0x400 kernel/time/tick-sched.c:916
tick_nohz_idle_stop_tick+0x7bf/0xe50 kernel/time/tick-sched.c:1239
cpuidle_idle_call kernel/sched/idle.c:189 [inline]
do_idle+0x388/0x510 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+0x3f6/0x4d0 init/main.c:1111
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