rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6471/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=13933, q=1004 ncpus=2)
task:kworker/u8:11 state:R running task stack:26744 pid:6471 tgid:6471 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: iou_exit io_ring_exit_work
Call Trace:
context_switch kernel/sched/core.c:5401 [inline]
__schedule+0x116a/0x5de0 kernel/sched/core.c:6790
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7113
irqentry_exit+0x36/0x90 kernel/entry/common.c:307
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:unwind_next_frame+0x5c1/0x20a0 arch/x86/kernel/unwind_orc.c:515
Code: 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 38 d0 7f 08 84 c0 0f 85 aa 13 00 00 45 88 7d 35 <44> 0f b6 71 04 41 83 e6 0f 41 80 fe 06 0f 84 c4 0a 00 00 0f 87 20
RSP: 0018:ffffc9000434f5d8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff914c6948
RDX: 0000000000000005 RSI: 0000000000000001 RDI: ffffffff90c3b68c
RBP: ffffc9000434f690 R08: ffffffff914c694c R09: 0000000000000000
R10: 0000000000000000 R11: 000000000001180a R12: ffffc9000434f698
R13: ffffc9000434f648 R14: ffffc9000434f67d R15: 0000000000000000
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:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:905 [inline]
slab_free_hook mm/slub.c:2333 [inline]
slab_free mm/slub.c:4643 [inline]
kmem_cache_free+0x142/0x4d0 mm/slub.c:4745
__io_req_caches_free+0x90/0x3d0 io_uring/io_uring.c:2709
io_req_caches_free io_uring/io_uring.c:2721 [inline]
io_ring_exit_work+0x3b9/0x1120 io_uring/io_uring.c:2919
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3321 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
kthread+0x3c5/0x780 kernel/kthread.c:464
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g13933 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=9528
rcu: rcu_preempt kthread starved for 10502 jiffies! g13933 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:28744 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5401 [inline]
__schedule+0x116a/0x5de0 kernel/sched/core.c:6790
__schedule_loop kernel/sched/core.c:6868 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6883
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2054
rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2256
kthread+0x3c5/0x780 kernel/kthread.c:464
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
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: 15 Comm: ksoftirqd/0 Not tainted 6.16.0-rc5-syzkaller-00224-g379f604cc3dc #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:enqueue_hrtimer+0xbe/0x3b0 kernel/time/hrtimer.c:1089
Code: 13 00 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 cc 02 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b 23 <49> 8d 7c 24 4c 48 89 fa 48 c1 ea 03 0f b6 04 02 48 89 fa 83 e2 07
RSP: 0018:ffffc90000007e18 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: ffff8880b8427d80 RCX: ffffffff81a8e07f
RDX: 1ffff11017084fb0 RSI: ffffffff81a8de36 RDI: 0000000000000001
RBP: ffff888036561340 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffff9affe120 R12: ffff8880b8427c80
R13: 0000000000000000 R14: ffff888036561340 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888124713000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd5e492da90 CR3: 0000000049415000 CR4: 00000000003526f0
Call Trace:
__run_hrtimer kernel/time/hrtimer.c:1778 [inline]
__hrtimer_run_queues+0x8ff/0xad0 kernel/time/hrtimer.c:1825
hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
__sysvec_apic_timer_interrupt+0x10b/0x3f0 arch/x86/kernel/apic/apic.c:1056
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5875
Code: 41 38 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 62 fa 10 0f 0f 82 74 02 00 00 8b 35 4a 2c 11 0f 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 f9 40 38 12 0f 85 c7 02 00 00 48 83 c4
RSP: 0018:ffffc90000147730 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e5c4e80 RCX: 0000000093ae86fb
RDX: 0000000000000000 RSI: ffffffff8de0da05 RDI: ffffffff8c158fa0
RBP: 0000000000000002 R08: 19fc8a606420ad85 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xd1/0x20a0 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:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2381 [inline]
slab_free mm/slub.c:4643 [inline]
kfree+0x2b4/0x4d0 mm/slub.c:4842
slab_free_after_rcu_debug+0x60/0x340 mm/slub.c:4680
rcu_do_batch kernel/rcu/tree.c:2576 [inline]
rcu_core+0x79c/0x14e0 kernel/rcu/tree.c:2832
handle_softirqs+0x219/0x8e0 kernel/softirq.c:579
run_ksoftirqd kernel/softirq.c:968 [inline]
run_ksoftirqd+0x3a/0x60 kernel/softirq.c:960
smpboot_thread_fn+0x3f7/0xae0 kernel/smpboot.c:164
kthread+0x3c5/0x780 kernel/kthread.c:464
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245