rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=9dd4/1/0x4000000000000000 softirq=40935/40936 fqs=0
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P48/1:b..l
rcu: (detected by 1, t=10505 jiffies, g=32317, q=5378 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5833 Comm: syz-executor Not tainted 6.16.0-rc5-syzkaller-00121-gbc9ff192a6c9 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:advance_sched+0x3e9/0xc90 net/sched/sch_taprio.c:-1
Code: 4c 8b 3c 24 4c 89 e0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 4c 89 e7 e8 0e e9 99 f8 49 8b 87 10 01 00 00 <48> 89 44 24 28 4d 8d b7 28 01 00 00 4c 89 f0 48 c1 e8 03 49 bc 00
RSP: 0018:ffffc90000007c70 EFLAGS: 00000046
RAX: ffff888056713540 RBX: 0000000000000000 RCX: dffffc0000000000
RDX: 0000000000010000 RSI: 0000000000000000 RDI: 185ab44718000000
RBP: 0000000000000002 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000f7c R12: ffff888056712d10
R13: ffff8880288f2000 R14: 185ab44718000000 R15: ffff888056712c00
FS: 000055557cb6c500(0000) GS:ffff888125c4f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2b7b62 CR3: 00000000738b0000 CR4: 00000000003526f0
Call Trace:
__run_hrtimer kernel/time/hrtimer.c:1761 [inline]
__hrtimer_run_queues+0x52c/0xc60 kernel/time/hrtimer.c:1825
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
__sysvec_apic_timer_interrupt+0x108/0x410 arch/x86/kernel/apic/apic.c:1056
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 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+0x175/0x360 kernel/locking/lockdep.c:5875
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 ab d1 fe 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9000418f2e8 EFLAGS: 00000206
RAX: caf8784c1cf07a00 RBX: 0000000000000000 RCX: caf8784c1cf07a00
RDX: 0000000000000000 RSI: ffffffff8db71d8d RDI: ffffffff8be1ca40
RBP: ffffffff822cb2cd R08: 0000000000000000 R09: ffffffff822cb2cd
R10: dffffc0000000000 R11: fffff94000350121 R12: 0000000000000002
R13: ffffffff8e13f160 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
page_table_check_set+0x1aa/0x730 mm/page_table_check.c:112
page_table_check_ptes_set include/linux/page_table_check.h:76 [inline]
set_ptes include/linux/pgtable.h:292 [inline]
__copy_present_ptes mm/memory.c:973 [inline]
copy_present_ptes mm/memory.c:1056 [inline]
copy_pte_range mm/memory.c:1179 [inline]
copy_pmd_range+0x4262/0x7000 mm/memory.c:1267
copy_pud_range mm/memory.c:1304 [inline]
copy_p4d_range mm/memory.c:1328 [inline]
copy_page_range+0xc46/0x1270 mm/memory.c:1416
dup_mmap+0xf57/0x1ac0 mm/mmap.c:1838
dup_mm kernel/fork.c:1477 [inline]
copy_mm+0x13c/0x4b0 kernel/fork.c:1529
copy_process+0x16d3/0x3b80 kernel/fork.c:2169
kernel_clone+0x224/0x7f0 kernel/fork.c:2599
__do_sys_clone kernel/fork.c:2742 [inline]
__se_sys_clone kernel/fork.c:2726 [inline]
__x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2726
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3ab6985193
Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00
RSP: 002b:00007ffe09a3cb08 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3ab6985193
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 000055557cb6c7d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 00000000000536b9 R15: 00007ffe09a3cca0
task:kworker/u8:3 state:R running task stack:21992 pid:48 tgid:48 ppid:2 task_flags:0x4208160 flags:0x00004000
Workqueue: iou_exit io_ring_exit_work
Call Trace:
context_switch kernel/sched/core.c:5401 [inline]
__schedule+0x16a2/0x4cb0 kernel/sched/core.c:6790
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7113
irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0xb9/0x360 kernel/locking/lockdep.c:5847
Code: 9c bd 02 0e 00 0f 84 fa 00 00 00 65 8b 05 9f 12 ff 10 85 c0 0f 85 eb 00 00 00 65 48 8b 04 25 08 10 9d 92 83 b8 ec 0a 00 00 00 <0f> 85 d5 00 00 00 48 c7 44 24 30 00 00 00 00 9c 8f 44 24 30 4c 89
RSP: 0018:ffffc90000b87338 EFLAGS: 00000246
RAX: ffff88801be99e00 RBX: 0000000000000000 RCX: 885d34bbe7e95900
RDX: 0000000000000000 RSI: ffffffff8172ab02 RDI: 1ffffffff1c27e2c
RBP: ffffffff8172aae5 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc90000b874f8 R11: ffffffff81ad0290 R12: 0000000000000002
R13: ffffffff8e13f160 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+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack+0x3e/0x60 mm/kasan/common.c:47
kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:548
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4643 [inline]
kmem_cache_free+0x2f6/0x400 mm/slub.c:4745
__io_req_caches_free+0x8f/0x140 io_uring/io_uring.c:2710
io_req_caches_free+0x21/0x30 io_uring/io_uring.c:2722
io_ring_exit_work+0x415/0x930 io_uring/io_uring.c:2920
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: rcu_preempt kthread starved for 10505 jiffies! g32317 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:27320 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5401 [inline]
__schedule+0x16a2/0x4cb0 kernel/sched/core.c:6790
__schedule_loop kernel/sched/core.c:6868 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6883
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 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:
CPU: 1 UID: 0 PID: 9457 Comm: syz.4.1063 Not tainted 6.16.0-rc5-syzkaller-00121-gbc9ff192a6c9 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0xf69/0x12d0 kernel/smp.c:885
Code: 00 45 8b 2f 44 89 ee 83 e6 01 31 ff e8 c0 78 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 6b 74 0b 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 50 74 0b
RSP: 0018:ffffc9001ab974a0 EFLAGS: 00000293
RAX: ffffffff81b4c100 RBX: ffff8880b873b040 RCX: ffff888027b41e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9001ab97600 R08: ffffffff8fa0c9f7 R09: 1ffffffff1f4193e
R10: dffffc0000000000 R11: ffffffff81704100 R12: 1ffff110170c835d
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b8641ae8
FS: 0000000000000000(0000) GS:ffff888125d4f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff59850ef98 CR3: 0000000073802000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052
__flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
flush_tlb_mm_range+0x6b1/0x12c0 arch/x86/mm/tlb.c:1451
tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:490 [inline]
tlb_flush_mmu+0x1a7/0x680 mm/mmu_gather.c:403
tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497
exit_mmap+0x44c/0xb50 mm/mmap.c:1297
__mmput+0x118/0x410 kernel/fork.c:1121
exit_mm+0x1da/0x2c0 kernel/exit.c:581
do_exit+0x648/0x22e0 kernel/exit.c:952
do_group_exit+0x21c/0x2d0 kernel/exit.c:1105
get_signal+0x125e/0x1310 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8f9f38e929
Code: Unable to access opcode bytes at 0x7f8f9f38e8ff.
RSP: 002b:00007f8fa02a50e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f8f9f5b5fa8 RCX: 00007f8f9f38e929
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f8f9f5b5fa8
RBP: 00007f8f9f5b5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8f9f5b5fac
R13: 0000000000000000 R14: 00007ffe1b1e7390 R15: 00007ffe1b1e7478