rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (4 ticks this GP) idle=0dcc/1/0x4000000000000000 softirq=131906/131907 fqs=2
rcu: (detected by 1, t=10506 jiffies, g=110217, q=234 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 22650 Comm: syz.2.4041 Not tainted 6.16.0-rc1-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__lock_acquire+0x622/0x1c90 kernel/locking/lockdep.c:5237
Code: 30 8b 4c 24 38 4c 8b 64 24 40 44 8b 15 c7 df 0f 0f 45 85 d2 75 23 85 db 0f 85 66 04 00 00 4c 89 ef 89 4c 24 08 e8 9e ac ff ff <8b> 4c 24 08 48 83 78 40 00 0f 84 a1 0a 00 00 0f b7 44 24 10 8b 74
RSP: 0018:ffffc90000007c50 EFLAGS: 00000003
RAX: ffffffff95d3aed8 RBX: 0000000000000002 RCX: 00000000fffffffe
RDX: 0000000000000000 RSI: ffff88806a9b2f80 RDI: ffff88806a9b2f80
RBP: ffff88806a9b2440 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88806a9b2f30
R13: ffff88806a9b2f80 R14: 0000000000000002 R15: 0000000000000001
FS: 00007f27f668a6c0(0000) GS:ffff888124754000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fec1b37fd38 CR3: 000000004cc3d000 CR4: 00000000003526f0
DR0: 0000000000000007 DR1: 0000000000000002 DR2: 0000000000000008
DR3: 1000000100000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire kernel/locking/lockdep.c:5871 [inline]
lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5828
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
advance_sched+0x699/0xc80 net/sched/sch_taprio.c:985
__run_hrtimer kernel/time/hrtimer.c:1761 [inline]
__hrtimer_run_queues+0x1ff/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+0x108/0x3f0 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:debug_lockdep_rcu_enabled+0x26/0x40 kernel/rcu/update.c:320
Code: 90 90 90 90 f3 0f 1e fa 8b 05 66 5b 28 05 85 c0 74 20 8b 05 60 8c 28 05 85 c0 74 16 65 48 8b 05 28 0e 4d 08 8b 80 ec 0a 00 00 <85> c0 0f 94 c0 0f b6 c0 c3 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00
RSP: 0018:ffffc9000c656d78 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffffc9000c657540 RCX: ffffc9000c658001
RDX: ffffc9000c657548 RSI: ffffc9000c657518 RDI: ffffc9000c656e00
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000011fdd R12: ffffc9000c656e40
R13: ffffc9000c656df0 R14: ffffc9000c657540 R15: ffffc9000c656e24
rcu_read_unlock include/linux/rcupdate.h:869 [inline]
class_rcu_destructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0x3de/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
save_stack+0x160/0x1f0 mm/page_owner.c:156
__set_page_owner+0x91/0x550 mm/page_owner.c:329
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1704
prep_new_page mm/page_alloc.c:1712 [inline]
get_page_from_freelist+0x1321/0x3890 mm/page_alloc.c:3669
__alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:4959
alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2419
folio_alloc_mpol_noprof+0x36/0x2f0 mm/mempolicy.c:2438
shmem_alloc_folio+0x135/0x160 mm/shmem.c:1851
shmem_alloc_and_add_folio+0x499/0xc20 mm/shmem.c:1890
shmem_get_folio_gfp+0x67f/0x1600 mm/shmem.c:2532
shmem_fault+0x1fe/0xa30 mm/shmem.c:2733
__do_fault+0x10a/0x490 mm/memory.c:5189
do_read_fault mm/memory.c:5610 [inline]
do_fault mm/memory.c:5744 [inline]
do_pte_missing mm/memory.c:4251 [inline]
handle_pte_fault mm/memory.c:6089 [inline]
__handle_mm_fault+0x3c2a/0x5490 mm/memory.c:6232
handle_mm_fault+0x589/0xd10 mm/memory.c:6401
faultin_page mm/gup.c:1186 [inline]
__get_user_pages+0x589/0x3b80 mm/gup.c:1488
populate_vma_page_range+0x278/0x3a0 mm/gup.c:1926
__mm_populate+0x1d8/0x380 mm/gup.c:2029
mm_populate include/linux/mm.h:3348 [inline]
vm_mmap_pgoff+0x362/0x450 mm/util.c:584
ksys_mmap_pgoff+0x7d/0x5c0 mm/mmap.c:607
__do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline]
__se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline]
__x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f27f578e929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f27f668a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f27f59b5fa0 RCX: 00007f27f578e929
RDX: b635773f06ebbee2 RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f27f5810b39 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f27f59b5fa0 R15: 00007fffbbda8138
rcu: rcu_preempt kthread starved for 10502 jiffies! g110217 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:27368 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x116a/0x5de0 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6878
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+0x5d4/0x6f0 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:
CPU: 1 UID: 0 PID: 1328 Comm: kworker/u8:7 Not tainted 6.16.0-rc1-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0xd7b/0x1510 kernel/smp.c:885
Code: e8 1a 17 0c 00 45 85 ed 74 46 48 8b 14 24 49 89 d6 49 89 d5 49 c1 ee 03 41 83 e5 07 4d 01 e6 41 83 c5 03 e8 b7 1b 0c 00 f3 90 <41> 0f b6 06 41 38 c5 7c 08 84 c0 0f 85 6f 05 00 00 8b 43 08 31 ff
RSP: 0018:ffffc90004a6f8a0 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b8443ba0 RCX: ffffffff81b0011d
RDX: ffff888029120000 RSI: ffffffff81b000f9 RDI: 0000000000000005
RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: dffffc0000000000
R13: 0000000000000003 R14: ffffed1017088775 R15: ffff8880b853cf40
FS: 0000000000000000(0000) GS:ffff888124854000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005649fd0bb008 CR3: 000000000e382000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1052
on_each_cpu include/linux/smp.h:71 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2660 [inline]
smp_text_poke_batch_finish+0x27b/0xdb0 arch/x86/kernel/alternative.c:2870
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
jump_label_update+0x376/0x550 kernel/jump_label.c:919
static_key_enable_cpuslocked+0x1b7/0x270 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
toggle_allocation_gate mm/kfence/core.c:850 [inline]
toggle_allocation_gate+0xfa/0x280 mm/kfence/core.c:842
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+0x5d4/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245