rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=df5c/1/0x4000000000000000 softirq=20318/20319 fqs=3
(detected by 1, t=10505 jiffies, g=27473, q=131 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 6573 Comm: syz.4.514 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:check_region_inline mm/kasan/generic.c:169 [inline]
RIP: 0010:kasan_check_range+0xd/0x290 mm/kasan/generic.c:189
Code: c3 0f 0b b8 ea ff ff ff c3 0f 0b b8 ea ff ff ff c3 00 00 cc cc 00 00 cc cc 00 00 cc cc b0 01 48 85 f6 0f 84 a4 01 00 00 41 57 <41> 56 53 49 89 f8 49 01 f0 0f 82 57 02 00 00 49 89 f8 49 c1 e8 2f
RSP: 0018:ffffc90000007890 EFLAGS: 00000002
RAX: 0000000000000001 RBX: ffff888076429dc0 RCX: ffffffff8163aab4
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90ae2248
RBP: 0000000000000008 R08: dffffc0000000000 R09: fffffbfff215c44a
R10: fffffbfff215c44a R11: 1ffffffff215c449 R12: 0000000000000100
R13: dffffc0000000000 R14: ffff88807642a918 R15: 000000000000005e
FS: 00007f9dc63cd6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c30ff87 CR3: 00000000743f8000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
instrument_atomic_read include/linux/instrumented.h:72 [inline]
_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
hlock_class kernel/locking/lockdep.c:228 [inline]
mark_lock+0x94/0x320 kernel/locking/lockdep.c:4606
mark_usage kernel/locking/lockdep.c:4549 [inline]
__lock_acquire+0xd6f/0x7c50 kernel/locking/lockdep.c:5003
lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
_raw_spin_lock_irq+0x9f/0xe0 kernel/locking/spinlock.c:170
__run_hrtimer kernel/time/hrtimer.c:1756 [inline]
__hrtimer_run_queues+0x63a/0xd60 kernel/time/hrtimer.c:1816
hrtimer_interrupt+0x3c5/0x9c0 kernel/time/hrtimer.c:1878
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
__sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:119 [inline]
RIP: 0010:lock_is_held_type+0x2e/0x190 kernel/locking/lockdep.c:5698
Code: 56 41 55 41 54 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 bd ff ff ff ff 83 3d ec 51 08 04 00 0f 84 03 01 00 00 <65> 8b 05 3b 24 eb 75 85 c0 0f 85 f4 00 00 00 65 48 8b 1d eb 19 eb
RSP: 0018:ffffc9000d95f790 EFLAGS: 00000202
RAX: 4f534ecd95c47800 RBX: dffffc0000000000 RCX: 4f534ecd95c47800
RDX: ffff888076429dc0 RSI: 00000000ffffffff RDI: ffffffff8cb2a9e0
RBP: 00000000ffffffff R08: dffffc0000000000 R09: fffff94000284c6f
R10: fffff94000284c6f R11: 1ffffd4000284c6e R12: 1ffff92001b2bf25
R13: ffffc9000d95f928 R14: 0000000000000000 R15: ffff8880184e9678
xa_entry include/linux/xarray.h:1198 [inline]
xas_next_entry+0x202/0x3d0 include/linux/xarray.h:1689
next_map_page mm/filemap.c:3426 [inline]
filemap_map_pages+0xda1/0x10d0 mm/filemap.c:3498
do_fault_around mm/memory.c:4600 [inline]
do_read_fault mm/memory.c:4626 [inline]
do_fault mm/memory.c:4760 [inline]
handle_pte_fault mm/memory.c:5031 [inline]
__handle_mm_fault mm/memory.c:5173 [inline]
handle_mm_fault+0x2889/0x3e70 mm/memory.c:5294
faultin_page mm/gup.c:1026 [inline]
__get_user_pages+0x3ff/0xeb0 mm/gup.c:1250
populate_vma_page_range+0x214/0x2b0 mm/gup.c:1607
__mm_populate+0x248/0x370 mm/gup.c:1721
mm_populate include/linux/mm.h:2837 [inline]
vm_mmap_pgoff+0x203/0x2b0 mm/util.c:525
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f9dc558ebe9
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:00007f9dc63cd038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f9dc57c5fa0 RCX: 00007f9dc558ebe9
RDX: 0000000000000003 RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f9dc5611e19 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9dc57c6038 R14: 00007f9dc57c5fa0 R15: 00007ffe00637918
rcu: rcu_preempt kthread starved for 10490 jiffies! g27473 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:27840 pid:16 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 4421 Comm: kworker/u4:11 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:424 [inline]
RIP: 0010:smp_call_function_many_cond+0xe7b/0x1270 kernel/smp.c:998
Code: 00 00 00 41 8b 1f 89 de 83 e6 01 31 ff e8 5d d9 0a 00 83 e3 01 48 bb 00 00 00 00 00 fc ff df 75 07 e8 e9 d5 0a 00 eb 37 f3 90 <41> 0f b6 04 1c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 ce d5 0a
RSP: 0018:ffffc9000488f800 EFLAGS: 00000293
RAX: ffffffff8175fa52 RBX: dffffc0000000000 RCX: ffff88801afbd940
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000488f960 R08: dffffc0000000000 R09: fffffbfff215c449
R10: fffffbfff215c449 R11: 1ffffffff215c448 R12: 1ffff110171c85ad
R13: ffff8880b8f3bb40 R14: 0000000000000000 R15: ffff8880b8e42d68
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd2738f56c0 CR3: 000000000c88e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1166
on_each_cpu include/linux/smp.h:71 [inline]
text_poke_sync arch/x86/kernel/alternative.c:1574 [inline]
text_poke_bp_batch+0x2b0/0x7d0 arch/x86/kernel/alternative.c:1774
text_poke_flush arch/x86/kernel/alternative.c:1965 [inline]
text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1972
arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
static_key_disable_cpuslocked+0xc1/0x1a0 kernel/jump_label.c:237
static_key_disable+0x16/0x20 kernel/jump_label.c:245
toggle_allocation_gate+0x38f/0x430 mm/kfence/core.c:819
process_one_work+0x898/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295