rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=522c/1/0x4000000000000000 softirq=119439/119459 fqs=19
rcu: (detected by 1, t=10502 jiffies, g=109193, q=828 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 22082 Comm: syz.1.7036 Not tainted 6.15.0-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:rb_next+0x0/0xe0 lib/rbtree.c:493
Code: 48 c1 e8 03 42 80 3c 38 00 74 e3 4c 89 f7 e8 17 8b d4 f6 eb d9 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 41 57 41 56 53 48 89 fb 49 bf 00 00 00 00 00 fc ff df
RSP: 0018:ffffc90000007d00 EFLAGS: 00000006
RAX: ffffffff8b4bb022 RBX: ffff8880b8827910 RCX: ffff888056125a00
RDX: 0000000000010000 RSI: ffff88801df38340 RDI: ffff88801df38340
RBP: 1ffff11003be7068 R08: ffffffff8f7e0b77 R09: 1ffffffff1efc16e
R10: dffffc0000000000 R11: fffffbfff1efc16f R12: ffff8880b8827918
R13: dffffc0000000000 R14: ffff88801df38340 R15: 1ffff11017104f23
FS: 000055556b708500(0000) GS:ffff8881260f6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f61eff8 CR3: 0000000064f90000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
rb_erase_cached include/linux/rbtree.h:124 [inline]
timerqueue_del+0x8a/0x100 lib/timerqueue.c:57
__remove_hrtimer kernel/time/hrtimer.c:1121 [inline]
__run_hrtimer kernel/time/hrtimer.c:1741 [inline]
__hrtimer_run_queues+0x364/0xc60 kernel/time/hrtimer.c:1825
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
__sysvec_apic_timer_interrupt+0x108/0x410 arch/x86/kernel/apic/apic.c:1055
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5870
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 6b 60 d4 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:ffffc900039ffbd8 EFLAGS: 00000206
RAX: 51e1853cf8da5100 RBX: 0000000000000000 RCX: 51e1853cf8da5100
RDX: 0000000000000001 RSI: ffffffff8d92487d RDI: ffffffff8bc12240
RBP: ffffffff81734e8c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff81734e8c R12: 0000000000000002
R13: ffffffff8df3dfa0 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock_sched include/linux/rcupdate.h:932 [inline]
pfn_valid include/linux/mmzone.h:2117 [inline]
__virt_addr_valid+0x1a9/0x540 arch/x86/mm/physaddr.c:65
kasan_addr_to_slab+0xd/0x90 mm/kasan/common.c:37
kasan_record_aux_stack+0xf/0xd0 mm/kasan/generic.c:533
kvfree_call_rcu+0xbb/0x410 mm/slab_common.c:1962
timerfd_release+0x1be/0x240 fs/timerfd.c:242
__fput+0x44c/0xa70 fs/file_table.c:465
task_work_run+0x1d4/0x260 kernel/task_work.c:227
resume_user_mode_work+0x5e/0x80 include/linux/resume_user_mode.h:50
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x9a/0x120 kernel/entry/common.c:218
do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fec0278e969
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:00007ffc87e57918 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000009557d RCX: 00007fec0278e969
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fec029b7ba0 R08: 0000000000000001 R09: 0000000587e57c0f
R10: 00007fec02600000 R11: 0000000000000246 R12: 00007fec029b5fac
R13: 00007fec029b5fa0 R14: ffffffffffffffff R15: 00007ffc87e57a30
</TASK>
rcu: rcu_preempt kthread starved for 10405 jiffies! g109193 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:27304 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x168f/0x4c70 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6860
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2046
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2248
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 22064 Comm: syz.7.7033 Not tainted 6.15.0-syzkaller #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+0xe69/0x11c0 kernel/smp.c:885
Code: 00 45 8b 2f 44 89 ee 83 e6 01 31 ff e8 70 6d 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 1b 69 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 00 69 0b
RSP: 0018:ffffc9000b36f380 EFLAGS: 00000293
RAX: ffffffff81b487e0 RBX: ffff8880b893abc0 RCX: ffff88801a180000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000b36f4e0 R08: ffffc9000b36f307 R09: 1ffff9200166de60
R10: dffffc0000000000 R11: fffff5200166de61 R12: 1ffff11017108221
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b8841108
FS: 0000000000000000(0000) GS:ffff8881261f6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d616ff8 CR3: 000000001c3fa000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
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:1291 [inline]
flush_tlb_mm_range+0x6ae/0x12b0 arch/x86/mm/tlb.c:1381
tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:480 [inline]
zap_pte_range mm/memory.c:1758 [inline]
zap_pmd_range mm/memory.c:1823 [inline]
zap_pud_range mm/memory.c:1852 [inline]
zap_p4d_range mm/memory.c:1873 [inline]
unmap_page_range+0x35d6/0x4210 mm/memory.c:1894
unmap_vmas+0x25d/0x3c0 mm/memory.c:1984
exit_mmap+0x245/0xba0 mm/mmap.c:1284
__mmput+0x118/0x410 kernel/fork.c:1380
exit_mm+0x1da/0x2c0 kernel/exit.c:589
do_exit+0x859/0x2550 kernel/exit.c:940
do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
__do_sys_exit_group kernel/exit.c:1113 [inline]
__se_sys_exit_group kernel/exit.c:1111 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1111
x64_sys_call+0x21ba/0x21c0 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc6c298e969
Code: Unable to access opcode bytes at 0x7fc6c298e93f.
RSP: 002b:00007ffe507c31e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fc6c298e969
RDX: 00007fc6c17f9000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffe507c324c R08: 00000005507c32df R09: 00000000000927c0
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000077
R13: 00000000000927c0 R14: 000000000009532e R15: 00007ffe507c32a0
</TASK>