rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=affc/1/0x4000000000000000 softirq=31788/31789 fqs=0
rcu: (detected by 1, t=10505 jiffies, g=32129, q=384 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 8979 Comm: syz.4.833 Not tainted 6.14.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:check_preemption_disabled+0x7/0x120 lib/smp_processor_id.c:13
Code: c6 60 1a 80 8c eb 1c 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 57 41 56 41 54 53 <48> 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 65 8b 1d 8c
RSP: 0018:ffffc90000007c28 EFLAGS: 00000082
RAX: 0000000000010000 RBX: ffffffff89fc9572 RCX: ffff888025548000
RDX: ffff888025548000 RSI: ffffffff8c801a60 RDI: ffffffff8c801a20
RBP: 0000000000000001 R08: ffffffff89fc9629 R09: 1ffff11003d7902b
R10: dffffc0000000000 R11: ffffed1003d7902c R12: dffffc0000000000
R13: ffff888035a1fc08 R14: ffff888035a1fc00 R15: ffff88801ebc8360
FS: 00007faf61bb16c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3aba1d CR3: 0000000024bc0000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:716
rcu_read_unlock include/linux/rcupdate.h:878 [inline]
advance_sched+0xac2/0xca0 net/sched/sch_taprio.c:987
__run_hrtimer kernel/time/hrtimer.c:1801 [inline]
__hrtimer_run_queues+0x59b/0xd30 kernel/time/hrtimer.c:1865
hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1927
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
__sysvec_apic_timer_interrupt+0x110/0x420 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
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xd8/0x140 kernel/locking/spinlock.c:194
Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 3e 2c 23 f6 f6 44 24 21 02 75 52 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 d3 1c 8c f5 65 8b 05 54 90 00 74 85 c0 74 43 48 c7 04 24 0e 36
RSP: 0018:ffffc90004627620 EFLAGS: 00000206
RAX: bd5bd836a6c55400 RBX: 1ffff920008c4ec8 RCX: ffffffff819d296a
RDX: dffffc0000000000 RSI: ffffffff8c2aa420 RDI: 0000000000000001
RBP: ffffc900046276b0 R08: ffffffff945118ff R09: 1ffffffff28a231f
R10: dffffc0000000000 R11: fffffbfff28a2320 R12: dffffc0000000000
R13: 1ffff920008c4ec4 R14: ffffc90004627640 R15: 0000000000000246
spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
__wake_up_common_lock+0x18c/0x1e0 kernel/sched/wait.c:108
__unix_dgram_recvmsg+0x61a/0x1320 net/unix/af_unix.c:2456
sock_recvmsg_nosec+0x18e/0x1d0 net/socket.c:1023
____sys_recvmsg+0x3cd/0x480 net/socket.c:2791
___sys_recvmsg net/socket.c:2835 [inline]
do_recvmmsg+0x426/0xab0 net/socket.c:2930
__sys_recvmmsg net/socket.c:3004 [inline]
__do_sys_recvmmsg net/socket.c:3027 [inline]
__se_sys_recvmmsg net/socket.c:3020 [inline]
__x64_sys_recvmmsg+0x199/0x250 net/socket.c:3020
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7faf60d8d169
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:00007faf61bb1038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007faf60fa6080 RCX: 00007faf60d8d169
RDX: 0000000000010106 RSI: 00004000000000c0 RDI: 0000000000000003
RBP: 00007faf60e0e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007faf60fa6080 R15: 00007ffc7669cda8
rcu: rcu_preempt kthread starved for 10505 jiffies! g32129 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:25784 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5378 [inline]
__schedule+0x18bc/0x4c40 kernel/sched/core.c:6765
__schedule_loop kernel/sched/core.c:6842 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6857
schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2024
rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2226
kthread+0x7a9/0x920 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 8939 Comm: syz.1.827 Not tainted 6.14.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0x1ba4/0x2d30 kernel/smp.c:885
Code: 03 84 c0 75 7e 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 30 f5 0b 00 41 83 e4 01 4c 8b 64 24 68 75 07 e8 e0 f0 0b 00 eb 41 f3 90 <48> b8 00 00 00 00 00 fc ff df 0f b6 04 03 84 c0 75 11 41 f7 45 00
RSP: 0018:ffffc9000af4ef40 EFLAGS: 00000293
RAX: ffffffff81b5cce5 RBX: 1ffff110170c8c75 RCX: ffff88802a8fda00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000af4f140 R08: ffffffff81b5ccb0 R09: 1ffff920015e9dd8
R10: dffffc0000000000 R11: fffff520015e9dd9 R12: ffff8880b873f9c8
R13: ffff8880b86463a8 R14: ffff8880b873f9c0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f78930d56c0 CR3: 000000007ac86000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
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:966 [inline]
flush_tlb_mm_range+0x42d/0x710 arch/x86/mm/tlb.c:1054
tlb_flush arch/x86/include/asm/tlb.h:20 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:481 [inline]
zap_pte_range mm/memory.c:1769 [inline]
zap_pmd_range mm/memory.c:1834 [inline]
zap_pud_range mm/memory.c:1863 [inline]
zap_p4d_range mm/memory.c:1884 [inline]
unmap_page_range+0x386a/0x4510 mm/memory.c:1905
unmap_vmas+0x3cc/0x5f0 mm/memory.c:1995
exit_mmap+0x283/0xd40 mm/mmap.c:1284
__mmput+0x115/0x410 kernel/fork.c:1356
exit_mm+0x220/0x310 kernel/exit.c:570
do_exit+0x9ad/0x28e0 kernel/exit.c:925
do_group_exit+0x207/0x2c0 kernel/exit.c:1087
get_signal+0x168c/0x1720 kernel/signal.c:3036
arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [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+0xce/0x340 kernel/entry/common.c:218
do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f76a258d169
Code: Unable to access opcode bytes at 0x7f76a258d13f.
RSP: 002b:00007f76a34950e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f76a27a5fa8 RCX: 00007f76a258d169
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f76a27a5fa8
RBP: 00007f76a27a5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f76a27a5fac
R13: 0000000000000000 R14: 00007ffc81e34f40 R15: 00007ffc81e35028