rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (7 ticks this GP) idle=ba4c/1/0x4000000000000000 softirq=21158/21158 fqs=0
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6777/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=11877, q=384 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6786 Comm: syz.3.219 Not tainted 6.15.0-rc5-syzkaller-00032-g0d8d44db295c #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:3799 [inline]
RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3822 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3877 [inline]
RIP: 0010:__lock_acquire+0xaba/0x1ba0 kernel/locking/lockdep.c:5235
Code: 00 00 00 e9 82 fa ff ff 48 89 df 48 89 14 24 e8 3c a8 ff ff 4c 8b 04 24 48 b8 eb 83 b5 80 46 86 c8 61 49 0f af c0 48 c1 e8 2d <48> 8d 0c c5 00 40 e8 96 48 89 04 24 48 8b 04 c5 00 40 e8 96 48 89
RSP: 0018:ffffc90000a08a20 EFLAGS: 00000006
RAX: 00000000000171dd RBX: ffff88807cebd398 RCX: 000000004760b322
RDX: 07b24d8723fa41a2 RSI: 000000009ab1ca54 RDI: ffff88807cebd398
RBP: ffff88807cebd370 R08: 07b24d8723fa41a2 R09: 0000000000000001
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000002 R14: ffff88807cebc880 R15: 0000000000000000
FS: 00007f03cd7d56c0(0000) GS:ffff888124adf000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000020000 CR3: 0000000037403000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire kernel/locking/lockdep.c:5866 [inline]
lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5823
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
debug_object_activate+0x14c/0x4c0 lib/debugobjects.c:818
debug_hrtimer_activate kernel/time/hrtimer.c:445 [inline]
debug_activate kernel/time/hrtimer.c:484 [inline]
enqueue_hrtimer+0x23/0x3b0 kernel/time/hrtimer.c:1088
__run_hrtimer kernel/time/hrtimer.c:1778 [inline]
__hrtimer_run_queues+0x8ff/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:1038 [inline]
__sysvec_apic_timer_interrupt+0x108/0x3f0 arch/x86/kernel/apic/apic.c:1055
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1049
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:handle_softirqs+0x1dd/0x8e0 kernel/softirq.c:565
Code: 88 6c 24 26 4c 89 7c 24 18 48 c7 c7 a0 83 8b 8b e8 48 23 f0 09 65 66 c7 05 b6 56 27 12 00 00 e8 39 3d 46 00 fb bb ff ff ff ff <49> c7 c7 c0 c0 00 8e 41 0f bc dc 83 c3 01 0f 85 a4 00 00 00 e9 b1
RSP: 0018:ffffc90000a08f28 EFLAGS: 00000206
RAX: 0000000000005a28 RBX: 00000000ffffffff RCX: ffffffff81c2f5bf
RDX: 0000000000000000 RSI: ffffffff8dbe123f RDI: ffffffff8bf482a0
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff90850417 R11: 0000000000000000 R12: 0000000000000386
R13: 000000000000000a R14: 1ffff920001411ed R15: ffffed100f9d7910
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0x109/0x170 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1049
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:rdmsr_safe_on_cpu+0xb2/0x210 arch/x86/lib/msr-smp.c:175
Code: de b7 fc 31 c0 b9 0f 00 00 00 31 f6 4c 8d 44 24 60 ba 78 00 00 00 48 c7 44 24 20 00 00 00 00 4c 89 c7 4c 89 44 24 38 f3 48 ab <4c> 89 c7 48 c7 44 24 28 00 00 00 00 48 c7 44 24 30 30 52 03 85 e8
RSP: 0018:ffffc90003e7fb20 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 1ffff920007cff64 RCX: 0000000000000000
RDX: 0000000000000078 RSI: 0000000000000000 RDI: ffffc90003e7fbf8
RBP: ffffc90003e7fc68 R08: ffffc90003e7fb80 R09: 0000000000000000
R10: 0000000000011a68 R11: 0000000000000000 R12: ffffc90003e7fcb4
R13: ffffc90003e7fcb0 R14: 0000000000000000 R15: 0000000000000000
msr_read+0x19d/0x250 arch/x86/kernel/msr.c:66
vfs_read+0x1de/0xc70 fs/read_write.c:568
ksys_read+0x12a/0x240 fs/read_write.c:713
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f03cf98e969
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:00007f03cd7d5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f03cfbb6160 RCX: 00007f03cf98e969
RDX: 0000000000018ff8 RSI: 0000200000019680 RDI: 000000000000000c
RBP: 00007f03cfa10ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f03cfbb6160 R15: 00007ffc669e9d48
task:syz.0.217 state:R running task stack:26872 pid:6777 tgid:6775 ppid:5808 task_flags:0x40044c flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x116f/0x5de0 kernel/sched/core.c:6767
preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6947
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
zap_pte_range mm/memory.c:1761 [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+0xf08/0x4390 mm/memory.c:1894
unmap_single_vma+0x194/0x2a0 mm/memory.c:1940
unmap_vmas+0x22c/0x490 mm/memory.c:1984
exit_mmap+0x1b9/0xb90 mm/mmap.c:1284
__mmput+0x12a/0x410 kernel/fork.c:1379
mmput+0x62/0x70 kernel/fork.c:1401
exit_mm kernel/exit.c:589 [inline]
do_exit+0x9d1/0x2c30 kernel/exit.c:940
do_group_exit+0xd3/0x2a0 kernel/exit.c:1102
get_signal+0x2673/0x26d0 kernel/signal.c:3034
arch_do_signal_or_restart+0x8f/0x7d0 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+0x150/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x260 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f54e038e56b
RSP: 002b:00007f54e1227f10 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: fffffffffffffffc RBX: 0000000000000003 RCX: 00007f54e038e56b
RDX: 00007f54e1228fe0 RSI: 0000000080085502 RDI: 0000000000000003
RBP: 00007f54e1228fe0 R08: 0000000000000080 R09: 00007f54e1227fd8
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000080085502
R13: 0000000800000000 R14: 0000000000000012 R15: 00007f54e041ba1e
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g11877 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=1 timer-softirq=10176
rcu: rcu_preempt kthread starved for 10502 jiffies! g11877 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:28856 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x116f/0x5de0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6860
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2046
rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2248
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245