rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (0 ticks this GP) idle=e7fc/1/0x4000000000000000 softirq=51175/51175 fqs=0
rcu: (detected by 0, t=10506 jiffies, g=76769, q=19 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 11786 Comm: syz.5.1639 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline]
RIP: 0010:rcu_is_watching+0x3a/0xb0 kernel/rcu/tree.c:700
Code: e8 8b 99 15 09 89 c3 83 f8 08 73 60 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd 30 7a a7 8c 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 <74> 08 4c 89 f7 e8 0c 74 6e 00 48 c7 c3 28 6b 03 00 49 03 1e 48 89
RSP: 0018:ffffc900001f0b20 EFLAGS: 00000046
RAX: 1ffffffff194ef47 RBX: 0000000000000001 RCX: e2eaf4daaa227700
RDX: 0000000000000000 RSI: ffffffff8b1c8f80 RDI: ffffffff8b1c8f40
RBP: ffffc900001f0c60 R08: ffffffff8e8b19af R09: 1ffffffff1d16335
R10: dffffc0000000000 R11: fffffbfff1d16336 R12: ffffffff88ae05d9
R13: dffffc0000000000 R14: ffffffff8ca77a38 R15: dffffc0000000000
FS: 00007faa49bf66c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000001a000 CR3: 00000000273c1000 CR4: 00000000003506e0
DR0: 0000000000000008 DR1: 0000000000000007 DR2: 0000000000000004
DR3: 0000000000000008 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
trace_lock_release include/trace/events/lock.h:69 [inline]
lock_release+0xb5/0x8c0 kernel/locking/lockdep.c:5765
rcu_lock_release include/linux/rcupdate.h:344 [inline]
rcu_read_unlock include/linux/rcupdate.h:819 [inline]
advance_sched+0xb29/0xc80 net/sched/sch_taprio.c:1003
__run_hrtimer kernel/time/hrtimer.c:1750 [inline]
__hrtimer_run_queues+0x520/0xc40 kernel/time/hrtimer.c:1814
hrtimer_interrupt+0x3c9/0x9c0 kernel/time/hrtimer.c:1876
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline]
__sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline]
RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline]
RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:147 [inline]
RIP: 0010:wrmsrl arch/x86/include/asm/msr.h:262 [inline]
RIP: 0010:native_x2apic_icr_write arch/x86/include/asm/apic.h:217 [inline]
RIP: 0010:__x2apic_send_IPI_dest arch/x86/kernel/apic/x2apic_phys.c:113 [inline]
RIP: 0010:x2apic_send_IPI+0x74/0xd0 arch/x86/kernel/apic/x2apic_phys.c:50
Code: f0 48 c1 e8 03 42 0f b6 04 20 84 c0 75 3b 41 0f b7 16 0f ae f0 0f ae e8 83 fb 02 b8 00 04 00 00 0f 45 c3 b9 30 08 00 00 0f 30 <66> 90 5b 41 5c 41 5e 41 5f 5d c3 89 fe 89 fd 48 c7 c7 80 ac f9 8c
RSP: 0018:ffffc9001a0b7950 EFLAGS: 00000206
RAX: 00000000000000fb RBX: 00000000000000fb RCX: 0000000000000830
RDX: 0000000000000000 RSI: 00000000000000fb RDI: 0000000000000000
RBP: ffffc9001a0b7a58 R08: ffffffff8e8b19af R09: 1ffffffff1d16335
R10: dffffc0000000000 R11: fffffbfff1d16336 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffff8880b8e219d0 R15: ffffffff8ca77a30
generic_exec_single+0x216/0x4f0 kernel/smp.c:415
smp_call_function_single_async+0x75/0x100 kernel/smp.c:695
rdmsr_safe_on_cpu+0x166/0x2a0 arch/x86/lib/msr-smp.c:181
msr_read+0x154/0x250 arch/x86/kernel/msr.c:66
vfs_read+0x28b/0x970 fs/read_write.c:468
ksys_read+0x150/0x260 fs/read_write.c:613
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7faa4b99ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007faa49bf6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007faa4bc15fa0 RCX: 00007faa4b99ce59
RDX: 0000000000018ff8 RSI: 0000200000019680 RDI: 0000000000000005
RBP: 00007faa4ba32d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007faa4bc16038 R14: 00007faa4bc15fa0 R15: 00007ffca983ec28
rcu: rcu_preempt kthread starved for 10506 jiffies! g76769 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
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:26920 pid:17 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x1553/0x45a0 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168
rcu_gp_fqs_loop+0x313/0x1590 kernel/rcu/tree.c:1667
rcu_gp_kthread+0x9d/0x3b0 kernel/rcu/tree.c:1866
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 11785 Comm: syz.5.1639 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline]
RIP: 0010:smp_call_function_many_cond+0xdfe/0x1140 kernel/smp.c:855
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 cb f5 0a 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 06 f2 0a 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 ea f1
RSP: 0000:ffffc900030f7820 EFLAGS: 00000293
RAX: ffffffff817c3166 RBX: 1ffff110171e826d RCX: ffff88802bf9bc00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900030f79a0 R08: ffffffff911c6507 R09: 1ffffffff2238ca0
R10: dffffc0000000000 R11: fffffbfff2238ca1 R12: ffff8880b8f41368
R13: dffffc0000000000 R14: ffff8880b8e3d148 R15: 0000000000000001
FS: 000055558e015500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007faa4a3f7988 CR3: 00000000273c1000 CR4: 00000000003506f0
DR0: 0000000000000008 DR1: 0000000000000007 DR2: 0000000000000004
DR3: 0000000000000008 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1022
__flush_tlb_multi arch/x86/include/asm/paravirt.h:87 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:990 [inline]
flush_tlb_mm_range+0x424/0x6a0 arch/x86/mm/tlb.c:1078
flush_tlb_page arch/x86/include/asm/tlbflush.h:255 [inline]
ptep_clear_flush+0x120/0x170 mm/pgtable-generic.c:101
wp_page_copy mm/memory.c:3162 [inline]
do_wp_page+0x1dc3/0x35f0 mm/memory.c:3469
handle_pte_fault mm/memory.c:5063 [inline]
__handle_mm_fault mm/memory.c:5188 [inline]
handle_mm_fault+0x135d/0x4c00 mm/memory.c:5353
do_user_addr_fault+0xac8/0x12c0 arch/x86/mm/fault.c:1322
handle_page_fault arch/x86/mm/fault.c:1463 [inline]
exc_page_fault+0x64/0x100 arch/x86/mm/fault.c:1516
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7faa4b9bc16e
Code: 48 89 c2 48 83 ca 01 48 89 15 d6 13 d9 00 48 8b 15 e7 13 d9 00 48 8d 35 e0 13 d9 00 48 89 b3 c8 02 00 00 48 89 93 c0 02 00 00 <48> 89 42 08 48 89 05 c7 13 d9 00 48 8b 3d 18 2c 23 00 48 8b 05 a9
RSP: 002b:00007ffca983ebc0 EFLAGS: 00010206
RAX: 00007faa49bb4980 RBX: 00007faa49bb46c0 RCX: 00007faa49bd5980
RDX: 00007faa4a3f7980 RSI: 00007faa4c74d540 RDI: 00007faa49bb46c0
RBP: 000000000000000b R08: 00007faa49bb46c0 R09: 00007ffca983ec27
R10: 0000000000000008 R11: 0000000000000246 R12: 000000000000000b
R13: 00007faa49b94000 R14: 00007faa49bb46c0 R15: 00007ffca983ec28