rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=dc84/1/0x4000000000000000 softirq=26529/26542 fqs=3
rcu: 	(detected by 0, t=10502 jiffies, g=17397, q=1826 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6700 Comm: modprobe Not tainted 6.16.0-syzkaller-12111-gd7e82594a45c #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:__kasan_check_read+0xa/0x20 mm/kasan/shadow.c:31
Code: 31 ed eb cf cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 89 f6 48 8b 0c 24 <31> d2 e9 ef e4 ff ff 66 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc90000a08d00 EFLAGS: 00000046
RAX: ffffffff81ade29e RBX: ffff888020bb1340 RCX: ffffffff81ade2b7
RDX: 0000000000010000 RSI: 0000000000000008 RDI: ffffffff8fa34630
RBP: 0000000000000000 R08: ffffffff99d8e3bb R09: 1ffffffff33b1c77
R10: dffffc0000000000 R11: fffffbfff33b1c78 R12: dffffc0000000000
R13: 0000000000000001 R14: ffff8880b8727b80 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888125d21000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5520449e9c CR3: 000000000df36000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 cpumask_test_cpu include/linux/cpumask.h:646 [inline]
 cpu_online include/linux/cpumask.h:1205 [inline]
 trace_hrtimer_start include/trace/events/timer.h:222 [inline]
 debug_activate kernel/time/hrtimer.c:485 [inline]
 enqueue_hrtimer+0x77/0x3a0 kernel/time/hrtimer.c:1088
 __run_hrtimer kernel/time/hrtimer.c:1778 [inline]
 __hrtimer_run_queues+0x656/0xc60 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
 __sysvec_apic_timer_interrupt+0x108/0x410 arch/x86/kernel/apic/apic.c:1056
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:kasan_record_aux_stack+0xae/0xd0 mm/kasan/generic.c:547
Code: 0f af c7 48 01 c6 48 39 f3 77 03 48 89 de 4c 89 f7 e8 36 02 f5 ff 49 63 8e bc 00 00 00 48 85 c9 74 1a 48 01 c8 74 15 8b 48 08 <89> 48 0c 31 ff 31 f6 48 89 c3 e8 83 ce ff ff 89 43 08 5b 41 5e c3
RSP: 0018:ffffc900041af9d8 EFLAGS: 00000282
RAX: ffff888032d26880 RBX: ffff888032d26780 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff888032d26780 RDI: ffff88801bad5b40
RBP: 000000000021a310 R08: 0000000000000000 R09: ffffffff81748958
R10: 000000000000000d R11: ffffffff81ac3890 R12: ffffea0000cb4980
R13: 0000000000000000 R14: ffff88801bad5b40 R15: ffffffff820de0df
 slab_free_hook mm/slub.c:2378 [inline]
 slab_free mm/slub.c:4680 [inline]
 kmem_cache_free+0x2f6/0x400 mm/slub.c:4782
 exit_mmap+0x53f/0xb50 mm/mmap.c:1305
 __mmput+0x118/0x430 kernel/fork.c:1129
 exit_mm+0x1da/0x2c0 kernel/exit.c:582
 do_exit+0x648/0x2300 kernel/exit.c:949
 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+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1cafb226c5
Code: Unable to access opcode bytes at 0x7f1cafb2269b.
RSP: 002b:00007ffc4b981348 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f1cafc23fe8 RCX: 00007f1cafb226c5
RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000001
RBP: 0000000000000001 R08: 00007ffc4b9812d8 R09: 0000000000000000
R10: 00007ffc4b981170 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f1cafc22680 R15: 00007f1cafc24000
 </TASK>
rcu: rcu_preempt kthread starved for 10485 jiffies! g17397 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:27224 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7058
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
 kthread+0x70e/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 101 PID: 5530 Comm: dhcpcd Not tainted 6.16.0-syzkaller-12111-gd7e82594a45c #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xd33/0x12d0 kernel/smp.c:877
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 b6 62 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 61 5e 0b 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 45 5e
RSP: 0018:ffffc90003aaf560 EFLAGS: 00000293
RAX: ffffffff81b44d6b RBX: 1ffff110170e7f61 RCX: ffff88802de10000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003aaf6e0 R08: ffffffff8fa34637 R09: 1ffffffff1f468c6
R10: dffffc0000000000 R11: fffffbfff1f468c7 R12: ffff8880b873fb08
R13: dffffc0000000000 R14: ffff8880b863b1c0 R15: 0000000000000001
FS:  00007f0edee42740(0000) GS:ffff888125c21000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055e05c3f5138 CR3: 0000000023f8c000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1044
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
 flush_tlb_mm_range+0x6b1/0x12d0 arch/x86/mm/tlb.c:1451
 tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
 tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:490 [inline]
 tlb_flush_mmu+0x1a7/0x680 mm/mmu_gather.c:403
 tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497
 vms_clear_ptes+0x42c/0x540 mm/vma.c:1235
 vms_complete_munmap_vmas+0x206/0x8a0 mm/vma.c:1277
 do_vmi_align_munmap+0x358/0x420 mm/vma.c:1536
 __do_sys_brk mm/mmap.c:173 [inline]
 __se_sys_brk+0x74e/0xb90 mm/mmap.c:115
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0edef3b6c7
Code: 4d 85 ed 74 e0 4d 85 e4 74 0b 48 89 ef 41 ff d4 4c 89 ee eb da 48 89 f7 e8 e6 1c f3 ff eb f1 0f 1f 40 00 b8 0c 00 00 00 0f 05 <48> 8b 15 6a a7 0d 00 48 89 02 48 39 f8 72 0a 31 c0 c3 0f 1f 80 00
RSP: 002b:00007ffc5128d4e8 EFLAGS: 00000206 ORIG_RAX: 000000000000000c
RAX: ffffffffffffffda RBX: fffffffffffef000 RCX: 00007f0edef3b6c7
RDX: fffffffffffff000 RSI: 0000000000000040 RDI: 0000556b6d148000
RBP: 0000556b6d159000 R08: 0000000000020950 R09: 0000000000000000
R10: 0000000000000040 R11: 0000000000000206 R12: 00007f0edf01de50
R13: 0000000000000000 R14: 0000000000001081 R15: 00007f0edf016ac0
 </TASK>