rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=8f7c/1/0x4000000000000000 softirq=88573/88583 fqs=0 rcu: (detected by 0, t=10502 jiffies, g=81653, q=1438 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 14029 Comm: rm Not tainted 6.14.0-rc6-syzkaller-00202-ga29967be967e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:87 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:104 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:129 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:161 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0x86/0x290 mm/kasan/generic.c:189 Code: 00 fc ff df 4f 8d 3c 31 4c 89 fd 4c 29 dd 48 83 fd 10 7f 29 48 85 ed 0f 84 3e 01 00 00 4c 89 cd 48 f7 d5 48 01 dd 41 80 3b 00 <0f> 85 c9 01 00 00 49 ff c3 48 ff c5 75 ee e9 1e 01 00 00 45 89 dc RSP: 0018:ffffc90000a28900 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 1ffffffff28a9909 RCX: ffffffff819ce8c5 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff9454c848 RBP: ffffffffffffffff R08: ffffffff9454c84f R09: 1ffffffff28a9909 R10: dffffc0000000000 R11: fffffbfff28a9909 R12: ffff88802d963c00 R13: ffff88802d963c00 R14: dffffc0000000001 R15: fffffbfff28a990a FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fda6a288108 CR3: 0000000061eba000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read include/linux/instrumented.h:68 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] hlock_class kernel/locking/lockdep.c:230 [inline] __lock_acquire+0xf55/0x2100 kernel/locking/lockdep.c:5224 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 debug_object_deactivate+0x158/0x390 lib/debugobjects.c:873 debug_hrtimer_deactivate kernel/time/hrtimer.c:460 [inline] debug_deactivate+0x1b/0x220 kernel/time/hrtimer.c:502 __run_hrtimer kernel/time/hrtimer.c:1769 [inline] __hrtimer_run_queues+0x305/0xd30 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:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5855 Code: 2b 00 74 08 4c 89 f7 e8 8a 50 8c 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc900048af2a0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000915e60 RCX: ffff88802d9646e8 RDX: dffffc0000000000 RSI: ffffffff8c2ac600 RDI: ffffffff8c810220 RBP: ffffc900048af3e8 R08: ffffffff9454c8f7 R09: 1ffffffff28a991e R10: dffffc0000000000 R11: fffffbfff28a991f R12: 1ffff92000915e5c R13: dffffc0000000000 R14: ffffc900048af300 R15: 0000000000000246 down_read+0xb1/0xa40 kernel/locking/rwsem.c:1524 anon_vma_lock_read include/linux/rmap.h:136 [inline] validate_mm+0x2c8/0x590 mm/vma.c:612 mmap_region+0x2193/0x2fa0 mm/vma.c:2545 do_mmap+0xecc/0x13a0 mm/mmap.c:561 vm_mmap_pgoff+0x214/0x430 mm/util.c:575 ksys_mmap_pgoff+0x4eb/0x720 mm/mmap.c:607 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: 0033:0x7fda6a2b0b74 Code: 63 08 44 89 e8 5b 41 5c 41 5d c3 41 89 ca 41 f7 c1 ff 0f 00 00 74 0c c7 05 f5 46 01 00 16 00 00 00 eb 17 b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 0c f7 d8 89 05 dc 46 01 00 48 83 c8 ff c3 0f RSP: 002b:00007fff50f7e788 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007fff50f7e7c8 RCX: 00007fda6a2b0b74 RDX: 0000000000000005 RSI: 0000000000123000 RDI: 00007fda6a041000 RBP: 00007fff50f7ef20 R08: 0000000000000003 R09: 0000000000028000 R10: 0000000000000812 R11: 0000000000000246 R12: 00007fda6a28d5c0 R13: 00007fff50f7efa8 R14: 0000000000027f38 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 10502 jiffies! g81653 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:26104 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0x190e/0x4c90 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: 0 UID: 0 PID: 13959 Comm: syz.3.1336 Not tainted 6.14.0-rc6-syzkaller-00202-ga29967be967e #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 c0 f4 0b 00 41 83 e4 01 4c 8b 64 24 68 75 07 e8 70 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:ffffc9000430f400 EFLAGS: 00000293 RAX: ffffffff81b5ef85 RBX: 1ffff110170e88f9 RCX: ffff88802733bc00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000430f600 R08: ffffffff81b5ef50 R09: 1ffffffff28a990e R10: dffffc0000000000 R11: fffffbfff28a990f R12: ffff8880b863fb48 R13: ffff8880b87447c8 R14: ffff8880b863fb40 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055558e2965c8 CR3: 0000000071428000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 000000000000000c DR2: 000000000000000e DR3: 00000000000000b4 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] tlb_flush_mmu+0x1aa/0x680 mm/mmu_gather.c:395 tlb_finish_mmu+0xd4/0x200 mm/mmu_gather.c:488 exit_mmap+0x52a/0xd40 mm/mmap.c:1297 __mmput+0x115/0x420 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: 0033:0x7f54b3d8d169 Code: Unable to access opcode bytes at 0x7f54b3d8d13f. RSP: 002b:00007f54b4bbc038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: 0000000000006000 RBX: 00007f54b3fa6080 RCX: 00007f54b3d8d169 RDX: 00000000fffffd2c RSI: 0000400000000000 RDI: 0000000000000005 RBP: 00007f54b3e0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f54b3fa6080 R15: 00007f54b40cfa28