rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=7964/1/0x4000000000000000 softirq=47517/47521 fqs=3 rcu: (detected by 1, t=10502 jiffies, g=36425, q=292 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 11984 Comm: syz-executor Not tainted 6.15.0-rc3-syzkaller-00019-gbc3372351d0c #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:check_preemption_disabled+0x0/0xe0 lib/smp_processor_id.c:13 Code: c0 75 0f 65 8b 05 cc 5e 34 08 85 c0 74 04 90 0f 0b 90 e9 53 fc ff ff 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <41> 54 55 53 48 83 ec 08 65 8b 1d 85 24 34 08 65 8b 05 7a 24 34 08 RSP: 0018:ffffc90000007d48 EFLAGS: 00000046 RAX: 0000000000000001 RBX: ffff88803267d410 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff8dbca29f RDI: ffffffff8bf465c0 RBP: ffff88805af4c300 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88803267c880 R13: 0000000000000001 R14: 00000000ffffffff R15: 0000000000000004 FS: 0000555575797500(0000) GS:ffff8881249b2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fca0af17b30 CR3: 000000005d888000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:472 [inline] lock_is_held_type+0xdf/0x150 kernel/locking/lockdep.c:5939 lock_is_held include/linux/lockdep.h:249 [inline] advance_sched+0x7b1/0xc80 net/sched/sch_taprio.c:927 __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x1ff/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+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:qlink_free mm/kasan/quarantine.c:146 [inline] RIP: 0010:qlist_free_all+0x29/0x120 mm/kasan/quarantine.c:179 Code: 90 41 57 41 56 41 55 41 54 55 53 48 8b 2f 48 85 ed 0f 84 c9 00 00 00 49 89 fe 49 89 f5 eb 38 48 63 83 c0 00 00 00 4c 8b 65 00 <48> 89 df 48 29 c5 48 89 ee e8 79 eb ff ff 49 89 c7 66 90 48 89 ee RSP: 0018:ffffc9000c617a10 EFLAGS: 00000246 RAX: 0000000000000108 RBX: ffff8881432fe3c0 RCX: ffffea0000000000 RDX: 0000000000000000 RSI: ffffffff816b84a6 RDI: 0000000000000007 RBP: ffff888079658248 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff888066f2ef80 R13: 0000000000000000 R14: ffffc9000c617a48 R15: ffff888066f2ef40 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4161 [inline] slab_alloc_node mm/slub.c:4210 [inline] __do_kmalloc_node mm/slub.c:4340 [inline] __kmalloc_noprof+0x1d4/0x510 mm/slub.c:4353 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] tomoyo_encode2+0x100/0x3e0 security/tomoyo/realpath.c:45 tomoyo_encode+0x29/0x50 security/tomoyo/realpath.c:80 tomoyo_path_perm+0x3a5/0x460 security/tomoyo/file.c:831 tomoyo_path_symlink+0x97/0xe0 security/tomoyo/tomoyo.c:212 security_path_symlink+0x152/0x2e0 security/security.c:1984 do_symlinkat+0x10d/0x310 fs/namei.c:4747 __do_sys_symlinkat fs/namei.c:4765 [inline] __se_sys_symlinkat fs/namei.c:4762 [inline] __x64_sys_symlinkat+0x93/0xc0 fs/namei.c:4762 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: 0033:0x7fca0af8d6e7 Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0a 01 00 00 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:00007fff8898cdd8 EFLAGS: 00000202 ORIG_RAX: 000000000000010a RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fca0af8d6e7 RDX: 00007fca0b0122bd RSI: 00000000ffffff9c RDI: 00007fca0b010e2b RBP: 00007fff8898ce1c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000215 R13: 00000000000927c0 R14: 000000000003500f R15: 00007fff8898ce70 rcu: rcu_preempt kthread starved for 10496 jiffies! g36425 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:27704 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 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 8230 Comm: syz-executor Not tainted 6.15.0-rc3-syzkaller-00019-gbc3372351d0c #0 PREEMPT(full) 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+0x4a5/0x1290 kernel/smp.c:885 Code: 89 ee e8 be 12 0c 00 85 ed 74 48 48 8b 44 24 20 49 89 c4 83 e0 07 49 c1 ec 03 48 89 c5 4d 01 f4 83 c5 03 e8 5d 17 0c 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 de 0b 00 00 8b 43 08 31 RSP: 0018:ffffc9000c20f8b8 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b8441720 RCX: ffffffff81af38b9 RDX: ffff88807dd70000 RSI: ffffffff81af3893 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffed10170882e5 R13: 0000000000000001 R14: dffffc0000000000 R15: ffff8880b853b040 FS: 000055555df78500(0000) GS:ffff888124ab2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3dff8e56c0 CR3: 000000005142c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1052 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline] flush_tlb_multi arch/x86/mm/tlb.c:1275 [inline] flush_tlb_mm_range+0x322/0x1780 arch/x86/mm/tlb.c:1365 dup_mmap kernel/fork.c:765 [inline] dup_mm kernel/fork.c:1734 [inline] copy_mm kernel/fork.c:1786 [inline] copy_process+0x7961/0x91a0 kernel/fork.c:2429 kernel_clone+0xfc/0x960 kernel/fork.c:2844 __do_sys_clone+0xce/0x120 kernel/fork.c:2987 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: 0033:0x7f3dfeb849d3 Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00 RSP: 002b:00007ffe215b7448 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3dfeb849d3 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 000055555df787d0 R11: 0000000000000246 R12: 0000000000000000 R13: 00000000000927c0 R14: 000000000003506c R15: 00007ffe215b75e0