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charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: f777d1112ee5 Merge tag 'vfs-6.17-rc6.fixes' of git://git.k.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=11790d62580000 kernel config: https://syzkaller.appspot.com/x/.config?x=429771c55b615e85 dashboard link: https://syzkaller.appspot.com/bug?extid=e333f6ae9120efd3294a compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1439d562580000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14dac642580000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/860ff2f591a4/disk-f777d111.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/31f4ca3a76d4/vmlinux-f777d111.xz kernel image: https://storage.googleapis.com/syzbot-assets/c534fac91a74/bzImage-f777d111.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+e333f6ae9120efd3294a@syzkaller.appspotmail.com rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6880 rcu: (detected by 0, t=10502 jiffies, g=16217, q=2735 ncpus=2) task:syz.0.301 state:R running task stack:26952 pid:6880 tgid:6880 ppid:5958 task_flags:0x400040 flags:0x00004006 Call Trace: sched_show_task+0x49d/0x630 kernel/sched/core.c:7933 rcu_print_detail_task_stall_rnp kernel/rcu/tree_stall.h:292 [inline] print_other_cpu_stall+0xf78/0x1340 kernel/rcu/tree_stall.h:681 check_cpu_stall kernel/rcu/tree_stall.h:857 [inline] rcu_pending kernel/rcu/tree.c:3671 [inline] rcu_sched_clock_irq+0xa47/0x11b0 kernel/rcu/tree.c:2706 update_process_times+0x235/0x2d0 kernel/time/timer.c:2473 tick_sched_handle kernel/time/tick-sched.c:276 [inline] tick_nohz_handler+0x39a/0x520 kernel/time/tick-sched.c:297 __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x503/0xd40 kernel/time/hrtimer.c:1825 hrtimer_interrupt+0x45d/0xa90 kernel/time/hrtimer.c:1887 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline] __sysvec_apic_timer_interrupt+0x10b/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 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110 kernel/locking/spinlock.c:194 Code: 74 05 e8 8b d3 cb f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 b3 8b 95 f6 65 8b 05 dc dc fb 06 85 c0 74 40 48 c7 04 24 0e 36 RSP: 0018:ffffc90003aafb40 EFLAGS: 00000206 RAX: c013c10a5e9bae00 RBX: 0000000000000a02 RCX: c013c10a5e9bae00 RDX: 0000000000000006 RSI: ffffffff8d03a0c9 RDI: 0000000000000001 RBP: ffffc90003aafbd0 R08: ffffffff8f1d5a37 R09: 1ffffffff1e3ab46 R10: dffffc0000000000 R11: fffffbfff1e3ab47 R12: dffffc0000000000 R13: ffffffff8e16a380 R14: ffffffff8e16a380 R15: 1ffff92000755f68 unlock_rt_mutex_safe kernel/locking/rtmutex.c:344 [inline] rt_mutex_slowunlock+0x493/0x8a0 kernel/locking/rtmutex.c:1454 spin_unlock_irqrestore include/linux/spinlock_rt.h:122 [inline] vga_put drivers/pci/vgaarb.c:553 [inline] vga_arb_release+0x3fb/0xa90 drivers/pci/vgaarb.c:1455 __fput+0x45b/0xa80 fs/file_table.c:468 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f40e894ebe9 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:00007ffdfc93c728 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 000000000002310c RCX: 00007f40e894ebe9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f40e8b87da0 R08: 0000000000000001 R09: 00000004fc93ca1f R10: 0000001b30520000 R11: 0000000000000246 R12: 00007f40e8b8609c R13: 00007f40e8b86090 R14: ffffffffffffffff R15: 00007ffdfc93c840 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup