[BUG] Possible deadlock in __perf_event_task_sched_out

[Tianyu Li]

Hi,

I'm hitting a possible deadlock in __perf_event_task_sched_out. It's first detected via a fuzzing framework on Linux 6.18.0-rc6, and it also appears to be reproducible on v6.18. Since the report itself is already quite clear, I don’t want to risk adding inaccurate analysis here. Instead, I have attached the relevant information and materials below for your review.

    Kernel source: https://cdn.kernel.org/pub/linux/kernel/v6.x/linux-6.18.tar.xz
    Kernel configuration: https://github.com/j1akai/KConfigFuzz_bug/raw/refs/heads/main/x86/mainline-config
    Kernel log(fuzz report): https://github.com/Wxm-233/KConfigFuzz_crashes/raw/refs/heads/main/8facfbb5acbe6b82e7b5bf8d27be8930172c96c1/repro.report
    Kernel log(repro on Linux-v6.18): https://github.com/Wxm-233/KConfigFuzz_crashes/raw/refs/heads/main/8facfbb5acbe6b82e7b5bf8d27be8930172c96c1/repro_report0
    Reproduction C Code: https://github.com/Wxm-233/KConfigFuzz_crashes/raw/refs/heads/main/8facfbb5acbe6b82e7b5bf8d27be8930172c96c1/repro.cprog
    Syscall sequence for reproduction (more precise): https://github.com/Wxm-233/KConfigFuzz_crashes/raw/refs/heads/main/8facfbb5acbe6b82e7b5bf8d27be8930172c96c1/repro.prog
    GCC info: https://github.com/Wxm-233/KConfigFuzz_crashes/raw/refs/heads/main/0f85fc661af1e3c69b26b97eaaaa43d629de449c/gccinfo

I hope this report helps in identifying and resolving the issue. Thanks for your time and attention.

Best regards.