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    Subjectperf_event_mmap(vma) && !vma->vm_mm
    Hi,

    I am fighting with uprobe bug, and perf_event_mmap() complicates
    the problem, it is the only reason (afaics) why the forking task
    can not do install_special_mapping(new_child_mm). This means that
    the child should do this itself, say, from task_work_run() but
    this way it can't handle the error if get_xol_area() fails, too
    late to abort the already finished copy_process().

    But please ignore, the only question is that I can't understand
    this

    if (!vma->vm_mm) {
    name = strncpy(tmp, "[vdso]", sizeof(tmp));
    goto got_name;
    }

    code in perf_event_mmap_event() and I am just curious. How it is
    possible that vma->vm_mm == NULL ? perf_event_mmap(vma) is never
    called with, say, vma == gate_vma. And even if it was possible
    arch_vma_name() should handle this case?

    Thanks,

    Oleg.



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