On 09/24, qiwu.chen wrote:
>
> +EXPORT_SYMBOL(get_vma_name);
Why?
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -3566,6 +3566,10 @@ static inline bool range_in_vma(struct vm_area_struct *vma,
> #ifdef CONFIG_MMU
> pgprot_t vm_get_page_prot(unsigned long vm_flags);
> void vma_set_page_prot(struct vm_area_struct *vma);
> +void get_vma_name(struct vm_area_struct *vma,
> + const struct path **path,
> + const char **name,
> + const char **name_fmt);
> #else
You didn't move get_vma_name() from fs/proc/task_mmu.c, so it also depends
on CONFIG_PROC_FS.
> +/*
> + * This function is called in panic proccess if the PANIC_PRINT_TASK_MAPS_INFO
> + * flag is specified in panic_print, which is helpful to debug panic issues due
> + * to an unhandled falut in user mode such as kill init.
> + */
> +static void dump_task_maps_info(struct task_struct *tsk)
> +{
> + struct pt_regs *user_ret = task_pt_regs(tsk);
> + struct mm_struct *mm = tsk->mm;
> + struct vm_area_struct *vma;
> +
> + if (!mm || !user_mode(user_ret))
> + return;
> +
> + pr_info("Dump task %s:%d maps start\n", tsk->comm, task_pid_nr(tsk));
> + mmap_read_lock(mm);
> + VMA_ITERATOR(vmi, mm, 0);
> + for_each_vma(vmi, vma) {
> + int flags = vma->vm_flags;
> + unsigned long long pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
> + const struct path *path;
> + const char *name_fmt, *name;
> + char name_buf[SZ_256];
> +
> + get_vma_name(vma, &path, &name, &name_fmt);
So this code won't compile if CONFIG_MMU=n ?
> + if (path) {
> + name = d_path(path, name_buf, sizeof(name_buf));
> + name = IS_ERR(name) ? "?" : name;
perhaps this needs mangle_path() ...
> + } else if (name || name_fmt) {
> + snprintf(name_buf, sizeof(name_buf), name_fmt ?: "%s", name);
> + name = name_buf;
> + }
Why not
} else if (name_fmt) {
snprintf(name_buf, sizeof(name_buf), name_fmt, name);
name = name_buf;
}
?
> + if (name)
> + pr_info("%08lx-%08lx %c%c%c%c %08llx %s\n",
> + vma->vm_start, vma->vm_end,
> + flags & VM_READ ? 'r' : '-',
> + flags & VM_WRITE ? 'w' : '-',
> + flags & VM_EXEC ? 'x' : '-',
> + flags & VM_MAYSHARE ? 's' : 'p',
> + pgoff, name);
I don't really understand why you skip vma if !name...
Oleg.
