On 09/14, Ben Wolsieffer wrote:
>
> Fixes: 47fecca15c09 ("fs/proc/task_nommu.c: don't use priv->task->mm")
> Signed-off-by: Ben Wolsieffer <ben.wolsieffer@xxxxxxxxxxx>
> ---
> fs/proc/task_nommu.c | 27 +++++++++++++++------------
> 1 file changed, 15 insertions(+), 12 deletions(-)
Acked-by: Oleg Nesterov <oleg@xxxxxxxxxx>
-------------------------------------------------------------------------------
Sorry for the offtopic question. I know NOTHING about nommu and when I tried to
review this patch I was puzzled by
/* See m_next(). Zero at the start or after lseek. */
if (addr == -1UL)
return NULL;
at the start of m_start(). OK, lets look at
static void *m_next(struct seq_file *m, void *_p, loff_t *pos)
{
struct vm_area_struct *vma = _p;
*pos = vma->vm_end;
return find_vma(vma->vm_mm, vma->vm_end);
}
where does this -1UL come from? Does this mean that on nommu
last_vma->vm_end == -1UL
or what?
fs/proc/task_mmu.c has the same check at the start, but in this case
the "See m_next()" comment actually helps.
Just curious, thanks.
Oleg.
