Re: [PATCH v4 1/2] mm, proc: Fix region lost in /proc/self/smaps

[Oleg Nesterov]

On 10/01, Robert Ho wrote:
>
> --- a/fs/proc/task_mmu.c
> +++ b/fs/proc/task_mmu.c
> @@ -147,7 +147,7 @@ m_next_vma(struct proc_maps_private *priv, struct vm_area_struct *vma)
>  static void m_cache_vma(struct seq_file *m, struct vm_area_struct *vma)
>  {
>  	if (m->count < m->size)	/* vma is copied successfully */
> -		m->version = m_next_vma(m->private, vma) ? vma->vm_start : -1UL;
> +		m->version = m_next_vma(m->private, vma) ? vma->vm_end : -1UL;
>  }
>  
>  static void *m_start(struct seq_file *m, loff_t *ppos)
> @@ -175,8 +175,10 @@ static void *m_start(struct seq_file *m, loff_t *ppos)
>  	priv->tail_vma = get_gate_vma(mm);
>  
>  	if (last_addr) {
> -		vma = find_vma(mm, last_addr);
> -		if (vma && (vma = m_next_vma(priv, vma)))
> +		vma = find_vma(mm, last_addr - 1);
> +		if (vma && vma->vm_start <= last_addr)
> +			vma = m_next_vma(priv, vma);
> +		if (vma)
>  			return vma;
>  	}

Acked-by: Oleg Nesterov <oleg@xxxxxxxxxx>