Re: [PATCH] uprobes: wait for mmap_sem for write killable

From: Oleg Nesterov
Date: Mon Feb 29 2016 - 13:11:19 EST


On 02/29, Michal Hocko wrote:
>
> --- a/kernel/events/uprobes.c
> +++ b/kernel/events/uprobes.c
> @@ -1130,7 +1130,9 @@ static int xol_add_vma(struct mm_struct *mm, struct xol_area *area)
> struct vm_area_struct *vma;
> int ret;
>
> - down_write(&mm->mmap_sem);
> + if (down_write_killable(&mm->mmap_sem))
> + return -EINTR;
> +
> if (mm->uprobes_state.xol_area) {
> ret = -EALREADY;
> goto fail;
> @@ -1468,7 +1470,8 @@ static void dup_xol_work(struct callback_head *work)
> if (current->flags & PF_EXITING)
> return;
>
> - if (!__create_xol_area(current->utask->dup_xol_addr))
> + if (!__create_xol_area(current->utask->dup_xol_addr) &&
> + !fatal_signal_pending(current)
> uprobe_warn(current, "dup xol area");
> }

Looks good, thanks.

Oleg.