Re: oops in copy_page_rep()

[Linus Torvalds]

On Tue, Jan 8, 2013 at 9:37 AM, Andrea Arcangeli <aarcange@xxxxxxxxxx> wrote:
>
> The reason it returned to userland and retried the fault is that this
> should be infrequent enough not to worry about it and this was
> marginally simpler but it could be changed.

Yeah, that was my suspicion. And as mentioned, returning to user land
might actually help with scheduling and/or signal handling latencies
etc, so it might be the right thing to do.  Especially if the
alternative is to just busy-loop.

> If we don't want to return to userland we should wait on the splitting
> bit and then take the pte walking routines like if the pmd wasn't
> huge. This is not related to the below though.

How does this patch sound to people? It does the splitting check
before the access bit set (even though I don't think it matters), and
at least talks about the alternatives and the issues a bit.

Hmm?

                 Linus

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