Re: ipc,sem: sysv semaphore scalability

[Linus Torvalds]

On Fri, Mar 29, 2013 at 9:17 AM, Dave Jones <davej@xxxxxxxxxx> wrote:
>
> Now that I have that reverted, I'm not seeing msgrcv traces any more, but
> I've started seeing this..
>
> general protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC

Do you have CONFIG_CHECKPOINT_RESTORE enabled? Does it go away if you
disable it?

I think I foud at least one bug in the MSG_COPY stuff: it leaks the
"copy" allocation if

    mode == SEARCH_LESSEQUAL

but maybe I'm misreading it. And that shouldn't cause the problem you
see, but it's indicative of how badly tested and thought through the
MSG_COPY code is.

Totally UNTESTED leak fix appended. Stanislav?

                     Linus

Attachment: patch.diff
Description: Binary data