Re: [PATCH] SLUB: Don't drop __GFP_NOFAIL completely fromallocate_slab() (was: Re: [Bug #14265] ifconfig: page allocationfailure. order:5,ode:0x8020 w/ e100)

From: Karol Lewandowski
Date: Thu Oct 22 2009 - 17:34:03 EST


On Thu, Oct 22, 2009 at 11:20:14AM +0100, Mel Gorman wrote:
> On Wed, Oct 21, 2009 at 11:20:34PM +0200, Karol Lewandowski wrote:
> > > Note: slub isn't going to be a culprit in order 5 allocation failures
> > > since they have kmalloc passthrough to the page allocator.
> >
> > However, it might change fragmentation somewhat I guess. This might
> > make problem more/less visible.
> >
>
> Did you have CONFIG_KMEMCHECK set by any chance?

No, kmemcheck (and kmemleak) was always disabled.

It's likely that's possible to trigger allocation failures with slab,
I just haven't been successful at it. Lack of good testcase is really
problem here -- even if I can't trigger failures I can never be sure
that these wont appear in some strange moment.

BTW I'll test your patches (from another thread) shortly.

Thanks.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/