Re: [PATCH 2/3] staging: lustre: lnet: Allocate MEs and small MDs in own kmem_caches

From: Greg Kroah-Hartman
Date: Thu Jun 09 2016 - 21:28:40 EST


On Thu, Jun 09, 2016 at 06:45:46PM -0400, James Simmons wrote:
> From: Bruno Faccini <bruno.faccini@xxxxxxxxx>
>
> As part of LU-3848 and LU-4330, it has been discovered that LNET
> MEs and small MDs (<=128 Bytes) are allocated in <size-128> kmem_cache
> and thus can suffer quite frequent corruptions, from other modules or
> Kernel parts, that occur there. To avoid this, MEs and small-MDs
> specific kmem_cache have been created.

What? Who corrupts them? That shouldn't be possible, and on some
systems, even if you do ask for a separate slab, it will be merged
togther with others of the same size. So this patch doesn't do all that
much.

I think you are having some other problem here, changing to a separate
memory cache shouldn't solve corruption issues.

sorry,

greg k-h