[lkml]   [2012]   [Aug]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRE: [RFC 2/4] ARM: dma-mapping: IOMMU allocates pages from pool with GFP_ATOMIC

On Wednesday, August 22, 2012 3:37 PM Hiroshi Doyu wrote:

> KyongHo Cho <> wrote @ Wed, 22 Aug 2012 14:47:00 +0200:
> > vzalloc() call in __iommu_alloc_buffer() also causes BUG() in atomic context.
> Right.
> I've been thinking that kzalloc() may be enough here, since
> vzalloc() was introduced to avoid allocation failure for big chunk of
> memory, but I think that it's unlikely that the number of page array
> can be so big. So I propose to drop vzalloc() here, and just simply to
> use kzalloc only as below(*1).

We already had a discussion about this, so I don't think it makes much sense to
change it back to kzalloc. This vmalloc() call won't hurt anyone. It should not
be considered a problem for atomic allocations, because no sane driver will try
to allocate buffers larger than a dozen KiB with GFP_ATOMIC flag. I would call
such try a serious bug, which we should not care here.

Best regards
Marek Szyprowski
Samsung Poland R&D Center

 \ /
  Last update: 2012-08-23 08:41    [W:0.045 / U:9.224 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site