Hello,

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

KyongHo Cho [off-list ref] wrote @ Wed, 22 Aug 2012 14:47:00 +0200:

quoted

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