redonkable/remarkable-linux
redonkable/remarkable-linux
1
0
Fork 0
Code Releases Activity

ARM: 8305/1: DMA: Fix kzalloc flags in __iommu_alloc_buffer()

Browse source 
There doesn't seem to be any valid reason to allocate the pages array
with the same flags as the buffer itself. Doing so can eventually lead
to the following safeguard in mm/slab.c's cache_grow() to be hit:

        if (unlikely(flags & GFP_SLAB_BUG_MASK)) {
                pr_emerg("gfp: %un", flags & GFP_SLAB_BUG_MASK);
                BUG();
        }

This happens when buffers are allocated with __GFP_DMA32 or
__GFP_HIGHMEM.

Fix this by allocating the pages array with GFP_KERNEL to follow what is
done elsewhere in this file. Using GFP_KERNEL in __iommu_alloc_buffer()
is safe because atomic allocations are handled by __iommu_alloc_atomic().

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Alexandre Courbot 2015-02-19 07:29:58 +01:00 committed by Russell King
parent 8e64806672
commit 23be7fdafa
1 changed files with 1 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
arch/arm/mm/dma-mapping.c
View file

@ -1106,7 +1106,7 @@ static struct page **__iommu_alloc_buffer(struct device *dev, size_t size,
int i = 0;
if (array_size <= PAGE_SIZE)
pages = kzalloc(array_size, gfp);
pages = kzalloc(array_size, GFP_KERNEL);
else
pages = vzalloc(array_size);
if (!pages)