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Revert "iommu/amd: Don't allocate with __GFP_ZERO in alloc_coherent"

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This reverts commit 5fc872c7323534e8f7dc21bab635e7a9b9659e07.

The DMA-API does not strictly require that the memory
returned by dma_alloc_coherent is zeroed out. For that
another function (dma_zalloc_coherent) should be used. But
all other x86 DMA-API implementation I checked zero out the
memory, so that some drivers rely on it and break when it is
not.

It seems the (driver-)world is not yet ready for this
change, so revert it.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Joerg Roedel 2015-06-01 17:30:57 +02:00
parent c65b99f046
commit 2d0ec7a19b
1 changed files with 1 additions and 0 deletions
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drivers/iommu/amd_iommu.c
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@ -2930,6 +2930,7 @@ static void *alloc_coherent(struct device *dev, size_t size,
size = PAGE_ALIGN(size);
dma_mask = dev->coherent_dma_mask;
flag &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
flag |= __GFP_ZERO;
page = alloc_pages(flag | __GFP_NOWARN, get_order(size));
if (!page) {