Messages in this thread | | | From | Marek Szyprowski <> | Subject | RE: [RFC 0/4] ARM: dma-mapping: IOMMU atomic allocation | Date | Wed, 22 Aug 2012 14:04:26 +0200 |
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Hi Hiroshi,
On Wednesday, August 22, 2012 12:20 PM Hiroshi Doyu wrote:
> The commit e9da6e9 "ARM: dma-mapping: remove custom consistent dma > region" breaks the compatibility with existing drivers. This causes > the following kernel oops(*1). That driver has called dma_pool_alloc() > to allocate memory from the interrupt context, and it hits > BUG_ON(in_interrpt()) in "get_vm_area_caller()". This patch seris > fixes this problem with making use of the pre-allocate atomic memory > pool which DMA is using in the same way as DMA does now. > > Any comment would be really appreciated.
I was working on the similar patches, but You were faster. ;-)
Basically the patch no 1 and 2 are fine, but I don't like the changes proposed in patch 3 and 4. You should not alter the attributes provided by the user nor make any assumptions that such attributes has been provided - drivers are allowed to call dma_alloc_attrs() directly. Please rework your patches to avoid such approach.
Best regards -- Marek Szyprowski Samsung Poland R&D Center
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