Messages in this thread | | | Date | Wed, 1 Oct 2014 11:13:23 +0100 | From | Will Deacon <> | Subject | Re: [PATCH] arm64: Use and error-check DMA_ERROR_CODE |
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Hi Sean,
On Tue, Sep 30, 2014 at 09:15:21PM +0100, Sean Paul wrote: > This patch replaces the static assignment of ~0 to dma_handle with > DMA_ERROR_CODE to be consistent with other platforms. > > In addition to that, it also adds a check for DMA_ERROR_CODE before > calling __dma_free_coherent with an invalid dma_handle. > > Signed-off-by: Sean Paul <seanpaul@chromium.org> > --- > arch/arm64/mm/dma-mapping.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c > index 4164c5a..69fd2c4 100644 > --- a/arch/arm64/mm/dma-mapping.c > +++ b/arch/arm64/mm/dma-mapping.c > @@ -125,7 +125,7 @@ static void *__dma_alloc_noncoherent(struct device *dev, size_t size, > no_map: > __dma_free_coherent(dev, size, ptr, *dma_handle, attrs); > no_mem: > - *dma_handle = ~0; > + *dma_handle = DMA_ERROR_CODE; > return NULL; > } > > @@ -136,7 +136,9 @@ static void __dma_free_noncoherent(struct device *dev, size_t size, > void *swiotlb_addr = phys_to_virt(dma_to_phys(dev, dma_handle)); > > vunmap(vaddr); > - __dma_free_coherent(dev, size, swiotlb_addr, dma_handle, attrs); > + > + if (dma_handle != DMA_ERROR_CODE) > + __dma_free_coherent(dev, size, swiotlb_addr, dma_handle, attrs);
Is it legal to try and free a DMA buffer after a failed allocation? If so, I think we need something similar for arch/arm/.
Will
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