diff --git a/arch/x86_64/kernel/pci-gart.c b/arch/x86_64/kernel/pci-gart.c index 88be97c96987ad17edc63673b1134ffa4864b896..2e28e855ec3cff500847957a51251368407fbea3 100644 --- a/arch/x86_64/kernel/pci-gart.c +++ b/arch/x86_64/kernel/pci-gart.c @@ -220,6 +220,12 @@ dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle, uses the normal dma_mask for alloc_coherent. */ dma_mask &= *dev->dma_mask; + /* Why <=? Even when the mask is smaller than 4GB it is often larger + than 16MB and in this case we have a chance of finding fitting memory + in the next higher zone first. If not retry with true GFP_DMA. -AK */ + if (dma_mask <= 0xffffffff) + gfp |= GFP_DMA32; + again: memory = dma_alloc_pages(dev, gfp, get_order(size)); if (memory == NULL) @@ -245,7 +251,7 @@ dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle, } if (!(gfp & GFP_DMA)) { - gfp |= GFP_DMA; + gfp = (gfp & ~GFP_DMA32) | GFP_DMA; goto again; } return NULL;