From: Andi Kleen Date: Wed, 15 Aug 2007 00:40:34 +0000 (+0200) Subject: x86_64: Fail dma_alloc_coherent on dma less devices X-Git-Tag: v2.6.23-rc4~116 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8154549cb8ca795cbefda404cd6120398e5b145f;p=linux-2.6 x86_64: Fail dma_alloc_coherent on dma less devices This should fix an oops with PCMCIA PATA devices http://bugzilla.kernel.org/show_bug.cgi?id=8424 This is not a full fix for the problem, but probably still the right thing to do. [ I'm almost certain it's *not* the right thing to do, but it avoids an oops, and I want comments from others on what the right thing would actually be.. I suspect we should just remove the use of dma_mask entirely in this function, and just use coherent_dma_mask. - Linus ] Signed-off-by: Andi Kleen Signed-off-by: Linus Torvalds --- diff --git a/arch/x86_64/kernel/pci-dma.c b/arch/x86_64/kernel/pci-dma.c index 05d745ede5..29711445c8 100644 --- a/arch/x86_64/kernel/pci-dma.c +++ b/arch/x86_64/kernel/pci-dma.c @@ -82,6 +82,10 @@ dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle, if (dma_mask == 0) dma_mask = DMA_32BIT_MASK; + /* Device not DMA able */ + if (dev->dma_mask == NULL) + return NULL; + /* Don't invoke OOM killer */ gfp |= __GFP_NORETRY;