Commit a2b89b59 authored Oct 23, 2008 by FUJITA Tomonori Committed by Ingo Molnar Oct 23, 2008

swiotlb: remove panic for alloc_coherent failure



swiotlb_alloc_coherent calls panic() when allocated swiotlb pages is
not fit for a device's dma mask. However, alloc_coherent failure is
not a disaster at all. AFAIK, none of other x86 and IA64 IOMMU
implementations don't crash in case of alloc_coherent failure.

There are some drivers that don't check alloc_coherent failure but not
many (about ten and I've already started to fix some of
them). alloc_coherent returns NULL in case of failure so it's likely
that these guilty drivers crash immediately. So swiotlb doesn't need
to call panic() just for them.

Reported-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Tested-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

parent ff3c5362

lib/swiotlb.c

+4 −2

Original line number	Diff line number	Diff line
		@@ -497,8 +497,10 @@ swiotlb_alloc_coherent(struct device *hwdev, size_t size,
		printk("hwdev DMA mask = 0x%016Lx, dev_addr = 0x%016Lx\n",
		(unsigned long long)*hwdev->dma_mask,
		(unsigned long long)dev_addr);
		panic("swiotlb_alloc_coherent: allocated memory is out of "
		"range for device");

		/* DMA_TO_DEVICE to avoid memcpy in unmap_single */
		unmap_single(hwdev, ret, size, DMA_TO_DEVICE);
		return NULL;
		}
		*dma_handle = dev_addr;
		return ret;

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