tree 4c1d102f7214ba97b3a43a1af8ba9495e23f3d76
parent b34087157dd76e8d96e5e52808134a791ac61e57
author Robin Murphy <robin.murphy@arm.com> 1542816051 +0000
committer Christoph Hellwig <hch@lst.de> 1542822478 +0100

swiotlb: Skip cache maintenance on map error

If swiotlb_bounce_page() failed, calling arch_sync_dma_for_device() may
lead to such delights as performing cache maintenance on whatever
address phys_to_virt(SWIOTLB_MAP_ERROR) looks like, which is typically
outside the kernel memory map and goes about as well as expected.

Don't do that.

Fixes: a4a4330db46a ("swiotlb: add support for non-coherent DMA")
Tested-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>