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| author | Tushar Dave <tushar.n.dave@oracle.com> | 2017-07-11 14:34:47 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-07-12 08:13:04 -0700 |
| commit | 2ad67141f1e47dc063b202993835361a06239aaa (patch) | |
| tree | 72e0552f4322006d4474f46637e8ff55cee2b1f3 | |
| parent | 3b06b1a7448ee4e8e51dae3938774735404e51fb (diff) | |
| download | linux-stable-2ad67141f1e47dc063b202993835361a06239aaa.tar.gz linux-stable-2ad67141f1e47dc063b202993835361a06239aaa.tar.bz2 linux-stable-2ad67141f1e47dc063b202993835361a06239aaa.zip | |
SPARC64: Fix sun4v DMA panic
64bit DMA only supported on sun4v equipped with ATU IOMMU HW.
'Commit b02c2b0bfd7ae ("sparc: remove arch specific dma_supported
implementations")' introduced a code that incorrectly allow
dma_supported() to succeed for 64bit dma mask even if system doesn't
have ATU IOMMU. This results into panic.
Fix it.
Reported-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: Tushar Dave <tushar.n.dave@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | arch/sparc/kernel/pci_sun4v.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/arch/sparc/kernel/pci_sun4v.c b/arch/sparc/kernel/pci_sun4v.c index 24f21c726dfa..f10e2f712394 100644 --- a/arch/sparc/kernel/pci_sun4v.c +++ b/arch/sparc/kernel/pci_sun4v.c @@ -673,12 +673,14 @@ static void dma_4v_unmap_sg(struct device *dev, struct scatterlist *sglist, static int dma_4v_supported(struct device *dev, u64 device_mask) { struct iommu *iommu = dev->archdata.iommu; - u64 dma_addr_mask; + u64 dma_addr_mask = iommu->dma_addr_mask; - if (device_mask > DMA_BIT_MASK(32) && iommu->atu) - dma_addr_mask = iommu->atu->dma_addr_mask; - else - dma_addr_mask = iommu->dma_addr_mask; + if (device_mask > DMA_BIT_MASK(32)) { + if (iommu->atu) + dma_addr_mask = iommu->atu->dma_addr_mask; + else + return 0; + } if ((device_mask & dma_addr_mask) == dma_addr_mask) return 1; |