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| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2015-07-27 13:29:00 +0100 |
|---|---|---|
| committer | Thierry Reding <treding@nvidia.com> | 2015-08-13 16:06:36 +0200 |
| commit | 9113785c3e918187b6b0c084c60e0344a2f1685c (patch) | |
| tree | 7e22a7c742ca5cab5524fa2fabae496a4a6950fd /drivers/iommu/tegra-smmu.c | |
| parent | d770e558e21961ad6cfdf0ff7df0eb5d7d4f0754 (diff) | |
| download | linux-9113785c3e918187b6b0c084c60e0344a2f1685c.tar.gz linux-9113785c3e918187b6b0c084c60e0344a2f1685c.tar.bz2 linux-9113785c3e918187b6b0c084c60e0344a2f1685c.zip | |
iommu/tegra-smmu: Fix iova_to_phys() method
iova_to_phys() has several problems:
(a) iova_to_phys() is supposed to return 0 if there is no entry present
for the iova.
(b) if as_get_pte() fails, we oops the kernel by dereferencing a NULL
pointer. Really, we should not even be trying to allocate a page
table at all, but should only be returning the presence of the 2nd
level page table. This will be fixed in a subsequent patch.
Treat both of these conditions as "no mapping" conditions.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Diffstat (limited to 'drivers/iommu/tegra-smmu.c')
| -rw-r--r-- | drivers/iommu/tegra-smmu.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c index c1f2e521dc52..083354903a1a 100644 --- a/drivers/iommu/tegra-smmu.c +++ b/drivers/iommu/tegra-smmu.c @@ -592,6 +592,9 @@ static phys_addr_t tegra_smmu_iova_to_phys(struct iommu_domain *domain, u32 *pte; pte = as_get_pte(as, iova, &page); + if (!pte || !*pte) + return 0; + pfn = *pte & as->smmu->pfn_mask; return PFN_PHYS(pfn); |