From: Mitchel Humpherys Date: Wed, 23 Sep 2015 20:56:27 +0000 (-0700) Subject: iommu/io-pgtable-arm: Stricter double-map checking X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=16135b65406895cc3ab28f39ccd5c2b44cd1aa94;p=sagit-ice-cold%2Fkernel_xiaomi_msm8998.git iommu/io-pgtable-arm: Stricter double-map checking Currently there's a check to make sure that a mapping isn't being installed on top of an existing leaf mapping. However, mapping on top of an existing table mapping is silently ignored. Make the check more strict by testing for any valid page table entry (table, block, or page descriptor) and by making any overlap fatal. Change-Id: Ibdffbfdb2b44cf9da5044c2c1828a32979a39760 Signed-off-by: Mitchel Humpherys --- diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c index 9876f6b6a674..90d0438a47ed 100644 --- a/drivers/iommu/io-pgtable-arm.c +++ b/drivers/iommu/io-pgtable-arm.c @@ -282,8 +282,8 @@ static int arm_lpae_init_pte(struct arm_lpae_io_pgtable *data, arm_lpae_iopte pte = prot; /* We require an unmap first */ - if (iopte_leaf(*ptep, lvl)) { - WARN_ON(!suppress_map_failures); + if (*ptep & ARM_LPAE_PTE_VALID) { + BUG_ON(!suppress_map_failures); return -EEXIST; }