diff options
Diffstat (limited to 'drivers/iommu/io-pgtable-arm-v7s.c')
-rw-r--r-- | drivers/iommu/io-pgtable-arm-v7s.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/drivers/iommu/io-pgtable-arm-v7s.c b/drivers/iommu/io-pgtable-arm-v7s.c index 690629457565..af330f513653 100644 --- a/drivers/iommu/io-pgtable-arm-v7s.c +++ b/drivers/iommu/io-pgtable-arm-v7s.c @@ -408,8 +408,12 @@ static arm_v7s_iopte arm_v7s_install_table(arm_v7s_iopte *table, if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_NS) new |= ARM_V7S_ATTR_NS_TABLE; - /* Ensure the table itself is visible before its PTE can be */ - wmb(); + /* + * Ensure the table itself is visible before its PTE can be. + * Whilst we could get away with cmpxchg64_release below, this + * doesn't have any ordering semantics when !CONFIG_SMP. + */ + dma_wmb(); old = cmpxchg_relaxed(ptep, curr, new); __arm_v7s_pte_sync(ptep, 1, cfg); |