4.9-stable review patch. If anyone has any objections, please let me know.
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From: Nate Watterson nwatters@codeaurora.org
[ Upstream commit 810871c57011eb3e89e6768932757f169d666cd2 ]
To prevent corruption of the stage-1 context pointer field when updating STEs, rebuild the entire containing dword instead of clearing individual fields.
Signed-off-by: Nate Watterson nwatters@codeaurora.org Signed-off-by: Will Deacon will.deacon@arm.com Signed-off-by: Sasha Levin alexander.levin@verizon.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/iommu/arm-smmu-v3.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-)
--- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -1040,13 +1040,8 @@ static void arm_smmu_write_strtab_ent(st } }
- /* Nuke the existing Config, as we're going to rewrite it */ - val &= ~(STRTAB_STE_0_CFG_MASK << STRTAB_STE_0_CFG_SHIFT); - - if (ste->valid) - val |= STRTAB_STE_0_V; - else - val &= ~STRTAB_STE_0_V; + /* Nuke the existing STE_0 value, as we're going to rewrite it */ + val = ste->valid ? STRTAB_STE_0_V : 0;
if (ste->bypass) { val |= disable_bypass ? STRTAB_STE_0_CFG_ABORT @@ -1081,7 +1076,6 @@ static void arm_smmu_write_strtab_ent(st val |= (ste->s1_cfg->cdptr_dma & STRTAB_STE_0_S1CTXPTR_MASK << STRTAB_STE_0_S1CTXPTR_SHIFT) | STRTAB_STE_0_CFG_S1_TRANS; - }
if (ste->s2_cfg) {