4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Nate Watterson <nwatters@xxxxxxxxxxxxxx>
[ 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@xxxxxxxxxxxxxx>
Signed-off-by: Will Deacon <will.deacon@xxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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
@@ -1033,13 +1033,8 @@ 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
@@ -1068,7 +1063,6 @@ 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) {