This is a note to let you know that I've just added the patch titled
iommu/arm-smmu-qcom: Fix mask extraction for bootloader programmed SMRs
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
iommu-arm-smmu-qcom-fix-mask-extraction-for-bootloader-programmed-smrs.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From dead723e6f049e9fb6b05e5b93456982798ea961 Mon Sep 17 00:00:00 2001
From: "Isaac J. Manjarres" <isaacm@xxxxxxxxxxxxxx>
Date: Mon, 25 Jan 2021 13:52:25 -0800
Subject: iommu/arm-smmu-qcom: Fix mask extraction for bootloader programmed SMRs
From: Isaac J. Manjarres <isaacm@xxxxxxxxxxxxxx>
commit dead723e6f049e9fb6b05e5b93456982798ea961 upstream.
When extracting the mask for a SMR that was programmed by the
bootloader, the SMR's valid bit is also extracted and is treated
as part of the mask, which is not correct. Consider the scenario
where an SMMU master whose context is determined by a bootloader
programmed SMR is removed (omitting parts of device/driver core):
->iommu_release_device()
-> arm_smmu_release_device()
-> arm_smmu_master_free_smes()
-> arm_smmu_free_sme() /* Assume that the SME is now free */
-> arm_smmu_write_sme()
-> arm_smmu_write_smr() /* Construct SMR value using mask and SID */
Since the valid bit was considered as part of the mask, the SMR will
be programmed as valid.
Fix the SMR mask extraction step for bootloader programmed SMRs
by masking out the valid bit when we know that we're already
working with a valid SMR.
Fixes: 07a7f2caaa5a ("iommu/arm-smmu-qcom: Read back stream mappings")
Signed-off-by: Isaac J. Manjarres <isaacm@xxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Reviewed-by: Robin Murphy <robin.murphy@xxxxxxx>
Link: https://lore.kernel.org/r/1611611545-19055-1-git-send-email-isaacm@xxxxxxxxxxxxxx
Signed-off-by: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 2 ++
1 file changed, 2 insertions(+)
--- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
@@ -65,6 +65,8 @@ static int qcom_smmu_cfg_probe(struct ar
smr = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_SMR(i));
if (FIELD_GET(ARM_SMMU_SMR_VALID, smr)) {
+ /* Ignore valid bit for SMR mask extraction. */
+ smr &= ~ARM_SMMU_SMR_VALID;
smmu->smrs[i].id = FIELD_GET(ARM_SMMU_SMR_ID, smr);
smmu->smrs[i].mask = FIELD_GET(ARM_SMMU_SMR_MASK, smr);
smmu->smrs[i].valid = true;
Patches currently in stable-queue which might be from isaacm@xxxxxxxxxxxxxx are
queue-5.10/iommu-arm-smmu-qcom-fix-mask-extraction-for-bootloader-programmed-smrs.patch
