6.1-stable review patch. If anyone has any objections, please let me know.
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From: AngeloGioacchino Del Regno angelogioacchino.delregno@collabora.com
[ Upstream commit ec5601661bfcdc206e6ceba1b97837e763dab1ba ]
This driver was indexing the contexts by asid-1, which is probably done under the assumption that the first ASID is always 1. Unfortunately this is not always true: at least for MSM8956 and MSM8976's GPU IOMMU, the gpu_user context's ASID number is zero. To allow using a zero asid number, index the contexts by `asid` instead of by `asid - 1`.
While at it, also enhance human readability by renaming the `num_ctxs` member of struct qcom_iommu_dev to `max_asid`.
Signed-off-by: AngeloGioacchino Del Regno angelogioacchino.delregno@collabora.com Reviewed-by: Konrad Dybcio konrad.dybcio@linaro.org Link: https://lore.kernel.org/r/20230622092742.74819-5-angelogioacchino.delregno@c... Signed-off-by: Will Deacon will@kernel.org Stable-dep-of: 6a3908ce56e6 ("iommu/qcom: fix device leak on of_xlate()") Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/iommu/arm/arm-smmu/qcom_iommu.c | 22 ++++++++++------------ 1 file changed, 10 insertions(+), 12 deletions(-)
--- a/drivers/iommu/arm/arm-smmu/qcom_iommu.c +++ b/drivers/iommu/arm/arm-smmu/qcom_iommu.c @@ -51,8 +51,8 @@ struct qcom_iommu_dev { struct clk_bulk_data clks[CLK_NUM]; void __iomem *local_base; u32 sec_id; - u8 num_ctxs; - struct qcom_iommu_ctx *ctxs[]; /* indexed by asid-1 */ + u8 max_asid; + struct qcom_iommu_ctx *ctxs[]; /* indexed by asid */ };
struct qcom_iommu_ctx { @@ -94,7 +94,7 @@ static struct qcom_iommu_ctx * to_ctx(st struct qcom_iommu_dev *qcom_iommu = d->iommu; if (!qcom_iommu) return NULL; - return qcom_iommu->ctxs[asid - 1]; + return qcom_iommu->ctxs[asid]; }
static inline void @@ -559,12 +559,10 @@ static int qcom_iommu_of_xlate(struct de qcom_iommu = platform_get_drvdata(iommu_pdev);
/* make sure the asid specified in dt is valid, so we don't have - * to sanity check this elsewhere, since 'asid - 1' is used to - * index into qcom_iommu->ctxs: + * to sanity check this elsewhere: */ - if (WARN_ON(asid < 1) || - WARN_ON(asid > qcom_iommu->num_ctxs) || - WARN_ON(qcom_iommu->ctxs[asid - 1] == NULL)) { + if (WARN_ON(asid > qcom_iommu->max_asid) || + WARN_ON(qcom_iommu->ctxs[asid] == NULL)) { put_device(&iommu_pdev->dev); return -EINVAL; } @@ -722,7 +720,7 @@ static int qcom_iommu_ctx_probe(struct p
dev_dbg(dev, "found asid %u\n", ctx->asid);
- qcom_iommu->ctxs[ctx->asid - 1] = ctx; + qcom_iommu->ctxs[ctx->asid] = ctx;
return 0; } @@ -734,7 +732,7 @@ static void qcom_iommu_ctx_remove(struct
platform_set_drvdata(pdev, NULL);
- qcom_iommu->ctxs[ctx->asid - 1] = NULL; + qcom_iommu->ctxs[ctx->asid] = NULL; }
static const struct of_device_id ctx_of_match[] = { @@ -781,11 +779,11 @@ static int qcom_iommu_device_probe(struc for_each_child_of_node(dev->of_node, child) max_asid = max(max_asid, get_asid(child));
- qcom_iommu = devm_kzalloc(dev, struct_size(qcom_iommu, ctxs, max_asid), + qcom_iommu = devm_kzalloc(dev, struct_size(qcom_iommu, ctxs, max_asid + 1), GFP_KERNEL); if (!qcom_iommu) return -ENOMEM; - qcom_iommu->num_ctxs = max_asid; + qcom_iommu->max_asid = max_asid; qcom_iommu->dev = dev;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);