The PAS image initialization path always retains the metadata buffer when a valid qcom_scm_pas_context is provided, even if the caller does not require it. This implicit behavior leads to unclear buffer ownership and forces new users of qcom_mdt_pas_load() to manually release metadata, which is error‑ prone and incorrect.
Add a keep_mdt_buf flag to struct qcom_scm_pas_context to make metadata retention explicit. Metadata buffers are now freed by default and are only preserved when this flag is set. qcom_q6v5_pas enables this during probe for contexts that require retained metadata for subsequent PAS operations, while existing callers continue to work unchanged. Signed-off-by: Mukesh Ojha <[email protected]> --- Changes in v6: - Other patches from the series is merged. - Removed dependency on below series by adding keep_mdt_buf into qcom_scm_pas_context structure as well. https://lore.kernel.org/lkml/[email protected]/ - Addressed minor comment on the documentationi. - Link to v5: 6/6 of https://lore.kernel.org/lkml/[email protected]/ drivers/firmware/qcom/qcom_scm.c | 10 +++++++--- drivers/remoteproc/qcom_q6v5_pas.c | 3 +++ include/linux/firmware/qcom/qcom_pas.h | 1 + include/linux/firmware/qcom/qcom_scm.h | 1 + 4 files changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c index 3eaa4c9ccf3c..0528a15903c1 100644 --- a/drivers/firmware/qcom/qcom_scm.c +++ b/drivers/firmware/qcom/qcom_scm.c @@ -645,7 +645,7 @@ static int qcom_scm_pas_prep_and_init_image(struct device *dev, mdata_phys = qcom_tzmem_to_phys(mdata_buf); ret = __qcom_scm_pas_init_image(dev, ctx->pas_id, mdata_phys, &res); - if (ret < 0) + if (ret < 0 || !ctx->keep_mdt_buf) qcom_tzmem_free(mdata_buf); else ctx->ptr = mdata_buf; @@ -684,9 +684,13 @@ static int __qcom_scm_pas_init_image2(struct device *dev, u32 pas_id, memcpy(mdata_buf, metadata, size); ret = __qcom_scm_pas_init_image(dev, pas_id, mdata_phys, &res); - if (ret < 0 || !ctx) { + + /* + * free the metadata on error or if client didn't request us to keep it. + */ + if (ret < 0 || !ctx || !ctx->keep_mdt_buf) { dma_free_coherent(dev, size, mdata_buf, mdata_phys); - } else if (ctx) { + } else { ctx->ptr = mdata_buf; ctx->phys = mdata_phys; ctx->size = size; diff --git a/drivers/remoteproc/qcom_q6v5_pas.c b/drivers/remoteproc/qcom_q6v5_pas.c index ca8e61254c44..6aff24d56ea8 100644 --- a/drivers/remoteproc/qcom_q6v5_pas.c +++ b/drivers/remoteproc/qcom_q6v5_pas.c @@ -722,6 +722,7 @@ static int qcom_pas_alloc_memory_region(struct qcom_pas *pas) if (IS_ERR(pas->pas_ctx)) return PTR_ERR(pas->pas_ctx); + pas->pas_ctx->keep_mdt_buf = true; if (!pas->dtb_pas_id) return 0; @@ -740,6 +741,8 @@ static int qcom_pas_alloc_memory_region(struct qcom_pas *pas) if (IS_ERR(pas->dtb_pas_ctx)) return PTR_ERR(pas->dtb_pas_ctx); + pas->dtb_pas_ctx->keep_mdt_buf = true; + return 0; } diff --git a/include/linux/firmware/qcom/qcom_pas.h b/include/linux/firmware/qcom/qcom_pas.h index fb2ec3be6a16..1d132e89536e 100644 --- a/include/linux/firmware/qcom/qcom_pas.h +++ b/include/linux/firmware/qcom/qcom_pas.h @@ -22,6 +22,7 @@ struct qcom_pas_context { dma_addr_t phys; ssize_t size; bool use_tzmem; + bool keep_mdt_buf; }; static inline void __iomem *qcom_pas_ctx_map(struct qcom_pas_context *ctx) diff --git a/include/linux/firmware/qcom/qcom_scm.h b/include/linux/firmware/qcom/qcom_scm.h index 5747bd191bf1..6d8d3deb02e0 100644 --- a/include/linux/firmware/qcom/qcom_scm.h +++ b/include/linux/firmware/qcom/qcom_scm.h @@ -75,6 +75,7 @@ struct qcom_scm_pas_context { dma_addr_t phys; ssize_t size; bool use_tzmem; + bool keep_mdt_buf; }; struct qcom_scm_pas_context *devm_qcom_scm_pas_context_alloc(struct device *dev, -- 2.53.0
