Hi Mukesh, On Sun, Sep 20, 2026 at 1:19 PM Mukesh Ojha <[email protected]> wrote: > > 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 v7: > - Since qcom_scm_pas_context is removed, v6 needs to be rebased removing > the changes related to it. > - Link to v6: > https://lore.kernel.org/lkml/[email protected]/ >
Please update the commit message to use qcom_pas_context instead. Also, why don't we handle this case in the generic PAS wrapper since it sounds like it would affect OP-TEE backend too? -Sumit > 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 + > 3 files changed, 11 insertions(+), 3 deletions(-) > > diff --git a/drivers/firmware/qcom/qcom_scm.c > b/drivers/firmware/qcom/qcom_scm.c > index 28411a76d1bf..81bb38401d54 100644 > --- a/drivers/firmware/qcom/qcom_scm.c > +++ b/drivers/firmware/qcom/qcom_scm.c > @@ -625,7 +625,7 @@ 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; > @@ -664,9 +664,13 @@ static int qcom_scm_pas_init_image(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 96a2436b777d..40cd0f101a67 100644 > --- a/drivers/remoteproc/qcom_q6v5_pas.c > +++ b/drivers/remoteproc/qcom_q6v5_pas.c > @@ -733,6 +733,7 @@ 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; > > @@ -751,6 +752,8 @@ 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) > -- > 2.55.0 >
