[PATCH v2 3/3] firmware: qcom_scm: align PAS resource table retry

[Mukesh Ojha <mukesh.ojha@oss.qualcomm.com>]

The initial PAS resource-table buffer can be too small. TrustZone
returns the required size and the wrapper retries the SCM call.
Although qcom_tzmem_alloc() aligns the allocated buffer,
the size passed to TrustZone remained unaligned.

Align the retry size to a page boundary so that both the buffer
and its advertised size satisfy the PAS/TrustZone contract.

Fixes: 8b9d2050cfa0 ("firmware: qcom_scm: Add qcom_scm_pas_get_rsc_table() to get resource table")
Signed-off-by: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com>
---
Changes in v2:
 - New change.

 drivers/firmware/qcom/qcom_scm.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c
index b5959f833dd7..f4442a70e614 100644
--- a/drivers/firmware/qcom/qcom_scm.c
+++ b/drivers/firmware/qcom/qcom_scm.c
@@ -812,12 +812,14 @@ static void *qcom_scm_pas_get_rsc_table(struct device *dev,
 	output_rt_tzm = __qcom_scm_pas_get_rsc_table(dev, ctx->pas_id,
 						     input_rt_tzm,
 						     input_rt_size, &size);
-	if (PTR_ERR(output_rt_tzm) == -EOVERFLOW)
-		/* Try again with the size requested by the TZ */
+	if (PTR_ERR(output_rt_tzm) == -EOVERFLOW) {
+		/* Try again with a page-aligned size requested by the TZ. */
+		size = PAGE_ALIGN(size);
 		output_rt_tzm = __qcom_scm_pas_get_rsc_table(dev, ctx->pas_id,
 							     input_rt_tzm,
 							     input_rt_size,
 							     &size);
+	}
 	if (IS_ERR(output_rt_tzm)) {
 		ret = PTR_ERR(output_rt_tzm);
 		goto free_input_rt;
-- 
2.55.0