[PATCH v5] misc: fastrpc: check qcom_scm_assign_mem() return in rpmsg_probe

[Xingjing Deng]

In the SDSP probe path, qcom_scm_assign_mem() is used to assign the
reserved memory to the configured VMIDs, but its return value was not
checked.

Fail the probe if the SCM call fails to avoid continuing with an
unexpected/incorrect memory permission configuration.

The file has passed the check of checkpatch.

Fixes: c3c0363bc72d4 ("misc: fastrpc: support complete DMA pool access to the DSP")
Cc: stable@xxxxxxxxxxxxxxx # 6.11-rc1
Signed-off-by: Xingjing Deng <xjdeng@xxxxxxxxxxx>
---
v5:
- Squash the functional change and indentation fix into a single patch.
- Link to v4: https://lore.kernel.org/linux-arm-msm/2026011637-statute-showy-2c3f@gregkh/T/#t

v4:
- Format the indentation
- Link to v3: https://lore.kernel.org/linux-arm-msm/20260113084352.72itrloj5w7qb5o3@xxxxxxxxxxxxxxxxxxxxxxxxx/T/#t

v3:
- Add missing linux-kernel@xxxxxxxxxxxxxxx to cc list.
- Standarlize changelog placement/format.
- Link to v2: https://lore.kernel.org/linux-arm-msm/20260113063618.e2ke47gy3hnfi67e@xxxxxxxxxxxxxxxxxxxxxxxxx/T/#t

v2:
- Add Fixes: and Cc: stable tags.
- Link to v1: https://lore.kernel.org/linux-arm-msm/20260113022550.4029635-1-xjdeng@xxxxxxxxxxx/T/#u
---
 drivers/misc/fastrpc.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c
index fb3b54e05928..d9650efa443f 100644
--- a/drivers/misc/fastrpc.c
+++ b/drivers/misc/fastrpc.c
@@ -2338,8 +2338,13 @@ static int fastrpc_rpmsg_probe(struct rpmsg_device *rpdev)
 		if (!err) {
 			src_perms = BIT(QCOM_SCM_VMID_HLOS);
 
-			qcom_scm_assign_mem(res.start, resource_size(&res), &src_perms,
-				    data->vmperms, data->vmcount);
+			err = qcom_scm_assign_mem(res.start, resource_size(&res), &src_perms,
+					data->vmperms, data->vmcount);
+			if (err) {
+				dev_err(rdev, "Failed to assign memory phys 0x%llx size 0x%llx err %d",
+				    res.start, resource_size(&res), err);
+				goto err_free_data;
+			}
 		}
 
 	}
-- 
2.25.1