releases/4.18.19/soc-qcom-rmtfs-mem-validate-that-scm-is-available.patch

From 137dc5843faeacabf48fc22a8dc58c4e0b4f0927 Mon Sep 17 00:00:00 2001
From: Bjorn Andersson <bjorn.andersson@linaro.org>
Date: Mon, 27 Aug 2018 22:05:48 -0700
Subject: soc: qcom: rmtfs-mem: Validate that scm is available

From: Bjorn Andersson <bjorn.andersson@linaro.org>

commit 137dc5843faeacabf48fc22a8dc58c4e0b4f0927 upstream.

The scm device must be present in order for the rmtfs driver to
configure memory permissions for the rmtfs memory region, so check that
it is probed before continuing.

Cc: stable@vger.kernel.org
Fixes: fa65f8045137 ("soc: qcom: rmtfs-mem: Add support for assigning memory to remote")
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Andy Gross <andy.gross@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/soc/qcom/rmtfs_mem.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/drivers/soc/qcom/rmtfs_mem.c
+++ b/drivers/soc/qcom/rmtfs_mem.c
@@ -212,6 +212,11 @@ static int qcom_rmtfs_mem_probe(struct p
 		dev_err(&pdev->dev, "failed to parse qcom,vmid\n");
 		goto remove_cdev;
 	} else if (!ret) {
+		if (!qcom_scm_is_available()) {
+			ret = -EPROBE_DEFER;
+			goto remove_cdev;
+		}
+
 		perms[0].vmid = QCOM_SCM_VMID_HLOS;
 		perms[0].perm = QCOM_SCM_PERM_RW;
 		perms[1].vmid = vmid;