From: Arnd Bergmann <arnd@arndb.de>
Date: Thu, 15 Mar 2018 17:49:40 +0100
Subject: drm/amdkfd: fix uninitialized variable use
Git-commit: 48a44387189ce575cbfe48b5467884b6576cdaf2
Patch-mainline: v4.17-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166

When CONFIG_ACPI is disabled, we never initialize the acpi_table
structure in kfd_create_crat_image_virtual:

drivers/gpu/drm/amd/amdkfd/kfd_crat.c: In function 'kfd_create_crat_image_virtual':
drivers/gpu/drm/amd/amdkfd/kfd_crat.c:888:40: error: 'acpi_table' may be used uninitialized in this function [-Werror=maybe-uninitialized]

The undefined behavior also happens for any other acpi_get_table()
failure, but then the compiler can't warn about it.

This adds an error check that prevents the structure from
being used in error, avoiding both the undefined behavior and
the warning about it.

Fixes: 520b8fb755cc ("drm/amdkfd: Add topology support for CPUs")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 drivers/gpu/drm/amd/amdkfd/kfd_crat.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/gpu/drm/amd/amdkfd/kfd_crat.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_crat.c
@@ -882,7 +882,7 @@ static int kfd_create_vcrat_image_cpu(vo
 	crat_table->length = sizeof(struct crat_header);
 
 	status = acpi_get_table("DSDT", 0, &acpi_table);
-	if (status == AE_NOT_FOUND)
+	if (status != AE_OK)
 		pr_warn("DSDT table not found for OEM information\n");
 	else {
 		crat_table->oem_revision = acpi_table->revision;