drm/i915: Allow NULL memory region

Jonathan-Cavitt · tursulin · commit 26720dd2b5a1 · 2024-07-23T09:34:13.000Z
Prevent a NULL pointer access in intel_memory_regions_hw_probe. Fixes: 05da7d9 ("drm/i915/gem: Downgrade stolen lmem setup warning") Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/11704 Signed-off-by: Jonathan Cavitt <jonathan.cavitt@intel.com> Reviewed-by: Nirmoy Das <nirmoy.das@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20240712214156.3969584-1-jonathan.cavitt@intel.com (cherry picked from commit d75dec1) Signed-off-by: Tvrtko Ursulin <tursulin@ursulin.net>
diff --git a/drivers/gpu/drm/i915/intel_memory_region.c b/drivers/gpu/drm/i915/intel_memory_region.c
@@ -368,8 +368,10 @@ int intel_memory_regions_hw_probe(struct drm_i915_private *i915)
 			goto out_cleanup;
 		}
 
-		mem->id = i;
-		i915->mm.regions[i] = mem;
+		if (mem) { /* Skip on non-fatal errors */
+			mem->id = i;
+			i915->mm.regions[i] = mem;
+		}
 	}
 
 	for (i = 0; i < ARRAY_SIZE(i915->mm.regions); i++) {

Original file line number	Diff line number	Diff line change
`@@ -368,8 +368,10 @@ int intel_memory_regions_hw_probe(struct drm_i915_private *i915)`
`368`	`368`	`goto out_cleanup;`
`369`	`369`	`}`
`370`	`370`
`371`		`- mem->id = i;`
`372`		`- i915->mm.regions[i] = mem;`
	`371`	`+ if (mem) { /* Skip on non-fatal errors */`
	`372`	`+ mem->id = i;`
	`373`	`+ i915->mm.regions[i] = mem;`
	`374`	`+ }`
`373`	`375`	`}`
`374`	`376`
`375`	`377`	`for (i = 0; i < ARRAY_SIZE(i915->mm.regions); i++) {`