[PATCH 4/4] drm/i915/guc: Don't go bang in GuC log if no GuC

[Lucas De Marchi]

On Thu, Dec 02, 2021 at 04:06:23PM -0800, John.C.Harrison at Intel.com wrote:
>From: John Harrison <John.C.Harrison at Intel.com>
>
>If the GuC has failed to load for any reason and then the user pokes
>the debugfs GuC log interface, a BUG and/or null pointer deref can
>occur. Don't let that happen.
>
>Signed-off-by: John Harrison <John.C.Harrison at Intel.com>


Reviewed-by: Lucas De Marchi <lucas.demarchi at intel.com>

Lucas De Marchi

>---
> drivers/gpu/drm/i915/gt/uc/intel_guc_log_debugfs.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
>diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_log_debugfs.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_log_debugfs.c
>index 46026c2c1722..8fd068049376 100644
>--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_log_debugfs.c
>+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_log_debugfs.c
>@@ -31,7 +31,7 @@ static int guc_log_level_get(void *data, u64 *val)
> {
> 	struct intel_guc_log *log = data;
>
>-	if (!intel_guc_is_used(log_to_guc(log)))
>+	if (!log->vma)
> 		return -ENODEV;
>
> 	*val = intel_guc_log_get_level(log);
>@@ -43,7 +43,7 @@ static int guc_log_level_set(void *data, u64 val)
> {
> 	struct intel_guc_log *log = data;
>
>-	if (!intel_guc_is_used(log_to_guc(log)))
>+	if (!log->vma)
> 		return -ENODEV;
>
> 	return intel_guc_log_set_level(log, val);
>-- 
>2.25.1
>