From 6d24250be6c315faec21e49d8888da684dbf47ec Mon Sep 17 00:00:00 2001
From: John Harrison <John.C.Harrison@Intel.com>
Date: Thu, 9 Dec 2021 20:40:22 -0800
Subject: drm/i915/guc: Don't go bang in GuC log if no GuC
Git-commit: 76aee8658b8f5836ace0a423157f29fcaec65e30
Patch-mainline: v5.17-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225
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@Intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211210044022.1842938-5-John.C.Harrison@Intel.com
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
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);
--
2.38.1