[Intel-gfx] [PATCH 1/2] drm/i915: Keep local modparams copy for mock selftests

[Jakub Bartmiński]

Some functions used within mock selftests may expect platform-dependent
automatic modparams parameters to have already been resolved, resulting
in failed assertions.
Backing up the modparams before mock selftests and manually setting
offending parameters inside the affected selftests should fix the issue.

Signed-off-by: Jakub Bartmiński <jakub.bartminski at intel.com>
Cc: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Michał Winiarski <michal.winiarski at intel.com>
---
 drivers/gpu/drm/i915/i915_pci.c                   | 10 ++++++++++
 drivers/gpu/drm/i915/selftests/i915_gem_context.c |  6 ++++++
 2 files changed, 16 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_pci.c b/drivers/gpu/drm/i915/i915_pci.c
index 55543f1b0236..9e41851f5ca2 100644
--- a/drivers/gpu/drm/i915/i915_pci.c
+++ b/drivers/gpu/drm/i915/i915_pci.c
@@ -733,11 +733,21 @@ static int __init i915_init(void)
 {
 	bool use_kms = true;
 	int err;
+	struct i915_params *backup_modparams;
+
+	backup_modparams = kmalloc(sizeof(*backup_modparams), GFP_KERNEL);
+	if (!backup_modparams)
+		return -ENOMEM;
+	memcpy(backup_modparams, &i915_modparams, sizeof(*backup_modparams));
 
 	err = i915_mock_selftests();
 	if (err)
 		return err > 0 ? 0 : err;
 
+	/* Revert any modparams modifications made inside mock selftests */
+	memcpy(&i915_modparams, backup_modparams, sizeof(*backup_modparams));
+	kfree(backup_modparams);
+
 	/*
 	 * Enable KMS by default, unless explicitly overriden by
 	 * either the i915.modeset prarameter or by the
diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_context.c b/drivers/gpu/drm/i915/selftests/i915_gem_context.c
index ab2590242033..de6aad832ac9 100644
--- a/drivers/gpu/drm/i915/selftests/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_context.c
@@ -597,6 +597,12 @@ int i915_gem_context_mock_selftests(void)
 	if (!i915)
 		return -ENOMEM;
 
+	/*
+	 * Platform defaults have not been resolved yet, so we need to prevent
+	 * assertion failure on an unresolved enable_guc.
+	 */
+	i915_modparams.enable_guc = 0;
+
 	err = i915_subtests(tests, i915);
 
 	drm_dev_put(&i915->drm);
-- 
2.17.1