From 6e1281412ab9e6772d8f6c26e592181fcdd2ae0c Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Tue, 14 Nov 2017 22:33:46 +0000
Subject: [PATCH] drm/i915/selftests: Always initialise err
Git-commit: 6e1281412ab9e6772d8f6c26e592181fcdd2ae0c
Patch-mainline: v4.16-rc1
References: FATE#322643 bsc#1055900

smatch does not track initialised values as well as gcc, and this
triggers many warnings by smatch not presented by gcc. Silence smatch by
initialising the error values to -ENODEV, which we use to denote
internal errors. (If we see a selftest fail with a silent -ENODEV, we
know smatch was right!)

V2: smatch was right about igt_create_vma(), it may unlikely fail on the
first object allocation which we want to be loud about.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171114223346.25958-1-chris@chris-wilson.co.uk
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/gpu/drm/i915/selftests/i915_gem_context.c  |    2 +-
 drivers/gpu/drm/i915/selftests/i915_gem_gtt.c      |    8 ++++----
 drivers/gpu/drm/i915/selftests/i915_gem_request.c  |    2 +-
 drivers/gpu/drm/i915/selftests/i915_gem_timeline.c |    2 +-
 drivers/gpu/drm/i915/selftests/i915_syncmap.c      |    6 +++---
 drivers/gpu/drm/i915/selftests/i915_vma.c          |    2 +-
 6 files changed, 11 insertions(+), 11 deletions(-)

--- a/drivers/gpu/drm/i915/selftests/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_context.c
@@ -325,7 +325,7 @@ static int igt_ctx_exec(void *arg)
 	LIST_HEAD(objects);
 	unsigned long ncontexts, ndwords, dw;
 	bool first_shared_gtt = true;
-	int err;
+	int err = -ENODEV;
 
 	/* Create a few different contexts (with different mm) and write
 	 * through each ctx/mm using the GPU making sure those writes end
--- a/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
@@ -699,7 +699,7 @@ static int drunk_hole(struct drm_i915_pr
 		unsigned int *order, count, n;
 		struct i915_vma *vma;
 		u64 hole_size;
-		int err;
+		int err = -ENODEV;
 
 		hole_size = (hole_end - hole_start) >> size;
 		if (hole_size > KMALLOC_MAX_SIZE / sizeof(u32))
@@ -958,7 +958,7 @@ static int exercise_ggtt(struct drm_i915
 	u64 hole_start, hole_end, last = 0;
 	struct drm_mm_node *node;
 	IGT_TIMEOUT(end_time);
-	int err;
+	int err = -ENODEV;
 
 	mutex_lock(&i915->drm.struct_mutex);
 restart:
@@ -1164,7 +1164,7 @@ static int igt_gtt_reserve(void *arg)
 	struct drm_i915_gem_object *obj, *on;
 	LIST_HEAD(objects);
 	u64 total;
-	int err;
+	int err = -ENODEV;
 
 	/* i915_gem_gtt_reserve() tries to reserve the precise range
 	 * for the node, and evicts if it has to. So our test checks that
@@ -1355,7 +1355,7 @@ static int igt_gtt_insert(void *arg)
 	}, *ii;
 	LIST_HEAD(objects);
 	u64 total;
-	int err;
+	int err = -ENODEV;
 
 	/* i915_gem_gtt_insert() tries to allocate some free space in the GTT
 	 * to the node, evicting if required.
--- a/drivers/gpu/drm/i915/selftests/i915_gem_request.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_request.c
@@ -332,7 +332,7 @@ static int live_nop_request(void *arg)
 	struct intel_engine_cs *engine;
 	struct live_test t;
 	unsigned int id;
-	int err;
+	int err = -ENODEV;
 
 	/* Submit various sized batches of empty requests, to each engine
 	 * (individually), and wait for the batch to complete. We can check
--- a/drivers/gpu/drm/i915/selftests/i915_gem_timeline.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_timeline.c
@@ -79,7 +79,7 @@ static int igt_sync(void *arg)
 	}, *p;
 	struct intel_timeline *tl;
 	int order, offset;
-	int ret;
+	int ret = -ENODEV;
 
 	tl = mock_timeline(0);
 	if (!tl)
--- a/drivers/gpu/drm/i915/selftests/i915_syncmap.c
+++ b/drivers/gpu/drm/i915/selftests/i915_syncmap.c
@@ -333,7 +333,7 @@ static int igt_syncmap_join_below(void *
 {
 	struct i915_syncmap *sync;
 	unsigned int step, order, idx;
-	int err;
+	int err = -ENODEV;
 
 	i915_syncmap_init(&sync);
 
@@ -402,7 +402,7 @@ static int igt_syncmap_neighbours(void *
 	I915_RND_STATE(prng);
 	IGT_TIMEOUT(end_time);
 	struct i915_syncmap *sync;
-	int err;
+	int err = -ENODEV;
 
 	/*
 	 * Each leaf holds KSYNCMAP seqno. Check that when we create KSYNCMAP
@@ -447,7 +447,7 @@ static int igt_syncmap_compact(void *arg
 {
 	struct i915_syncmap *sync;
 	unsigned int idx, order;
-	int err;
+	int err = -ENODEV;
 
 	i915_syncmap_init(&sync);
 
--- a/drivers/gpu/drm/i915/selftests/i915_vma.c
+++ b/drivers/gpu/drm/i915/selftests/i915_vma.c
@@ -150,7 +150,7 @@ static int igt_vma_create(void *arg)
 	IGT_TIMEOUT(end_time);
 	LIST_HEAD(contexts);
 	LIST_HEAD(objects);
-	int err;
+	int err = -ENOMEM;
 
 	/* Exercise creating many vma amonst many objections, checking the
 	 * vma creation and lookup routines.