[PATCH 05/40] drm/i915: Handle incomplete Z_FINISH for compressed error states

[PATCH 05/40] drm/i915: Handle incomplete Z_FINISH for compressed error states

[Chris Wilson]

The final call to zlib_deflate(Z_FINISH) may require more output
space to be allocated and so needs to re-invoked. Failure to do so in
the current code leads to incomplete zlib streams (albeit intact due to
the use of Z_SYNC_FLUSH) resulting in the occasional short object
capture.

Testcase: igt/i915-error-capture.js
Fixes: 0a97015d45ee ("drm/i915: Compress GPU objects in error state")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: <stable@vger.kernel.org> # v4.10+
---
 drivers/gpu/drm/i915/i915_gpu_error.c | 60 +++++++++++++++++++++------
 1 file changed, 47 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index 2835cacd0d08..9789f4ff8c32 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -237,6 +237,7 @@ static int compress_page(struct compress *c,
 			 struct drm_i915_error_object *dst)
 {
 	struct z_stream_s *zstream = &c->zstream;
+	int flush = Z_NO_FLUSH;
 
 	zstream->next_in = src;
 	if (c->tmp && i915_memcpy_from_wc(c->tmp, src, PAGE_SIZE))
@@ -257,8 +258,11 @@ static int compress_page(struct compress *c,
 			zstream->avail_out = PAGE_SIZE;
 		}
 
-		if (zlib_deflate(zstream, Z_SYNC_FLUSH) != Z_OK)
+		if (zlib_deflate(zstream, flush) != Z_OK)
 			return -EIO;
+
+		if (zstream->avail_out)
+			flush = Z_SYNC_FLUSH;
 	} while (zstream->avail_in);
 
 	/* Fallback to uncompressed if we increase size? */
@@ -268,19 +272,43 @@ static int compress_page(struct compress *c,
 	return 0;
 }
 
-static void compress_fini(struct compress *c,
+static int compress_flush(struct compress *c,
 			  struct drm_i915_error_object *dst)
 {
 	struct z_stream_s *zstream = &c->zstream;
+	unsigned long page;
 
-	if (dst) {
-		zlib_deflate(zstream, Z_FINISH);
-		dst->unused = zstream->avail_out;
-	}
+	do {
+		switch (zlib_deflate(zstream, Z_FINISH)) {
+		case Z_OK: /* more space requested */
+			page = __get_free_page(GFP_ATOMIC | __GFP_NOWARN);
+			if (!page)
+				return -ENOMEM;
+
+			dst->pages[dst->page_count++] = (void *)page;
+			zstream->next_out = (void *)page;
+			zstream->avail_out = PAGE_SIZE;
+			break;
+		case Z_STREAM_END:
+			goto end;
+		default: /* any error */
+			return -EIO;
+		}
+	} while (1);
+
+end:
+	memset(zstream->next_out, 0, zstream->avail_out);
+	dst->unused = zstream->avail_out;
+	return 0;
+}
+
+static void compress_fini(struct compress *c,
+			  struct drm_i915_error_object *dst)
+{
+	struct z_stream_s *zstream = &c->zstream;
 
 	zlib_deflateEnd(zstream);
 	kfree(zstream->workspace);
-
 	if (c->tmp)
 		free_page((unsigned long)c->tmp);
 }
@@ -319,6 +347,12 @@ static int compress_page(struct compress *c,
 	return 0;
 }
 
+static int compress_flush(struct compress *c,
+			  struct drm_i915_error_object *dst)
+{
+	return 0;
+}
+
 static void compress_fini(struct compress *c,
 			  struct drm_i915_error_object *dst)
 {
@@ -951,15 +985,15 @@ i915_error_object_create(struct drm_i915_private *i915,
 		if (ret)
 			goto unwind;
 	}
-	goto out;
 
+	if (compress_flush(&compress, dst)) {
 unwind:
-	while (dst->page_count--)
-		free_page((unsigned long)dst->pages[dst->page_count]);
-	kfree(dst);
-	dst = NULL;
+		while (dst->page_count--)
+			free_page((unsigned long)dst->pages[dst->page_count]);
+		kfree(dst);
+		dst = NULL;
+	}
 
-out:
 	compress_fini(&compress, dst);
 	ggtt->vm.clear_range(&ggtt->vm, slot, PAGE_SIZE);
 	return dst;
-- 
2.19.0

[PATCH 35/40] drm/i915: Fix I915_EXEC_RING_MASK

[Chris Wilson]

This was supposed to be a mask of all known rings, but it is being used
by execbuffer to filter out invalid rings, and so is instead mapping high
unused values onto valid rings. Instead of a mask of all known rings,
we need it to be the mask of all possible rings.

Fixes: 549f7365820a ("drm/i915: Enable SandyBridge blitter ring")
Fixes: de1add360522 ("drm/i915: Decouple execbuf uAPI from internal implementation")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: <stable@vger.kernel.org> # v4.6+
---
 include/uapi/drm/i915_drm.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index adb9fed86ef7..65b0b84419f3 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -984,7 +984,7 @@ struct drm_i915_gem_execbuffer2 {
 	 * struct drm_i915_gem_exec_fence *fences.
 	 */
 	__u64 cliprects_ptr;
-#define I915_EXEC_RING_MASK              (7<<0)
+#define I915_EXEC_RING_MASK              (0x3f)
 #define I915_EXEC_DEFAULT                (0<<0)
 #define I915_EXEC_RENDER                 (1<<0)
 #define I915_EXEC_BSD                    (2<<0)
-- 
2.19.0

Re: [Intel-gfx] [PATCH 35/40] drm/i915: Fix I915_EXEC_RING_MASK

[Tvrtko Ursulin]

On 19/09/2018 20:55, Chris Wilson wrote:
> This was supposed to be a mask of all known rings, but it is being used
> by execbuffer to filter out invalid rings, and so is instead mapping high
> unused values onto valid rings. Instead of a mask of all known rings,
> we need it to be the mask of all possible rings.
> 
> Fixes: 549f7365820a ("drm/i915: Enable SandyBridge blitter ring")
> Fixes: de1add360522 ("drm/i915: Decouple execbuf uAPI from internal implementation")
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
> Cc: <stable@vger.kernel.org> # v4.6+
> ---
>   include/uapi/drm/i915_drm.h | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
> index adb9fed86ef7..65b0b84419f3 100644
> --- a/include/uapi/drm/i915_drm.h
> +++ b/include/uapi/drm/i915_drm.h
> @@ -984,7 +984,7 @@ struct drm_i915_gem_execbuffer2 {
>   	 * struct drm_i915_gem_exec_fence *fences.
>   	 */
>   	__u64 cliprects_ptr;
> -#define I915_EXEC_RING_MASK              (7<<0)
> +#define I915_EXEC_RING_MASK              (0x3f)
>   #define I915_EXEC_DEFAULT                (0<<0)
>   #define I915_EXEC_RENDER                 (1<<0)
>   #define I915_EXEC_BSD                    (2<<0)
> 

Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

Regards,

Tvrtko