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From 022131a879deb883f4fbbbd7b5887ae6b2738172 Mon Sep 17 00:00:00 2001
From: Eric Anholt <eric@anholt.net>
Date: Mon, 3 Dec 2018 14:24:38 -0800
Subject: [PATCH 578/703] drm/v3d: Invalidate the caches from the outside in.

This would be a fairly obscure race, but let's make sure we don't ever
lose it.

Signed-off-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20181203222438.25417-6-eric@anholt.net
Reviewed-by: Dave Emett <david.emett@broadcom.com>
(cherry picked from commit aa5beec32e8b78bfcf621e3c3daebfb1644b6365)
---
 drivers/gpu/drm/v3d/v3d_gem.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

--- a/drivers/gpu/drm/v3d/v3d_gem.c
+++ b/drivers/gpu/drm/v3d/v3d_gem.c
@@ -171,11 +171,15 @@ v3d_invalidate_slices(struct v3d_dev *v3
 void
 v3d_invalidate_caches(struct v3d_dev *v3d)
 {
+	/* Invalidate the caches from the outside in.  That way if
+	 * another CL's concurrent use of nearby memory were to pull
+	 * an invalidated cacheline back in, we wouldn't leave stale
+	 * data in the inner cache.
+	 */
 	v3d_flush_l3(v3d);
-
 	v3d_invalidate_l2c(v3d, 0);
-	v3d_invalidate_slices(v3d, 0);
 	v3d_flush_l2t(v3d, 0);
+	v3d_invalidate_slices(v3d, 0);
 }
 
 static void