From: Thomas Hellstrom <thellstrom@vmware.com>
Date: Wed, 5 Feb 2014 08:18:26 +0000 (+0100)
Subject: drm/ttm: Don't clear page metadata of imported sg pages
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=1b76af5ce8deb1c775ad1674bd249d782b5b13d9;p=linux-beck.git

drm/ttm: Don't clear page metadata of imported sg pages

These page pointers shouldn't be visible to TTM in the first place, but
until we fix that up, don't clear the page metadata because that
will upset the exporter.

Reported-and-tested-by: Cristoph Haag <haagch.christoph@googleemail.com>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
---

diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c
index 9af99084b344..75f319090043 100644
--- a/drivers/gpu/drm/ttm/ttm_tt.c
+++ b/drivers/gpu/drm/ttm/ttm_tt.c
@@ -380,6 +380,9 @@ static void ttm_tt_clear_mapping(struct ttm_tt *ttm)
 	pgoff_t i;
 	struct page **page = ttm->pages;
 
+	if (ttm->page_flags & TTM_PAGE_FLAG_SG)
+		return;
+
 	for (i = 0; i < ttm->num_pages; ++i) {
 		(*page)->mapping = NULL;
 		(*page++)->index = 0;