diff options
authorDave Airlie <airlied@gmail.com>2013-01-16 14:25:44 +1000
committerDave Airlie <airlied@redhat.com>2013-01-21 13:45:02 +1000
commit630541863b29f88c7ab34e647758344e4cd1eafd (patch)
parentffb5fd53ef27df22a6850019ecb5488686a573f1 (diff)
ttm: don't destroy old mm_node on memcpy failure
When we are using memcpy to move objects around, and we fail to memcpy due to lack of memory to populate or failure to finish the copy, we don't want to destroy the mm_node that has been copied into old_copy. While working on a new kms driver that uses memcpy, if I overallocated bo's up to the memory limits, and eviction failed, then machine would oops soon after due to having an active bo with an already freed drm_mm embedded in it, freeing it a second time didn't end well. Reviewed-by: Jerome Glisse <jglisse@redhat.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
1 files changed, 9 insertions, 2 deletions
diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c
index d73d6e3e17b..44420fca7df 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_util.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
@@ -344,8 +344,12 @@ int ttm_bo_move_memcpy(struct ttm_buffer_object *bo,
if (ttm->state == tt_unpopulated) {
ret = ttm->bdev->driver->ttm_tt_populate(ttm);
- if (ret)
+ if (ret) {
+ /* if we fail here don't nuke the mm node
+ * as the bo still owns it */
+ old_copy.mm_node = NULL;
goto out1;
+ }
add = 0;
@@ -371,8 +375,11 @@ int ttm_bo_move_memcpy(struct ttm_buffer_object *bo,
} else
ret = ttm_copy_io_page(new_iomap, old_iomap, page);
- if (ret)
+ if (ret) {
+ /* failing here, means keep old copy as-is */
+ old_copy.mm_node = NULL;
goto out1;
+ }