sna/dri2: Prevent the sw cursor from copyig to a buffer as we discard it

During swapbuffers, the sw cursor tries to write to the old buffer.
Ordinary this is not an issue as we are discarding it, but under
TearFree that write causes us to instantiate the shadow buffer with a
possible recursion into set_bo and mayhem.

v2:

commit 226a58bc592d4ed305b7ad0e460f1ee2548e0ddf
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Sat Apr 4 20:58:24 2015 +0100

    sna/dri2: Prevent the sw cursor from copyig to a buffer as we discard it

Tried to fix it by disabling SourceValidate. However, it a direct hook
into the Damage code by miSprite that triggers the copy. Since there
appears to be no way to intervene, we just mark that copy as internal
and ignore it.

Reported-by: Chris Bainbridge <chris.bainbridge@gmail.com>
References: https://bugs.freedesktop.org/show_bug.cgi?id=89903
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 2 insertions, 0 deletions

diff --git a/src/sna/sna.h b/src/sna/sna.h
index a4984849..51533995 100644
--- a/src/sna/sna.h
+++ b/src/sna/sna.h
@@ -265,6 +265,8 @@ struct sna {
 #define AVX 0x80
 #define AVX2 0x100
 
+	bool ignore_copy_area : 1;
+
 	unsigned watch_flush;
 
 	struct timeval timer_tv;