drm/radeon/kms: fix potential segfault in r600_ioctl_wait_idle
radeon_gem_wait_idle_ioctl can apparently get called prior to
the vram page being set up or even if accel if false, so make
sure it's valid before using it.
Should fix:
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=597636
https://bugs.freedesktop.org/show_bug.cgi?id=29834
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c
index ddc3ade..7a04959 100644
--- a/drivers/gpu/drm/radeon/r600.c
+++ b/drivers/gpu/drm/radeon/r600.c
@@ -3528,7 +3528,8 @@
/* r7xx hw bug. write to HDP_DEBUG1 followed by fb read
* rather than write to HDP_REG_COHERENCY_FLUSH_CNTL
*/
- if ((rdev->family >= CHIP_RV770) && (rdev->family <= CHIP_RV740)) {
+ if ((rdev->family >= CHIP_RV770) && (rdev->family <= CHIP_RV740) &&
+ rdev->vram_scratch.ptr) {
void __iomem *ptr = (void *)rdev->vram_scratch.ptr;
u32 tmp;
