From a06b9a74c73750835b8fd69fe0d0bd7877da111b Mon Sep 17 00:00:00 2001
From: Maarten Lankhorst <m.b.lankhorst@gmail.com>
Date: Thu, 27 Jun 2013 13:38:25 +0200
Subject: [PATCH] drm/mgag200: do not attempt to acquire a reservation while in
an interrupt handler
Mutexes should not be acquired in interrupt context. While the trylock
fastpath is arguably safe on all implementations, the slowpath
unlock path definitely isn't.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
---
drivers/gpu/drm/mgag200/mgag200_fb.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/mgag200/mgag200_fb.c b/drivers/gpu/drm/mgag200/mgag200_fb.c
index 5da824ce9ba13..964f58cee5ea6 100644
--- a/drivers/gpu/drm/mgag200/mgag200_fb.c
+++ b/drivers/gpu/drm/mgag200/mgag200_fb.c
@@ -27,7 +27,7 @@ static void mga_dirty_update(struct mga_fbdev *mfbdev,
struct mgag200_bo *bo;
int src_offset, dst_offset;
int bpp = (mfbdev->mfb.base.bits_per_pixel + 7)/8;
- int ret;
+ int ret = -EBUSY;
bool unmap = false;
bool store_for_later = false;
int x2, y2;
@@ -41,7 +41,8 @@ static void mga_dirty_update(struct mga_fbdev *mfbdev,
* then the BO is being moved and we should
* store up the damage until later.
*/
- ret = mgag200_bo_reserve(bo, true);
+ if (!in_interrupt())
+ ret = mgag200_bo_reserve(bo, true);
if (ret) {
if (ret != -EBUSY)
return;