On 26/09/16 09:09 PM, Takashi Iwai wrote: > On Mon, 26 Sep 2016 11:42:16 +0200, Takashi Iwai wrote: >> On Mon, 26 Sep 2016 10:57:50 +0200, Michel D4nzer wrote: >>> On 23/09/16 10:06 PM, Takashi Iwai wrote: >>>> radeon_cursor_move_unlock() contains a workaround for AVIVO chips that >>>> are older than DCE6 when the cursor ends on 128 pixel boundary. It >>>> decreases the position when the calculated end position is on 128 >>>> pixel boundary. However, it hits also the condition where x=-1 and >>>> width=1 are passed, since cursor_end is 0 (which is aligned with 128, >>>> too). Then the value gets decreased and it hits WARN_ON_ONCE() >>>> below, eventually screws up the GPU. >>>> >>>> The fix is simply to skip the workaround when x is already zero. >>>> Also, remove the superfluous WARN_ON_ON() for the negative value check >>>> that wouldn't happen any longer after this change. >>>> >>>> Bugzilla: https://bugzilla.suse.com/show_bug.cgi?id=1000433 >>>> Cc: <stable@xxxxxxxxxxxxxxx> >>>> Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> >>>> --- >>>> drivers/gpu/drm/radeon/radeon_cursor.c | 4 +--- >>>> 1 file changed, 1 insertion(+), 3 deletions(-) >>>> >>>> diff --git a/drivers/gpu/drm/radeon/radeon_cursor.c b/drivers/gpu/drm/radeon/radeon_cursor.c >>>> index 2a10e24b34b1..4e436eb49a56 100644 >>>> --- a/drivers/gpu/drm/radeon/radeon_cursor.c >>>> +++ b/drivers/gpu/drm/radeon/radeon_cursor.c >>>> @@ -193,10 +193,8 @@ static int radeon_cursor_move_locked(struct drm_crtc *crtc, int x, int y) >>>> if (w <= 0) { >>>> w = 1; >>>> cursor_end = x - xorigin + w; >>>> - if (!(cursor_end & 0x7f)) { >>>> + if (x > 0 && !(cursor_end & 0x7f)) >>>> x--; >>>> - WARN_ON_ONCE(x < 0); >>>> - } >>>> } >>> >>> The problem with this change is that the horizontal cursor end position >>> can again and up as a multiple of 128, which this code is trying to >>> avoid, because it can break the cursor with some versions of AVIVO / DCE >>> display engines. >>> >>> Attached is a proof-of-concept (only compile tested) alternative fix >>> which hides the cursor while it's out of bounds. I'll test it, clean it >>> up and split it up into multiple patches when I get a chance, but maybe >>> you or the reporter of the referenced bug can test it in the meantime. >> >> Sure, I'll ask the reporter to test with your tentative fix. > > Through a quick test by Tomas (added to Cc), the new patch seems > working. Thanks for testing, Tomáš! I sent an updated patch series to the amd-gfx mailing list and put you guys in Cc. -- Earthling Michel Dänzer | http://www.amd.com Libre software enthusiast | Mesa and X developer _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
