[Intel-gfx] [PATCH xf86-video-intel v2] SNA: fix PRIME output support since xserver 1.20

[Peter Wu]

On Fri, Nov 15, 2019 at 08:14:05PM +0200, Ville Syrjälä wrote:
> On Fri, Nov 15, 2019 at 04:32:47PM +0100, Peter Wu wrote:
> > Since "Make PixmapDirtyUpdateRec::src a DrawablePtr" in xserver, the
> > "src" pointer might point to the root window (created by the server)
> > instead of a pixmap (as created by xf86-video-intel). Use
> > get_drawable_pixmap to handle both cases.
> > 
> > When built with -fsanitize=address, the following test on a hybrid
> > graphics laptop will trigger a heap-buffer-overflow error due to
> > to_sna_from_pixmap receiving a window instead of a pixmap:
> > 
> >     xrandr --setprovideroutputsource modesetting Intel
> >     xrandr --output DP-1-1 --mode 2560x1440  # should not crash
> >     glxgears  # should display gears on both screens
> > 
> > With nouveau instead of modesetting, it does not crash but the external
> > monitor remains blank aside from a mouse cursor. This patch fixes both.
> > 
> > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=100086
> 
> Also
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111976

I marked this bug as duplicate of the former since it is the same issue.

About the CI failure
(https://lists.freedesktop.org/archives/intel-gfx/2019-November/220187.html),
should I be concerned? I can't see what tree it is trying to apply the
patch to. Is it actually trying to apply it to xf86-video-intel, or is
it trying the Linux kernel instead?

> > Signed-off-by: Peter Wu <peter at lekensteyn.nl>
> > ---
> > v1: https://lists.freedesktop.org/archives/intel-gfx/2018-August/173522.html
> > v2: rebased on current master (2.99.917-893-gbff5eca4), reworded commit.
> > 
> > This patch has been tested at https://bugs.archlinux.org/task/64238, I
> > have additionally tested it with both modesetting and nouveau under
> > ASAN, the modesetting ASAN trace for unpatched intel can be found at:
> > https://bugs.freedesktop.org/show_bug.cgi?id=100086#c24
> > 
> > commit 2.99.917-891-g581ddc5d ("sna: Fix compiler warnings due to
> > DrawablePtr vs. PixmapPtr") incorporated all compiler warning fixes from
> > v1 of this patch, but unfortunately lacks this crucial bugfix.
> > ---
> >  src/sna/sna_accel.c | 6 +++---
> >  1 file changed, 3 insertions(+), 3 deletions(-)
> > 
> > diff --git a/src/sna/sna_accel.c b/src/sna/sna_accel.c
> > index fa386ff6..ee857a14 100644
> > --- a/src/sna/sna_accel.c
> > +++ b/src/sna/sna_accel.c
> > @@ -17684,10 +17684,10 @@ static void sna_accel_post_damage(struct sna *sna)
> >  			continue;
> >  
> >  #ifdef HAS_DIRTYTRACKING_DRAWABLE_SRC
> > -		assert(dirty->src->type == DRAWABLE_PIXMAP);
> > +		src = get_drawable_pixmap(dirty->src);
> > +#else
> > +		src = dirty->src;
> >  #endif
> > -
> > -		src = (PixmapPtr)dirty->src;
> >  		dst = dirty->slave_dst->master_pixmap;
> >  
> >  		region.extents.x1 = dirty->x;
> > -- 
> > 2.23.0
> 
> -- 
> Ville Syrjälä
> Intel