From e85424325911626556fbe5a313c698a5da701163 Mon Sep 17 00:00:00 2001 From: Peter Wu Date: Mon, 13 Aug 2018 22:59:50 +0200 Subject: [PATCH xf86-video-intel] SNA: fix PRIME output support since xserver 1.20 Since xorg-server 1.20, an external monitor would remain blank when used in a PRIME output slave setup. Only a cursor was visible. The cause is "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 will trigger a heap-buffer-overflow error due to to_sna_from_pixmap receiving a window instead of a pixmap. Test on a hybrid graphics laptop (Intel + modesetting/nouveau): xrandr --setprovideroutputsource modesetting Intel xrandr --output DP-1-1 --mode 2560x1440 # should not crash glxgears # should display gears on both screens Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=100086 Signed-off-by: Peter Wu --- Tested with xserver 1.20.1 with ASAN enabled. Survives multiple resolution changes, works with a Plasma desktop session, it seems stable. Something like this patch is required to make multi-monitor setups usable in a hybrid graphics setting with Xorg 1.20. --- src/sna/sna_accel.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/src/sna/sna_accel.c b/src/sna/sna_accel.c index 2f669bcf..80b116a3 100644 --- a/src/sna/sna_accel.c +++ b/src/sna/sna_accel.c @@ -17510,7 +17510,11 @@ static bool has_offload_slaves(struct sna *sna) PixmapDirtyUpdatePtr dirty; xorg_list_for_each_entry(dirty, &screen->pixmap_dirty_list, ent) { +#ifdef HAS_DIRTYTRACKING_DRAWABLE_SRC + assert(dirty->src == &sna->front->drawable); +#else assert(dirty->src == sna->front); +#endif if (RegionNotEmpty(DamageRegion(dirty->damage))) return true; } @@ -17671,7 +17675,11 @@ static void sna_accel_post_damage(struct sna *sna) if (RegionNil(damage)) continue; +#ifdef HAS_DIRTYTRACKING_DRAWABLE_SRC + src = get_drawable_pixmap(dirty->src); +#else src = dirty->src; +#endif dst = dirty->slave_dst->master_pixmap; region.extents.x1 = dirty->x; @@ -17922,9 +17930,15 @@ migrate_dirty_tracking(PixmapPtr old_front, PixmapPtr new_front) PixmapDirtyUpdatePtr dirty, safe; xorg_list_for_each_entry_safe(dirty, safe, &screen->pixmap_dirty_list, ent) { +#ifdef HAS_DIRTYTRACKING_DRAWABLE_SRC + assert(dirty->src == &old_front->drawable); + if (dirty->src != &old_front->drawable) + continue; +#else assert(dirty->src == old_front); if (dirty->src != old_front) continue; +#endif DamageUnregister(&dirty->src->drawable, dirty->damage); DamageDestroy(dirty->damage); @@ -17939,7 +17953,11 @@ migrate_dirty_tracking(PixmapPtr old_front, PixmapPtr new_front) } DamageRegister(&new_front->drawable, dirty->damage); +#ifdef HAS_DIRTYTRACKING_DRAWABLE_SRC + dirty->src = &new_front->drawable; +#else dirty->src = new_front; +#endif } #endif } -- 2.18.0