drm/radeon: Override fpfn for all VRAM placements in radeon_evict_flags

BugLink: http://bugs.launchpad.net/bugs/1681875
commit ce4b4f228e51219b0b79588caf73225b08b5b779 upstream.

We were accidentally only overriding the first VRAM placement. For BOs
with the RADEON_GEM_NO_CPU_ACCESS flag set,
radeon_ttm_placement_from_domain creates a second VRAM placment with
fpfn == 0. If VRAM is almost full, the first VRAM placement with
fpfn > 0 may not work, but the second one with fpfn == 0 always will
(the BO's current location trivially satisfies it). Because "moving"
the BO to its current location puts it back on the LRU list, this
results in an infinite loop.

Fixes: 2a85aedd117c ("drm/radeon: Try evicting from CPU accessible to
                      inaccessible VRAM first")
Reported-by: Zachary Michaels <zmichaels@oblong.com>
Reported-and-Tested-by: Julien Isorce <jisorce@oblong.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c b/drivers/gpu/drm/radeon/radeon_ttm.c
index 0cf03ccbf0a72521f3d80d38d2e0ba7b4d4ba6de..445a907552c13cc5a4db286338590fca324076be 100644 (file)
--- a/drivers/gpu/drm/radeon/radeon_ttm.c
+++ b/drivers/gpu/drm/radeon/radeon_ttm.c
@@ -213,8 +213,8 @@ static void radeon_evict_flags(struct ttm_buffer_object *bo,
                        rbo->placement.num_busy_placement = 0;
                        for (i = 0; i < rbo->placement.num_placement; i++) {
                                if (rbo->placements[i].flags & TTM_PL_FLAG_VRAM) {
-                                       if (rbo->placements[0].fpfn < fpfn)
-                                               rbo->placements[0].fpfn = fpfn;
+                                       if (rbo->placements[i].fpfn < fpfn)
+                                               rbo->placements[i].fpfn = fpfn;
                                } else {
                                        rbo->placement.busy_placement =
                                                &rbo->placements[i];