Commits
![Michael D Labriola](https://secure.gravatar.com/avatar/903a997635e618b9438176ecaaa79546.jpg?s=96&d=mm)
Michael D Labriola committed 913b2cb727b
drm: change func to better detect wether swiotlb is needed This commit fixes DRM failures on Xen PV systems that were introduced in v4.17 by the following commits: 82626363 drm: add func to get max iomem address v2 fd5fd480 drm/amdgpu: only enable swiotlb alloc when need v2 1bc3d3cc drm/radeon: only enable swiotlb path when need v2 The introduction of ->need_swiotlb to the ttm_dma_populate() conditionals in the radeon and amdgpu device drivers causes Gnome to immediately crash on Xen PV systems, returning the user to the login screen. The following kernel errors get logged: [ 28.554259] radeon_dp_aux_transfer_native: 200 callbacks suppressed [ 31.219821] radeon 0000:01:00.0: swiotlb buffer is full (sz: 2097152 bytes) [ 31.220030] [drm:radeon_gem_object_create [radeon]] *ERROR* Failed to allocate GEM object (16384000, 2, 4096, -14) [ 31.226109] radeon 0000:01:00.0: swiotlb buffer is full (sz: 2097152 bytes) [ 31.226300] [drm:radeon_gem_object_create [radeon]] *ERROR* Failed to allocate GEM object (16384000, 2, 4096, -14) [ 31.300734] gnome-shell[1935]: segfault at 88 ip 00007f39151cd904 sp 00007ffc97611ad8 error 4 in libmutter-cogl.so[7f3915178000+aa000] [ 31.300745] Code: 5f c3 0f 1f 40 00 48 8b 47 78 48 8b 40 40 ff e0 66 0f 1f 44 00 00 48 8b 47 78 48 8b 40 48 ff e0 66 0f 1f 44 00 00 48 8b 47 78 <48> 8b 80 88 00 00 00 ff e0 0f 1f 00 48 8b 47 78 48 8b 40 68 ff e0 [ 38.193302] radeon_dp_aux_transfer_native: 116 callbacks suppressed [ 40.009317] radeon 0000:01:00.0: swiotlb buffer is full (sz: 2097152 bytes) [ 40.009488] [drm:radeon_gem_object_create [radeon]] *ERROR* Failed to allocate GEM object (16384000, 2, 4096, -14) [ 40.015114] radeon 0000:01:00.0: swiotlb buffer is full (sz: 2097152 bytes) [ 40.015297] [drm:radeon_gem_object_create [radeon]] *ERROR* Failed to allocate GEM object (16384000, 2, 4096, -14) [ 40.028302] gnome-shell[2431]: segfault at 2dadf40 ip 0000000002dadf40 sp 00007ffcd24ea5f8 error 15 [ 40.028306] Code: 20 6e 31 00 00 00 00 00 00 00 00 37 e3 3d 2d 7f 00 00 80 f4 e6 3d 2d 7f 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 <00> 00 00 00 00 00 00 00 c1 00 00 00 00 00 00 00 80 e1 d2 03 00 00 This commit renames drm_get_max_iomem() to drm_need_swiotlb(), adds a xen_pv_domain() check to it, and moves the bit shifting comparison that always follows its usage into the function (simplifying the drm driver code). Signed-off-by: Michael D Labriola <michael.d.labriola@gmail.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Christian König <christian.koenig@amd.com> Link: https://patchwork.freedesktop.org/patch/286987/