Michael Cree and I have been debugging FDO bug 26403 [1]. I tried booting with `radeon.test=1` and found this, which I think is related:
[drm] Tested GTT->VRAM and VRAM->GTT copy for GTT offset 0x202000 [drm] Tested GTT->VRAM and VRAM->GTT copy for GTT offset 0x302000
[snip]
[drm] Tested GTT->VRAM and VRAM->GTT copy for GTT offset 0xfd02000 [drm] Tested GTT->VRAM and VRAM->GTT copy for GTT offset 0xfe02000 pci_map_single failed: could not allocate dma page tables [drm:radeon_ttm_backend_bind] *ERROR* failed to bind 128 pages at 0x0FF02000 [TTM] Couldn't bind backend. radeon 0000:00:07.0: object_init failed for (1048576, 0x00000002) [drm:radeon_test_moves] *ERROR* Failed to create GTT object 253 Error while testing BO move.
From what I can see, the call chain is
radeon_test_moves (radeon_ttm_backend_bind called through callback function) - radeon_ttm.c:radeon_ttm_backend_bind calls radeon_gart_bind - radeon_gart.c:radeon_gart_bind calls pci_map_page - pci_map_page is alpha_pci_map_page, which calls... - alpha_pci_map_page calls pci_iommu.c:pci_map_single_1 - pci_map_single_1 calls iommu_arena_alloc - iommu_arena_alloc calls iommu_arena_find_pages - iommu_arena_find_pages returns non-0 - iommu_arena_alloc returns non-0 - pci_map_single_1 returns 0 after printing "could not allocate dma page tables" error - alpha_pci_map_page returns 0 from pci_map_single_1 - radeon_gart_bind returns non-0, error path prints "*ERROR* failed to bind 128 pages at 0x0FF02000"
Is this the cause of the bug we're seeing in the report [1]?
Anyone know what's going wrong here?
Thanks! Matt Turner