https://bugzilla.kernel.org/show_bug.cgi?id=194867
Bug ID: 194867 Summary: DRM BUG while initializing cape verde (2nd card) Product: Drivers Version: 2.5 Kernel Version: 4.11-rc2 Hardware: x86-64 OS: Linux Tree: Mainline Status: NEW Severity: normal Priority: P1 Component: Video(DRI - non Intel) Assignee: drivers_video-dri@kernel-bugs.osdl.org Reporter: janpieter.sollie@dommel.be Regression: No
Created attachment 255215 --> https://bugzilla.kernel.org/attachment.cgi?id=255215&action=edit zip file with all listed attachments
There seems to be a logical error while specifying the memory sizes for ttm in the amdgpu module on the SI architecture: while the Fiji card boots fine, the Cape Verde card gives a kernel BUG. dmesg and .config and proposed patch in attachment. the problem lies in linux/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c: the determination of the p_size is reduced 0 when the page_shift is too big I managed to work around the problem when changing the sentence "adev->gds.mem.total_size >> PAGE_SHIFT)" in amdgpu_ttm_init to "(adev->gds.mem.total_size >> PAGE_SHIFT) + 1)", and the same for "(adev->gds.gws.total_size" and "adev->gds.oa.total_size", though I am not sure this is the correct solution. The problem is that my SI card is limited in memory (I guess) and the page_size is 12