https://bugzilla.kernel.org/show_bug.cgi?id=209159

Bug ID: 209159 Summary: AMD Vega 20 framebuffer switch fails on 5.9rc2+ Product: Drivers Version: 2.5 Kernel Version: 5.9-rc2/3 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: ryan@testtoast.com Regression: No

Created attachment 292349 --> https://bugzilla.kernel.org/attachment.cgi?id=292349&action=edit lspci

Vega 20 (Radeon VII) on X99 platform - boot freezes during FB switch. Booting without quiet and with earlyprintk=efi,keep shows a stall immediately after

... [ 1.941238] AMD-Vi: AMD IOMMUv2 driver by Joerg Roedel jroedel@suse.de [ 1.941239] AMD-Vi: AMD IOMMUv2 functionality not available on this system [ 1.948454] nvme nvme0: 20/0/0 default/read/poll queues [ 1.953176] nvme0n1: p1 p2 p3 p4 p5 p6 p7 [ 1.956313] usb 1-14: new full-speed USB device number 5 using xhci_hcd [ 1.989790] [drm] amdgpu kernel modesetting enabled. [ 1.989849] CRAT table not found [ 1.989850] Virtual CRAT table created for CPU [ 1.989857] amdgpu: Topology: Add CPU node [ 2.006244] checking generic (c0000000 300000) vs hw (c0000000 10000000) [ 2.006246] fb0: switching to amdgpudrmfb from EFI VGA

On -rc1 boot continues normally with ... [ 2.006315] amdgpu 0000:67:00.0: vgaarb: deactivate vga console [ 2.006345] amdgpu 0000:67:00.0: enabling device (0106 -> 0107) [ 2.006408] [drm] initializing kernel modesetting (VEGA20 0x1002:0x66AF 0x1002:0x081E 0xC1). ...