Created attachment 295741 [details] lspci -vvv On linux v5.11 and above (up to 5.11.4) I cannot longer boot the system (GNOME/Wayland) using two graphics cards. It gets stuck with black screen with no response to keyboard/mouse. In systemd journal there are some messages about kernel bug: Mar 08 11:54:05 homeserver kernel: BUG: kernel NULL pointer dereference, address: 0000000000000008 Mar 08 11:54:05 homeserver kernel: #PF: supervisor read access in kernel mode Mar 08 11:54:05 homeserver kernel: #PF: error_code(0x0000) - not-present page Mar 08 11:54:05 homeserver kernel: PGD 0 P4D 0 Mar 08 11:54:05 homeserver kernel: Oops: 0000 [#1] PREEMPT SMP NOPTI Mar 08 11:54:05 homeserver kernel: CPU: 6 PID: 608 Comm: gnome-shell Tainted: G OE 5.11.4-arch1-1 #1 Mar 08 11:54:05 homeserver kernel: Hardware name: Gigabyte Technology Co., Ltd. A320M-S2H/A320M-S2H-CF, BIOS F2 11/03/2020 Mar 08 11:54:05 homeserver kernel: RIP: 0010:drm_gem_handle_create_tail+0xcb/0x190 [drm] Mar 08 11:54:05 homeserver kernel: Code: 00 48 89 df e8 c6 20 59 f4 45 85 e4 78 77 48 8d 5d 18 4c 89 ee 48 89 df e8 42 fe 00 00 89 c2 85 c0 75 3e 48 8b 85 40 01 00 00 <48> 8b 40 08 48 85 c0 74 0f 4c 89 ee 48 89 ef e8 81 8b 91 f4 85 c0 Mar 08 11:54:05 homeserver kernel: RSP: 0018:ffffb7a7c16bfd30 EFLAGS: 00010246 Mar 08 11:54:05 homeserver kernel: RAX: 0000000000000000 RBX: ffffa0eabe065090 RCX: 0000000000000001 Everything works perfectly fine using current LTS v5.10.21. I am using Radeon RX 470 as a primary card, and the older ATI FirePro 2270 as a secondary one in order to provide two extra monitor outputs. I've attached my lspci output as well as full systemd log.
Created attachment 295743 [details] systemd journal
Likely the same issue as this: https://www.spinics.net/lists/amd-gfx/msg59207.html
Should be fixed with this patch: https://patchwork.freedesktop.org/patch/423250/
I can confirm now that the issue is fixed in recent 5.11.7 kernel.