On Fri, 15 Apr 2022, Stefan de Konink via Cin wrote:
/dev/dri/card0 sometimes becomes /dev/dri/card1. Maybe a more stable identified something like 'by path' would help software in general, so the choice can be actually set to 'a card' rather than 'a number'.
I personally never had a system with several videocards enabled simultaneously, but perhaps the uncertainty in the order they are enumerated by the kernel could be solved in a similar manner as for other types of devices. Here are several recipes I used elsewhere. 1) /etc/modprobe.d/usb-controller.conf This ensures loading the ehci USB driver before uhci and ohci: softdep uhci-hcd pre: ehci-hcd softdep ohci-hcd pre: ehci-hcd 2) a rule in /etc/udev/rules.d which defines the enumeration order of two different audio devices (one was RTL HDAudio chip on the motherboard, the other HDMI output on the ATI graphic card): SUBSYSTEM!="sound", GOTO="my_usb_audio_end" ACTION!="add", GOTO="my_usb_audio_end" DEVPATH=="/devices/pci0000:00/0000:00:03.0/sound/card?", ATTR{index}=1 DEVPATH=="/devices/pci0000:00/0000:00:1b.0/sound/card?", ATTR{index}=0 LABEL="my_usb_audio_end" 3) another method in /etc/modprobe.d which corrects enumeration of two audio devices, both controlled by the same snd_hda_intel driver (one is HDAudio on motherboard, the other HDMI output of the on-chip Intel graphics): # Reverse HDA Intel cards ordering: options snd_hda_intel index="1,0" _______________________________________________________________________________ Georgy Salnikov NMR Group Novosibirsk Institute of Organic Chemistry Lavrentjeva, 9, 630090 Novosibirsk, Russia Phone +7-383-3307864 Email [email protected] _______________________________________________________________________________