Bug 278363 - linsysfs: /sys/class/drm and /sys/dev/char/226:* contents don't match /dev/dri
Summary: linsysfs: /sys/class/drm and /sys/dev/char/226:* contents don't match /dev/dri
Status: New
Alias: None
Product: Base System
Classification: Unclassified
Component: kern (show other bugs)
Version: Unspecified
Hardware: Any Any
: --- Affects Only Me
Assignee: freebsd-emulation (Nobody)
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2024-04-14 15:27 UTC by Alex S
Modified: 2024-04-15 16:24 UTC (History)
1 user (show)

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Description Alex S 2024-04-14 15:27:07 UTC 
There are two significant issues here:

1. linsysfs creates entries for everything that has vgapci attached to it, regardless of whether the GPU has any associated /dev/dri/card* nodes — this might (and occasionally does) result in Mesa's libGL picking the wrong driver in multi-GPU configurations;

2. there are no entries for /dev/dri/renderD* nodes, which breaks Vulkan initialization, forcing Mesa to choose the software rendering fallback.

(See https://github.com/freebsd/drm-kmod/issues/290 and https://forums.freebsd.org/threads/linuxulator-vs-intel-amd-gpus.92445/ for context.)