View source for Services/ArcB580Driver

''As of: 2026-07-05 — migrated from `services/ARC-B580-DRIVER.md`''

= Intel Arc B580 (Battlemage) — xe Driver Notes =

== Problem ==

The <code>xe</code> kernel driver for the Arc B580 crashes the system when the monitor is switched
off/on manually. Root cause: the driver uses aggressive display power-saving states (DC states)
that fail to wake properly on Battlemage, causing a cascade of GPU timeouts that brings
the system down.

Symptoms in logs:
'' <code>xe 0000:0b:00.0: [drm] ''ERROR* Tile0: GT1: Force wake domain X failed to ack wake (-ETIMEDOUT)</code>
* <code>xe 0000:0b:00.0: [drm] Tile0: GT1: trying reset from guc_exec_queue_timedout_job</code>
'' <code>xe 0000:0b:00.0: [drm] ''ERROR* PCODE Mailbox failed: 1 Illegal Command</code>
* UBSAN: array-index-out-of-bounds in <code>mtd_intel_dg.c</code>

== Fix Applied (2026-05-03) ==

'''File 1: <code>/etc/modprobe.d/xe-options.conf</code>'''
<syntaxhighlight lang="text">
options xe enable_dc=0
</syntaxhighlight>
Disables aggressive display C-states so the driver doesn't enter a deep sleep it can't
wake from when the monitor is switched off.

'''File 2: <code>/etc/modprobe.d/blacklist.conf</code>''' (appended)
<syntaxhighlight lang="text">
blacklist mtd_intel_dg
</syntaxhighlight>
Blacklists the <code>mtd_intel_dg</code> module which has a confirmed kernel UBSAN bug on this GPU.

Both changes require initramfs rebuild + reboot to take effect.

----

== How to Revert (if the fix breaks boot) ==

SSH in from another host, then:

<syntaxhighlight lang="bash">
# 1. Remove the xe options file
sudo rm /etc/modprobe.d/xe-options.conf

# 2. Remove the two lines added to blacklist.conf
#    (the blank line, comment, and blacklist entry at the bottom)
sudo nano /etc/modprobe.d/blacklist.conf
# Delete the last 3 lines:
#   (blank line)
#   # Intel Arc B580 - mtd_intel_dg has a confirmed kernel UBSAN bug (array out-of-bounds)
#   blacklist mtd_intel_dg

# 3. Rebuild initramfs
sudo update-initramfs -u

# 4. Reboot
sudo reboot
</syntaxhighlight>

Or as a one-liner if you want to skip the editor:

<syntaxhighlight lang="bash">
sudo rm /etc/modprobe.d/xe-options.conf && \
sudo head -n -3 /etc/modprobe.d/blacklist.conf | sudo tee /etc/modprobe.d/blacklist.conf.tmp && \
sudo mv /etc/modprobe.d/blacklist.conf.tmp /etc/modprobe.d/blacklist.conf && \
sudo update-initramfs -u && \
sudo reboot
</syntaxhighlight>

----

== If you need to go back to the Radeon ==

# Power off, swap GPU physically
# SSH in (or boot to TTY) and blacklist xe so it doesn't try to load for a missing device:
   ```bash
   echo "blacklist xe" | sudo tee /etc/modprobe.d/blacklist-xe.conf
   sudo update-initramfs -u
   sudo reboot
   ```
# The <code>radeon</code> or <code>amdgpu</code> driver will load automatically depending on which card.

----

== Kernel / Firmware versions at time of fix ==

* Kernel: <code>6.18.1-061801-generic</code>
* GuC firmware: <code>xe/bmg_guc_70.bin</code> version <code>70.60.0</code>
* HuC firmware: <code>xe/bmg_huc.bin</code> version <code>8.2.10</code>
* DMC firmware: <code>i915/bmg_dmc.bin</code> version <code>2.6</code>

If you upgrade the kernel and the crashes stop, the fix may no longer be needed — test by
removing <code>xe-options.conf</code> after a kernel upgrade to see if stability holds without it.