On Wed, Oct 14, 2026 at 04:04:18PM -0700, Dave Hansen wrote: > I've got a custom kernel that has CONFIG_DRM_XE=y. I moved a disk from > an old NUC to a new Panther Lake one, and from it being SATA-attached to > USB-attached. > > The new system was hanging after GRUB: > > Loading Linux ... > Loading initial ramdisk ... > <nothing> > > Turns out, the root cause of the boot hang was my USB adapter needing a > rootdelay=15. But it took me a couple of hours, and a USB debug cable to > figure it out. Why? > > Because the xe driver was falling over itself and presumably sabotaging > the firmware framebuffer in the process: > > > [ 1.505387] xe 0000:00:02.0: vgaarb: deactivate vga console > > [ 1.507298] xe 0000:00:02.0: [drm] Running in SR-IOV PF mode > > [ 1.512831] xe 0000:00:02.0: [drm] Tile0: GT0: GuC firmware > > xe/ptl_guc_70.bin not found > > [ 1.512873] xe 0000:00:02.0: [drm] Tile0: GT0: GuC firmware(s) can be > > downloaded from > > https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git > > [ 1.512881] xe 0000:00:02.0: [drm] *ERROR* Tile0: GT0: Failed to > > initialize uC (-ENOENT) > > [ 1.512894] xe 0000:00:02.0: probe with driver xe failed with error -2 > > So instead of getting a nice message about my root disk problems, I just > got a hang after GRUB. Basically, missing XE firmware results in a > system which is undebuggable for normal humans*. > > There seem to have been similar issues in the past: > > > https://lore.kernel.org/lkml/[email protected]/
Cc: dri-devel Cc: Zack This definitely looks the right overall solution to the failed probe. So the VGA can be put back. > > Any chance that could be looked at again? This was a pretty insidious > failure mode. > > * Normal humans don't have USB debug cables lying around Agree. and mandatory FW or initramfs/initrd flows also don't help. So, perhaps what could be done in this specific case while we don't have the proper one is something like trying to pre-fetch the mandatory fw. Before we steal the fb. Something like: (Untested warning) https://github.com/rodrigovivi/linux/commit/5589d2883a604d52e89f44620e16d16c7fd278e8
