Duncan posted on Mon, 16 Aug 2021 07:58:37 +0000 as excerpted:
Mikael Pettersson posted on Tue, 03 Aug 2021 08:54:18 +0200 as excerpted:
On Mon, Aug 2, 2021 at 8:29 PM Duncan j.duncan@cox.net wrote:
Mikael Pettersson mikpelinux@gmail.com wrote...
Booting 5.14.0-rc4 on my box with Radeon graphics breaks with
[drm:radeon_ttm_init [radeon]] *ERROR* failed initializing buffer object driver(-19). radeon 0000:01:00.0: Fatal error during GPU init
Seeing this here too. amdgpu on polaris-11, on an old amd-fx6100 system.
after which the screen goes black for the rest of kernel boot and early user-space init.
*NOT* seeing that. However, I have boot messages turned on by default and I see them as usual, only it stays in vga-console mode instead of switching to framebuffer after early-boot. I'm guessing MP has a high-res boot-splash which doesn't work in vga mode, thus the black-screen until the login shows up.
Yes, I have the Fedora boot splash enabled.
Once the console login shows up the screen is in some legacy low-res mode and Xorg can't be started.
A git bisect between v5.14-rc3 (good) and v5.14-rc4 (bad) identified
# first bad commit: [69de4421bb4c103ef42a32bafc596e23918c106f] drm/ttm: Initialize debugfs from ttm_global_init()
Reverting that from 5.14.0-rc4 gives me a working kernel again.
Note that I have # CONFIG_DEBUG_FS is not set
That all matches here, including the unset CONFIG_DEBUG_FS and confirming the revert on 5.14.0-rc4 works.
Thanks for the confirmation.
69de44d1bb introduced a regression in rc4, reported to the list on August 2, that's still there in rc6. It's also reported on kernel bugzilla as bug #214000. No maintainer response either on-list or to the bug. The commit was general ttm and the original post went to dri-devel and kernel, Jason E. and Daniel V., but all three user reports I've seen so far (two on-list and the bug reporter) are on amdgpu or radeon, so in an effort to at least get a response and hopefully a fix before release, I'm adding the amdgpu/radeon list and maintainers.
The bugzilla report confirmed that CONFIG_DEBUG_FS=y AND CONFIG_DEBUG_FS_ALLOW_ALL=y were *both* required to get a working kernel after that commit. I and I believe the on-list reporter just reverted the commit in question, and kept our CONFIG_DEBUG_FS=n.
Trying again. I apologize if anyone gets this twice but I don't think the first one made it at all (buggy client).