Created attachment 449880 [details] dmesg from failing v4.4.21 kernel When updating my stable gentoo-sources kernel from 4.4.6 to 4.4.21, I've noticed a regression on my desktop box. It has an ATI HD7660D card and, after using the very same .config file than for v4.4.6 ("make oldconfig", no changes whatsoever), the card is not properly initialised/recognized/whatever..., so I end up with a completely black screen. Reverting back to v4.4.6 solves the issue. I attach both dmesg cases. I use the radeon driver. The same updating procedure has worked (as expected) for my laptop, also with an ATI card (Radeon HD 6400M/7400M Series), and for another desktop box (old NVIDIA card with nouveau driver). Am I missing something or is it a legitimate regression?
Created attachment 449882 [details] dmesg from working v4.4.6 kernel
Created attachment 449884 [details] kernel .config file
From lspci: 00:01.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Trinity [Radeon HD 7660D]
Ever since the update to xorg 1.8. combined with recent kernel updates. I have been unable to get an ati card to work at all, it is a R9 390. Grub loads then black screen with kernel version 4.4.21. I am encountering problems with various kernel versions, combined with drivers, and other problems specific to package versions. Unable to find a combination of kernel version and driver and xorg version that all work together for an ati r9 390.
I do NOT use systemd, but openrc. Maybe this has something to do?
I found these pages by googling around. It seems a recognized problem with radeon cards that some people have been able to fix with this specific patch: https://github.com/torvalds/linux/commit/c8213a638f65bf487c10593c216525952cca3690 [drm:radeon_dp_link_train] *ERROR* clock recovery failed -bisected: https://lists.freedesktop.org/archives/dri-devel/2016-March/102222.html AMD APU via VGA gives blank screen: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1573648
Now this is getting "nice" :( gentoo-sources-4.4.6 is now removed from the tree due to a security bug, rendering my system unusable because this bug prevents me from seeing anything but a black screen. Why, *with the very same kernel .config file*, my radeon card in properly initialised with v4.4.6 but not with v4.4.26 if it weren't a kernel bug? From dmesg: =============== [ 10.520592] [drm:atom_op_jump [radeon]] *ERROR* atombios stuck in loop for more than 5secs aborting [ 10.520621] [drm:atom_execute_table_locked [radeon]] *ERROR* atombios stuck executing EC64 (len 2642, WS 0, PS 8) @ 0xF26C [ 10.566786] [drm:radeon_dp_link_train [radeon]] *ERROR* clock recovery reached max voltage [ 10.566820] [drm:radeon_dp_link_train [radeon]] *ERROR* clock recovery failed
(In reply to urcindalo from comment #7) > > Why, *with the very same kernel .config file*, my radeon card in properly > initialised with v4.4.6 but not with v4.4.26 if it weren't a kernel bug? "is properly"
OK, now I'm going nuts. After I had written the previous long message above (connected to the "black screen desktop box" through ssh from my laptop), I returned to my desktop (other room). To my surprise, the Plasma 5 login screen was visible! So, I logged in, checked out that I had booted with kernel 4.4.26, and rebooted to confirm that the screen needs a few minutes to appear (for whatever reason). However, after two reboots and waiting for more than 10 minutes each (much more time that I needed to write the messages above), the screen is still black. What's happening? Any idea?
Upgrading to ~gentoo-sources-4.8.4 with the .config file from v4.4.6, followed by a "make oldconfig" which asks for non-radeon-related questions, renders a working system. I finally get a visible screen with my Radeon HD 7660D card through my VGA connector. So, I think this shows there's something not right with the radeon code on the currently stable 4.4.26 version.
It's a shame Gentoo doesn't take masking unusable kernels seriously... There's issues with Intel DRM in the 4.4 branch too, honestly your best bet is to file a bug upstream if it isn't resolved. This LTS kernel is almost completely broken for gfx (can't speak to nouveau).
(In reply to Kyle Sanderson from comment #11) > It's a shame Gentoo doesn't take masking unusable kernels seriously... > > There's issues with Intel DRM in the 4.4 branch too, honestly your best bet > is to file a bug upstream if it isn't resolved. This LTS kernel is almost > completely broken for gfx (can't speak to nouveau). As I said in my opening message, nouveau does not seem to be affected, at least with my card (GeForce 8400 GS Rev. 2 through VGA), nor does the ATI card on my laptop (but, obviously, this latter card is not connected to the screen through a VGA connector). Right now ~gentoo-sources-4.8.4 seems to work correctly for me, so I'll keep it. I don't like to run ~core-system packages, but in this case I have no option and eventually it will be marked as stable ;) Have you tried it? kernel.org marks 4.8.4 as the latest stable version.
Original problem appears to be fixed per comments.
