Arch Linux

ConfusedInConsett

Member

Registered: 2020-05-14

Posts: 5

[SOLVED] Screen goes blank during boot

Firstly, sorry if this is in the wrong place/wrong format/wrong plane of reality. I've been using Arch for a few years but this is my first foray into forums.

I'm currently dual-booting with Windows (distasteful, I know, but I need Excel and Adobe). Everything was happily coexisting (all booting in EFI mode, the civil war over system time resolved, hardware all happy in Arch, etc.) until today, when my attempt to boot into Arch was met with a blank screen. I tried again in verbose, and it showed that everything was going fine, got as far as loading GDM and Network Manager ([OK]), then... went blank, with a little pulse of the CPU fan.

"Aha!" says I. "Display manager problems! Must have been an upgrade." But I couldn't change tty to get into the system, just that blank screen. Bafflingly, the same problem arose when I tried to boot from an Arch live USB intending to chroot in: boot hangs on a blank screen with no warning once again (and again, with a tiny puff of protest from the CPU cooler). Not the display manager, then. After trying live CDs from various other linux distros with the same result, reflashing the bios, disconnecting all drives (and with my Windows boot still mocking me by working perfectly normally all the while), I admitted defeat and came here.

Sorry I can't post the relevant log files, but since I can boot into exactly no linux right now, they're tricky to get at. My hardware is:

Intel i5-4430
Gigabyte Z87-HD3
AMD Radeon RX 580
16GB RAM

I know it's not exactly Arch related, but if anyone has any idea what is going on here, it'd be very gratefully received. I've not got a great deal to go on, sadly, so diagnosis isn't straightforward.

Last edited by ConfusedInConsett (2020-05-14 16:43:50)

ConfusedInConsett

Member

Registered: 2020-05-14

Posts: 5

Re: [SOLVED] Screen goes blank during boot

I have a new potential clue. Trying to boot the Arch live USB from rEFInd, I get the following kernel panic message

0.076952 [Firmware Bug]: TSC_DEADLINE disabled due to Errata; please update microcode to version: 0x22 (or later)
1.028250 Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)
1.028351 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.6.8-arch1-1 #1
1.028426 Hardware name: Gigabyte Technology Co., Ltd. Z87-HD3/Z87-HD3, BIOS F8 08/12/2014
1.028...    Call Trace:
1.028...      dump_stack+0x66/0x90
1.028...      panic_0x122/0x2e8
1.028...      mount_block_root+0x31c/0x32b
1.028...      ? rest_init+0xbf/0xbf
1.028...      prepare_namespace+0x136/0x165
1.028...      ? rest_init+0xbf/0xbf
1.028...      kernel_init+0xa/0x101
1.028...      ret_from_fork+0x35/0x40
1.028...    Kernel Offset: 0x2bc00000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
1.029...    ---[ end Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) ]---

Booting via the bootloader installed on the live USB gives a perfectly functional startup with no error messages, until it all goes blank part way through as described in the initial message.

I am unfortunately too stupid to understand what this means (beyond the basic "Der Computer ist kaputt") and my cursory googling so far has drawn something of a blank. Wisdom gladly welcomed.

Last edited by ConfusedInConsett (2020-05-14 12:12:06)

ConfusedInConsett

Member

Registered: 2020-05-14

Posts: 5

Re: [SOLVED] Screen goes blank during boot

So it transpires that the problem is solely with the graphics. The system is booting fine, but the picture cuts out when amdgpu takes over. Looking in the logs, I seem to have a new error during boot:

amdgpu 0000:01:00.0: [drm] Cannot find any crtc or sizes

The solution was to append

amdgpu.dc=0

to the kernel parameters. Which is annoyingly easy for a problem that took me several hours to diagnose and repair. May my cluelessness be to the benefit of some other frustrated user in future.

(Solved)

Last edited by ConfusedInConsett (2020-05-14 16:43:00)

Lone_Wolf

Administrator

From: Netherlands, Europe

Registered: 2005-10-04

Posts: 13,031

Re: [SOLVED] Screen goes blank during boot

amdgpu.dc=0 severely limits the functionality of your videocard, for a well supported card like RX 580 it should never be needed.

Does windows OS show problems ?

You should also check https://wiki.archlinux.org/index.php/Du … th_Windows

---

Disliking systemd intensely, but not satisfied with alternatives so focusing on taming systemd.

clean chroot building not flexible enough ?
Try clean chroot manager by graysky

ConfusedInConsett

Member

Registered: 2020-05-14

Posts: 5

Re: [SOLVED] Screen goes blank during boot

amdgpu.dc=0 severely limits the functionality of your videocard, for a well supported card like RX 580 it should never be needed.

Does windows OS show problems ?

You should also check https://wiki.archlinux.org/index.php/Du … th_Windows

It is a bizarre bug, I grant you, although one that seems to occur frequently enough with the RX 470/480/570/580 cards to have several reports online.
Windows is behaving itself fine; I tried some panorama stitching, a spot of rendering and a bit of gaming to see if I could perceive or record any quality degradation and everything seems much as before speed/temp/framerate-wise (i.e. my CPU continues to bottleneck the GPU as ever!). It's correctly identifying the monitor as well. I'm totally baffled as to why this has come up now, given that everything was perfectly content before and I didn't change anything substantial.

Sadly, I don't have a displayport or DVI monitor to check whether linux has a problem detecting those as well. The only workaround people in bug reports seem to have is amdgpu.dc=0 (and fortunately I don't do much graphics-heavy work in linux, so I can just about live with that, irritating though it may be).

Last edited by ConfusedInConsett (2020-05-15 23:26:12)

ConfusedInConsett

Member

Registered: 2020-05-14

Posts: 5

Re: [SOLVED] Screen goes blank during boot

OK, so this is my final word on this matter. The problem was primarily that I am very stupid, perhaps unsurprisingly.

I had managed to loosen the HDMI cable going into the monitor, presumably by kicking it under the desk. Whilst I checked the cables into the back of the computer, I neglected the other end. As a result, Linux wasn't detecting the monitor so didn't output any video. Plugging the monitor back in properly solved the problem and allowed me to remove amdgpu.dc=0.

TL;DR: this entire thread was brought on by an outstanding display (no pun intended) of user incompetence.