DN2820FYKH (BIOS version:0028)
The kernel stalls at "Loading, please wait" or sometimes at the the next line where udevd is launched.
I did a bisect which identified the commit 21855ff5bcbdd075e1c99772827a84912ab083dd "intel_pstate: Set turbo VID for BayTrail" as the cause.
I also confirmed it by reverting the commit on v3.15 which fixed the stall.
What distribution are you using?
Does the boot continue or is it hung there forever?
Can you attach the contents of /proc/cpuinfo and the output of dmidecode.
I will start tracking down a system like yours to reproduce the failure.
forever is such a long time - a few times I have had it stalled for 10-15 min. before I forced a reboot.
Created attachment 139981 [details]
dmidecode ouput for DN2820FYKH
Created attachment 139991 [details]
/proc/cpuinfo for DN2820FYKH
Is it possible to try the latest BIOS? The BIOS affects the way P state requests are handled. The requirement to set the turbo VID popped up in a recent update to the BIOS writers guide section on selecting P states.
I have hardware on the way in any case.
updated the BIOS to 0034, the only change is that now the stall happens a little later.
it happens after:
"sd 0:0:0:0: [sda] Attached SCSI device"
or the next line:
"tsc: Refined TSC clocksource...."
I suspect it is more or less coincidental where the stall happen.
Created attachment 140341 [details]
Panic Transcription during boot
Transcription of image of panic during boot. If you would like the picture this was transcribed from, please let me know.
Created attachment 140351 [details]
/proc/cpuinfo for Erich Eickmeyer
Created attachment 140361 [details]
git bisect log for Erich Eickmeyer
Reference the attachments I just created. Stable kernels 3.14.6 and above fail to boot on my hardware.
Just tested Kernel 3.16.0-rc1, same result.
Same here with 0034 DN2820FYKH bios. Reverting above change solves the problem.
Created attachment 140421 [details]
Patch to fix regression on N2820
Revert the bitmask changes that were part of the BIOS writers guide update
That fixed for me, thank you Dirk.
Fixed for me as well on N3520 system. Thank you, Dirk.
Dirk, you will push the patch to upstream, right?
(In reply to Zhang Rui from comment #16)
> Dirk, you will push the patch to upstream, right?
Yes but it was 7 minutes after Rafael's vacation mail got to me ;-(
Author: Dirk Brandewie <firstname.lastname@example.org>
Date: Fri Jun 20 07:27:58 2014 -0700
intel_pstate: Fix setting VID