Re: troubleshooting boot hang

[Chris Murphy]

On Feb 6, 2014, at 8:56 AM, Chris Murphy <address@hidden> wrote:

> 
> GRUB 2.00-25 (Fedora 20) booting a 2011 MacbookPro in EFI mode.
> 
> About 1 in 4 times, I get a boot hang with a particular kernel entry. I 
> choose the entry in grub, press return, the grub menu goes away and is 
> replaced with a black screen with a white _ and that's it. Nothing.
> 
> If I add 'set debug=all' right before the linuxefi line, I get at least 10 
> minutes of text scroll of very verbose information for every boot attempt; 
> even the good kernel entries it's way too verbose and so I give up. What less 
> verbose options are available that will help isolate the problem?
> 
> I just now thought to try 'set debug=all' after the initrdefi line?

So I did that, and this is what I get:

https://dl.dropboxusercontent.com/u/3253801/SSgrubhang.png

I get this with the same kernel, in a VBox VM and on a Mac baremetal. Both EFI 
booting. Both use Btrfs for /boot and rootfs. And both btrfs volumes are 
mounted with LZO compression. But a 3.13.0 kernel consistently boots OK. So 
maybe this is just a bad 3.14 build? It's a Fedora kernel: 
3.14.0-0.rc1.git0.1.fc21.x86_64.


Chris Murphy