Re: [gentoo-user] boots, but not on first try

[Fernando Rodriguez]

On Thursday, August 06, 2015 11:34:56 PM Felix Miata wrote:
> If I followed the kernel instructions page correctly, its E8400 Core2Duo
> wasn't in need of an initrd, and so did not get one. Main deviation from
> suggestions/defaults was enabling HPFS filesystems. Result was 6001056 byte
> 4.0.5. openSUSE Tumbleweed 4.0.5 kernel is virtually identical at 6004656,
> but there is also its 8712096 initrd.
>
> I reached the bottom of
> https://wiki.gentoo.org/wiki/Handbook:X86/Installation/Bootloader and
> restarted host before clicking on link to next step. Before emerging
> recommendations in the Tools instructions page I took a timeout to emerge
mc.
> The process involved 22 packages, more than I had any idea mc depended on,
> but I guess that's at least partly because the installation to that point
was
> so very skeletal.
>
> I got ahead of things I suppose on the bootloader instructions, which
include
> no example for Grub 0.97. I did emerge -s grub to identify the package name,
> then did 'emerge --ask sys-boot/grub-static' without first looking for any
> instructions, after which I somehow found https://wiki.gentoo.org/wiki/GRUB
> and its instruction saying 'sys-boot/grub:0'. Having already emerged
> sys-boot/grub-static without the :0 appendage, I punted instead of looking
up
> meaning of :0, running 'emerge --ask sys-boot/grub-static:0'. That produced
4
> beeps prior to emerge exit, which the previous emerge did not do. Next I set
> Grub up according to its man page: grub> find /boot/grub/stage1; grub> root
> (hd0,21); grub> setup (hd0,21), then adjusted grub.conf.
>
> First boot try I used Gentoo's Grub 0.97 (grub.conf) chainloaded from
> openSUSE's Grub 0.97-194 (menu.lst). Kernel quickly panic'd. I recognized
> nothing on the screen to indicate why, though I had seen such things before,
> among them, not syncing: VFS: Unable to mount root fs on unknown block(0,0).
> / filesystem is mkfs.ext4 created while running openSUSE kernel 3.12.44.
>
> Second try I used menu.lst. Fastest boot I've ever experienced!
>
> I then tweaked on grub.conf, but #3 try using it also panic'd (~@1.37), also
> producing no help I recognized.
>
> So now after some experimenting with cmdline arguments I'm on ~#10, headed
> into https://wiki.gentoo.org/wiki/Handbook:X86/Installation/Finalizing ,
> wondering why a Gentoo sample/prototype-based Grub stanza produces panic.
>
> Panicing grub.conf cmdline arguments:
> root=/dev/ram0 real_root=/dev/sda22 ipv6.disable=1 net.ifnames=0 splash=0
> video=1024x768@60 3
>
> Working grub.conf cmdline arguments:
> root=/dev/sda22 ipv6.disable=1 net.ifnames=0 splash=0 video=1024x768@60 3
>
> Why is root=/dev/ram0 real_root= in the sample/prototype?

That looks like the command line for the initrd. change it to root=/dev/sda22, 
if you have all the right modules for your HD built-in compiled it should 
boot. If you still get that panic boot from a live cd and configure the kernel 
with:

make localmodconfig

then: 
make menuconfig
and check that the block device modules are built-in.

finally,

make
make modules_install
make install

and reboot.

> 4.0.5's /boot/config* FWIW:
> http://fm.no-ip.com/Tmp/Linux/G/config-4.0.5-gentoo-gx780.txt
>

-- 
Fernando Rodriguez