------------------------------ Message: 6 Date: Thu, 29 Jan 2015 01:32:51 +0000 From: Ken Moffat <[email protected]> To: LFS Support List <[email protected]> Subject: Re: [lfs-support] Kernel Config Examined - LFS Still Fails To Boot Message-ID: <20150129013251.GA31396@milliways> Content-Type: text/plain; charset=utf-8
On Wed, Jan 28, 2015 at 07:59:05PM -0500, [email protected] wrote: > After getting the kernel panic on my original development system I thought > perhaps the 10 year old Dell motherboard was just too old to be supported so > I copied the disk and rebuilt the kernel for a 3 year old system using an > Intel P67-based Gigabyte motherboard. Again I used "lspci -K", "lsmod" to > customize the kernel for that system and got the same result, "devtempfs: > error mounting -2" message immediately after "Mounted root (ext4 filesystem) > readonly on 8:3. (link below) > For devtmpfs, you apparently missed [*] Maintain a devtmpfs filesystem to mount at /dev [CONFIG_DEVTMPFS] Possibly, that would be enough to stop init running (no /dev/null, no /dev/zero). I'm not sure that I've ever tried that after we moved to a devtmpfs. Once you have understood why /dev did not get mounted, if you still get a panic from init then you need to run ldd on it to determine what it is linked to (the favourite would be something in /tools, but people occasionally manage to create executables linked to a library which exists on the host but not on the LFS system. > With LFS's grub as a menuentry in Lubuntu's grub.cfg the "MY Dell LFS" entry > does appear in the boot menu and when it's selected it displays stream of > numbers then 4 penguins at the top of the page, then further processing > then.... , "devtempfs: error mounting -2". A stream of numbers ? I would describe it as lines of text scrolling upwards, probably very fast, and perhaps each line starts with a timestamp [ seconds since the kernel booted ]. > > It's worth noting that to copy the newly configured vmlinuz file from my > sda3 (LFS) to sda1's /boot (Lubuntu Host) I mount a FAT USB to LFS and copy > the vmlinuz to the USB, then remove it, mount the USB to the host and copy > the files and ensure the owner/permissions are correct. Yeugh!! You mount lfs from the host to create it, and to fix it. In a term separate from the one where you are fixing LFS, either open a sane interactive root shell (sudo /bin/bash should do that, I guess), or use sudo to copy it. No need for a round-the-houses trip like that. > After a new kernel is built I skip grub-install as the Lubuntu host already > boots. I copy (not move) the vmlinuz.xxxx file to Lubuntu's /boot as > described above and with Lubuntu's grub.cfg edited it appears to be ready to > go, but then not. > Editing grub.cfg sounds good, and since your lfs kernel almost boots, I hope that you are getting there (you appear to have the right disk drivers and the correct main filesystem for this newer machine). ?en -- Nanny Ogg usually went to bed early. After all, she was an old lady. Sometimes she went to bed as early as 6 a.m. ***************** I see now why LFS wouldn't boot and why I had Grub problems. At the end of section 2.4 "Mounting the New Partition" I made a Clonezilla backup of the host's drive which required a reboot. The "mount -v -t ext4 /dev/sda3 $LFS" command never got executed again. And while the LFS variable was always set and chroot properly entered for subsequent steps the mount command directing the build output to sda3 was missing. So it appears LFS got built in the same sda1 partition as the Lubuntu host under /mnt/lfs, and a "df" command while in chroot confirmed the UUID of the Lubuntu partition. In an attempt to move LFS to sda3 I backed-up the lfs tree with the tar command excluding (proc, sys, /dev/pts) and unpacked them in sda3. Then updated-grub. For the first time grub detected a bootable system on sda3 and while I didn't expect LFS to boot with those directories missing it did get much further. The error message read, "mountpoint: /proc: no such file or directory, /procmount: mount point /proc does not exist, mountpoint: /sys: no such file exists. But I expected this. That it continued to detect devices was encouraging. My question is how to best recreate the proc, sys & /dev/pts environment in sda3. They exist in sda1 but to my knowledge neither tar nor rsync will properly copy these directories. Believe repeating LFS steps may accomplish this but after examining the 7.6 docs it isn't clear which ones would do it. Can I recover this way? And if so, what steps need to be redone? Are there other ways to recover? Thanks -- http://lists.linuxfromscratch.org/listinfo/lfs-support FAQ: http://www.linuxfromscratch.org/blfs/faq.html Unsubscribe: See the above information page Do not top post on this list. A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail? http://en.wikipedia.org/wiki/Posting_style
