ch. 8.3: Segmentation fault after make mrproper

lfs_novice · 04-05-2016, 12:22 PM

starting in chapter 8.3 with "make mrproper" I get the message

Quote:

Segmentation fault (core dumped)

Ok I was trying to use linux 4.5 instead of 4.4.2

Quote:

root:/sources# ls linux*
linux-4.5.tar.xz
root:/sources# cd linux-4.5
root:/sources/linux-4.5# make mrproper
Segmentation fault (core dumped)
root:/sources/linux-4.5#

What can I do now?

Many Thanks in advanced

hazel · 04-05-2016, 02:40 PM

The segmentation error comes from make. It happened to me too! The cause is not having your device directory set up properly, which is an easy mistake to make in chroot. Go back to the section on setting up the chroot environment in Chapter 6. Check each of the mounts/bindings specified and compare with the actual ones as output by mount. One of them will be missing. Add it in and try again.

lfs_novice · 04-06-2016, 12:59 AM

That's what I used as described in ch. 6.72

Quote:

chroot "$LFS" /usr/bin/env -i \
HOME=/root TERM="$TERM" PS1='\u:\w\$ ' \
PATH=/bin:/usr/bin:/sbin:/usr/sbin \
/bin/bash --login

and my fstab looks like this (I'm using separate partitions for each dirctory as mentioned in 2.2.1.3. Convenience Partitions):

Quote:

# Begin /etc/fstab

# file system mount-point type options dump fsck
# order

/dev/sda3 / ext4 defaults 1 1
/dev/sda5 swap swap pri=1 0 0
/dev/sda7 /boot ext4 defaults 1 1
/dev/sda8 /usr/src ext4 defaults 1 1
/dev/sda9 /tmp ext4 defaults 1 1
/dev/sda10 /home ext4 defaults 1 1
/dev/sda11 /usr ext4 defaults 1 1
/dev/sda12 /opt ext4 defaults 1 1
/dev/sda6 /mnt/daten vfat noauto,user,quiet,showexec,iocharset=ISO-8859-15,codepage=850
1 1

# End /etc/fstab

Is there anything wrong?

hazel · 04-06-2016, 01:27 AM

The fstab doesn't matter. What matters is the current state of what is mounted, as shown by the mount command. And I seem not to have make myself quite clear; it isn't the chroot command itself that has gone wrong but the mounting and binding of the various host dynamic filesystems just before you chroot. Something was missed out. It's easy to do; the eye slides over one line and there you are!

Open a terminal in the host and run mount from there. Check that everything that should be mounted on $LFS is there: proc, sys, dev, dev/pts.

lfs_novice · 04-06-2016, 12:37 PM

I don't know if there is anything missing...
Thats what I get back running the mount command in the host system

Quote:

user@Lifebook:/etc$ mount
/dev/sda3 on / type ext4 (rw,errors=remount-ro)
proc on /proc type proc (rw,noexec,nosuid,nodev)
sysfs on /sys type sysfs (rw,noexec,nosuid,nodev)
none on /sys/fs/cgroup type tmpfs (rw)
none on /sys/fs/fuse/connections type fusectl (rw)
none on /sys/kernel/debug type debugfs (rw)
none on /sys/kernel/security type securityfs (rw)
udev on /dev type devtmpfs (rw,mode=0755)
devpts on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=0620)
tmpfs on /run type tmpfs (rw,noexec,nosuid,size=10%,mode=0755)
none on /run/lock type tmpfs (rw,noexec,nosuid,nodev,size=5242880)
none on /run/shm type tmpfs (rw,nosuid,nodev)
none on /run/user type tmpfs (rw,noexec,nosuid,nodev,size=104857600,mode=0755)
none on /sys/fs/pstore type pstore (rw)
/dev/sda6 on /media/Daten type vfat (rw,uid=1000,umask=0022)
binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,noexec,nosuid,nodev)
systemd on /sys/fs/cgroup/systemd type cgroup (rw,noexec,nosuid,nodev,none,name=systemd)
gvfsd-fuse on /run/user/1000/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,user=user)
/dev/sda4 on /mnt/lfs type ext4 (rw)
/dev/sda7 on /mnt/lfs/boot type ext4 (rw)
/dev/sda10 on /mnt/lfs/home type ext4 (rw)
/dev/sda11 on /mnt/lfs/usr type ext4 (rw)
/dev/sda12 on /mnt/lfs/opt type ext4 (rw)
/dev/sda9 on /mnt/lfs/tmp type ext4 (rw)
/dev/sda8 on /mnt/lfs/usr/src type ext4 (rw)
gvfsd-fuse on /home/user/.gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev)

if I run mount in chroot I get this:

Quote:

root:/sources/linux-4.5# mount
mount: failed to read mtab: No such file or directory

How should it look like regarding proc, sys, dev, dev/pts? I don't see a /dev/pts directory in chroot environment:

Quote:

root:/proc# ls --> empty
root:/proc# cd /sys
root:/sys# ls --> empty
root:/sys# cd /dev
root:/dev# ls --> only two files, no /dev/pts
console null
root:/dev#

Keith Hedger · 04-06-2016, 05:14 PM

You need to mountncertain hostbsystem directorys on $LFS BEFORE chrooting ie:

Code:

mount -v --bind /dev $LFS/dev
mount -vt devpts devpts $LFS/dev/pts -o gid=5,mode=620
mount -vt proc proc $LFS/proc
mount -vt sysfs sysfs $LFS/sys
mount -vt tmpfs tmpfs $LFS/run

Where LFS= your lfs system.
These commands need to be run as root, after exiting the chroot don't forget to unmount them.

lfs_novice · 04-08-2016, 09:53 AM

Thank you very much for your help! It took me three or four attempts (i couldn't chroot anymore) but now it is working.