Misidentifies ext4 as ext2 and fails to boot

[Tobias Wolf]

Binary package hint: initramfs-tools

Because my laptop has a first-gen SSD, I tried to limit performance degradation over time by creating my root filesystem as ext4 with the option -O ^has_journal.

However the scripts/local script identifies my root fs as ext2, not as ext4. The result is that it fails to mount /root with "invalid args".
The value of $FSTYPE when mount command happens is ext2. When I hardcoded FSTYPE=ext4 in scripts/local it booted normally.

blkid identifies the file system correctly. I suppose the fstype tool from klibc-utils is wrong here.

[Tobias Wolf (towolf)]

$ sudo /usr/lib/klibc/bin/fstype /dev/sda2
FSTYPE=ext2
FSSIZE=8002469888

but

$ sudo blkid -s TYPE -o value /dev/sda2
ext4

[Colin Watson (cjwatson)]

The offending bit of code is:

        /*
         * For now, ext4 requires a journal -- but this may change
         * soon if we get that patch from Google. :-)
         */
        if ((sb->s_feature_compat
             & __cpu_to_le32(EXT3_FEATURE_COMPAT_HAS_JOURNAL)) == 0)
                return 0;

[Colin Watson (cjwatson)]

... and this is also bug 416636.