Bug#47490: base: mke2fs makes unmountable filesystems; mount doesn't honor -o nocheck
> Jim Dennis <email@example.com> writes:
>> Package: base
>> Version: 19991015
>> Severity: important
>> I was wrong. Earlier I claimed that mount was
>> unable to handle a filesystem with a non-default
>> inode/block ratio ("couldn't mount RDWR"). However,
>> my reasoning was wrong.
>> In actuality the new mke2fs is making filesystems that
>> the latest mount command will not tolerate.
>> I've heard that we need to start using the
>> mount -o nocheck (or check=none) option to mount the
>> newly created filesystems with the "sparse superblock"
>> However, that option is not honored with my copy of
>> mount (2.9x). mke2fs version is 1.15.
>> e2fsprogs version 1.15-3
> The problem goes away with a 2.2.x kernel, which can mount sparse
> superblock ext2 filesystems. Under 2.0.x you can mount the filesystem
> read-only and then remount read-write to trick linux into ignoring the
> feature, but mke2fs should just be fixed not to create sparse
> superblocks under 2.0.x.
> May the Source be with you.
There are several problems and possible solutions.
1st we could backport the sparse superblock support
to the 2.0 (and even the 1.2 and 1.0) kernels.
We could patch mke2fs to check the current kernel version
and default to non-sparse creation when running under
older kernels (with a warning message, perhaps).
We could improve the mount(8) error messages so that it
specified which "optional feature" is involved, and update
the man pages and FAQs so that they have the appropriate
error message(s) listed with recommended fixes and
There is also a workaround involving the use of
tune2fs to force the bits back to the state.
When user space utilities start *requiring* features
of new kernels, we should be more graceful about
the implementation, documentation, errors and warning
Concurrent to my finding this problem on my system
I was reading about it on Tom Oehser's Root/Boot
mailing list. He has a set of preliminary patches
to the 2.0.35 kernel to backport the requisite fs
Jim Dennis firstname.lastname@example.org
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