Re: Mount on harddisc failed with 1.3.25
Wed, 13 Sep 1995 23:46:49 +0200

: On Wed, 13 Sep 1995 wrote:

: > : After installing the kernel version 1.3.25:
: > : /dev/sda9 not a mount point
: > : With kernel 1.3.18 the mount works perfect!
: >
: > 1. Get a better mount and you'll have better error messages.
: > 2. Recently, the kernel learned how to recognize more partitions.
: > So, if you have a partition that was not recognized before,
: > or just some junk on the disk in a partition table that
: > the kernel did not look at earlier, then all following
: > partitions will have their number increased.
: > Look at the boot messages. Is your old /dev/sda9 now /dev/sda10?

: No. That isn't it, at least on my machine. I have two back to back
: HPFS (OS/2) partitions, hda5 and hda6. Linux recognized these partitions
: without any problem in 1.3.12, but from 1.2.24 on it has only recognized
: the *first* partition, hda5. Wrt hda6, I now get the error quoted above,
: but also a more telling error:

: HPFS: hpfs_superblock_read: not hpfs

The right solution in the case of mafra was that his last logical partition
was not contained in the corresponding extended partition. This is the second
example of the phenomenon that an HPFS partition is followed by a too short
extended partition, followed by that last partition.
I conjecture that your problem is the same.
I conjecture that the OS/2 fdisk is buggy in this sense that the length of
the last extended partition is computed incorrectly.
So, more people will have this problem, and the kernel test for weeding
out garbage partitions is somewhat too strong.
I will submit a patch to genhd.c that on the one hand continues to reject
the garbage partition tables I have seen so far, but on the other hand
accepts the improperly formed tables produced by the OS/2 fdisk.

(If anyone else has problems with a disappeared partition, please
find fdisk-3.02 on sunsite, and mail me the output of "fdisk -l -x -uS"
together with a description of what changed.
Although I am fairly sure that the above analysis is correct, it would
be nice to have more than two examples. It would also be nice to know
whether other fdisks than OS/2's give problems.)

Andries -