Re: _primary_constraint(): start_geom is uninitialized if min_geom==0 && cylinder_size < dev->length. Debian bug #602568

[Jim Meyering]

Jean-Christian de Rivaz wrote:
> Jim Meyering a écrit :
>> Jean-Christian de Rivaz wrote:
>> ...
>>> Your patch work fine, thank you for providing it.
>>>
>>> address@hidden:/home/jcdr/parted-git/parted/build-O0# parted/parted
>>> /dev/sdb print
>>> Model: disk2go PURE II (scsi)
>>> Disk /dev/sdb: 5243kB
>>> Sector size (logical/physical): 512B/512B
>>> Partition Table: msdos
>>>
>>> Number  Start  End     Size    Type     File system  Flags
>>>  1      5120B  5243kB  5238kB  primary
>>>
>>> The debug capture in attachment prove that your logic is the right one
>>> for this case.
>>>
>>> Now I just wonder if parted should display FAT16 in the file system
>>> field. Because fdisk do it:
>>>
>>> address@hidden:/home/jcdr/parted-git/parted/build-O0# fdisk -l /dev/sdb
>>>
>>> Disk /dev/sdb: 5 MB, 5242880 bytes
>>> 1 heads, 10 sectors/track, 1024 cylinders
>>> Units = cylinders of 10 * 512 = 5120 bytes
>>> Sector size (logical/physical): 512 bytes / 512 bytes
>>> I/O size (minimum/optimal): 512 bytes / 512 bytes
>>> Disk identifier: 0x00000000
>>>
>>>    Device Boot      Start         End      Blocks   Id  System
>>> /dev/sdb1               2        1024        5115    6  FAT16
>>>
>>> And parted do it for the /dev/sdc (the regular storage device of this
>>> USB key):
>>>
>>> address@hidden:/home/jcdr/parted-git/parted/build-O0# parted/parted
>>> /dev/sdc print
>>> Model: disk2go PURE II (scsi)
>>> Disk /dev/sdc: 2142MB
>>> Sector size (logical/physical): 512B/512B
>>> Partition Table: loop
>>>
>>> Number  Start  End     Size    File system  Flags
>>>  1      0.00B  2142MB  2142MB  fat16
>>
>> Perhaps it should, depending on what it means.
>> Is it reporting just the magic number, or is it reporting
>> the existence of a file system of that type?
>>
>> It seems that 4MiB is the minimum size of a FAT16 file system,
>> and at 2.5MiB, yours is well under the minimum, so with the latter
>> interpretation, parted is correct not to report it as one.
>
> Sorry, I failed to find where this /deb/sdb1 partition is 2.5MiB in
> size. Seem to be 5.1MiB (5238kB, or (1024-2+1)*512*10/2.0**20=4.99MiB
> according to fdisk) to me ( > 4MiB ). This is also confirmed by the
> system while mounting the /deb/sdb1 partition:

Oh.  I looked at sdb1's partition size, rather than the device size.
Thanks for the correction.  In that case, it sounds like a bug.
Can you debug it?

> address@hidden:/home/jcdr/parted-git/parted/build-O0# mount /dev/sdb1 /mnt
> address@hidden:/home/jcdr/parted-git/parted/build-O0# df -h /dev/sdb1
> Filesystem            Size  Used Avail Use% Mounted on
> /dev/sdb1             5.0M     0  5.0M   0% /mnt