[syslinux] isohybrid: change default offset to 1 to avoid parted troubles

H. Peter Anvin hpa at zytor.com
Tue Dec 8 13:21:50 PST 2009


On 12/08/2009 11:33 AM, Kim Mik wrote:
>> On 12/06/2009 03:37 PM, Sven-Hendrik Haase wrote:
> 
>>> Using the default offset 0, parted will complain about a recursive
>>> partition and will be unable to do any further work on a USB device that
>>> uses an isohybrid image created with offset 0.
>>> Setting offset to 1 will fix this.
>>
>> I will not make this the default.  Rejected.
>>
>>     -hpa
>>
>> -- 
>> H. Peter Anvin, Intel Open Source Technology Center
>> I work for Intel.  I don't speak on their behalf.
> 
> I know it is already rejected, but here is the full explanation by cmdr about the problem:
>   http://gparted-forum.surf4.info/viewtopic.php?id=13581
> 
> Just if anyone is interested in this topic.
> 

The reason I will not make this the default is that it makes it much
harder to use the remaining space on an isohybrid disk for other uses,
since one has to mount the full device to get to the iso9660 filesystem.

Arguably the Right Thing is to add an option to the iso9660 filesystem
driver in the Linux kernel, so that it can handle partition numbers with
an offset.  The only other option is to have to copies of the iso9660
metadata, one for partition use and one for hybrid use, but I would
really rather like to avoid that.

Further complicating it is that there are people who want to be able to
run with a hybrid iso9660 filesystem written to a *partition*, which we
currently do support, but which complicates things further.

	-hpa




More information about the Syslinux mailing list