Re: [PATCH] Split of raid scan code

[Bean]

On Sat, Aug 16, 2008 at 8:16 PM, Robert Millan <address@hidden> wrote:
> On Sat, Aug 16, 2008 at 05:07:00PM +0800, Bean wrote:
>> Hi,
>>
>> This new patch seperates raid5 and raid6 recover code from raid.c, and
>> place them in module raid5rec.mod and raid6rec.mod. The recover code
>> is only needed when some of the disk are missing or corrupted, which
>> is not common. But raid.c is installed to mbr, so size is important.
>> If there is enough room in mbr for the extra module, they can use
>> --modules option in grub-install to add these modules.
>
> I find this scary in the sense that users need to know about these modules
> to get the benefit of recovery, and even then, they also need to know they
> are affected by this problem when they install GRUB (since otherwise they
> won't be able to bootstrap).
>
> Is it possible to detect whether recover code will be needed when grub-install
> is run, and then either add the extra modules or abort with an error?

Hi,

grub-probe don't use the recover module, so if it have problem at
install time, user would know about it (error message would be
"raid5rec not loaded"). Although, if problem occur afterwards, then
it's unfortunate. It would be possible to detect them and add it to
grub-probe, but the question is, it's not possible to calculate the
size of core.img in grub-probe. if we add it statically, it could
cause grub-install to fail later.

-- 
Bean