Re: [PATCH 1/12] i386: Distinguish absolute symbols

Gerd Hoffmann
2006-10-09T07:35:54Z

>> looks odd. What's the point in putting a gap before __smp_alt_end? Moving
>> __smp_alt_end to before the ALIGN doesn't prevent the warning.
>>

> Please find attached a patch for the same. I am also copying Gerd Hoffmann,
> who introduced this ALIGN. Gerd, can you please confirm that above ALIGN()
> is not required and the patch attached should be fine.

The data between __smp_alt_start and __smp_alt_end will be released at
boot time in some cases (UP machine, kernel without CPU_HOTPLUG, ...).

Releasing memory works at page granularity only, thats why I added the
alignment. I think you can't simply drop it.

> o There seems to be one extra ALIGN(4096) before symbol __smp_alt_end. The
> only usage of __smp_alt_end is to mark the end of smp alternative
> sections so that this memory can be freed. As a physical page is freed
> one has to just make sure that there is no other data on the same page
> where __smp_alt_end is pointing. There is already a ALIGN(4096) after
> this section which should take care of the above issue. Hence it looks
> like the ALIGN(4096) before __smp_alt_end is redundant and not required.

Hmm, ok, it should work then. How about adding a comment to make sure
the align after __smp_alt_end doesn't get dropped by accident?

cheers,

Gerd

--
Gerd Hoffmann <kraxel@suse.de>