Re: [PATCH] 32-bit UID support for 2.3.30pre6 (important update)

Manfred Spraul (manfreds@colorfullife.com)
Mon, 06 Dec 1999 19:29:58 +0100

Chris Wing wrote:
> > The knowledge about the legacy support should be completely hidden
> > within copy_xxx_to_user().
>
> This was the way I wrote it originally :)
>
> The only problem with this code is that it increases the stack usage (due
> to the fact that both a msqid_ds and msqid64_ds have to be allocated at
> the same time).

Stack usage it not critical (the conversion functions could eat 800
bytes without any problems) _except_ in semctl_main() and sys_semop().

sys_semop():
uses "struct sembuf", you didn't change that structure, no conversion
needed.

semctl_main():
only GETALL and SETALL need lots of stack space, and only IPC_STAT needs
a conversion function.

I think you can safely ignore the stack problem:
even _if_ semctl_main() needs to much stack space [I doubt that], it
would be easy to
* decrease SEMMSL_FAST
* or split semctl_main().

--
	Manfred




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