Re: [PATCH 1/4] x86: entry.S: tidy up several suboptimal insns

Borislav Petkov
2015-02-24T20:35:18Z

On Tue, Feb 24, 2015 at 09:13:03PM +0100, Denys Vlasenko wrote:
> They aren't equal. $1 and $2 in two lowest bits will also
> be interpreted as "userspace" here. "Equal to $3" sends
> a wrong message here to a human reading the code,
> the code doesn't test for CPL=3, it tests for any nonzero CPL.

Doh, of course.

I was going to propose to make it even more explicit:

andb $3, CS(%rsp)...

but that's destructive.

So yours makes it less misleading, actually. To me at least and
obviously.

:-)

--
Regards/Gruss,
Boris.

ECO tip #101: Trim your mails when you reply.
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