Re: [PATCH 4/6] ftrace, x86: make kernel text writable only for conversions

Pavel Machek
2009-02-28T22:17:24Z

On Sat 2009-02-28 23:12:28, Andi Kleen wrote:
> Pavel Machek <pavel@ucw.cz> writes:
>
> [trimmed cc list]
>
> >> If you mean other attributes like large page vs small page: it's normally legal,
> >> with a few exceptions.
> >
> > ...but is it okay on other architectures, like sparc, with funky cache
> > setups?
>
> I don't know for sure (how about you look it up in a sparc manual?), but
> I would assume it's also not safe there. I know it's not allowed in IA64
> at least, with even some stricter rules than on x86.

So using aliases for kernel text rewriting is bad idea because it
would break ia64? That was what the thread was about. (Sorry, no ia64
or sparc manuals nearby).
Pavel
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