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Subject: Re: [PATCH] powerpc: Add write barrier before enabling DTL flags
From: Michael Ellerman <michael@ellerman.id.au>
To: Jeremy Kerr <jk@ozlabs.org>
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Date: Wed, 25 Mar 2009 11:44:42 +1100
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On Tue, 2009-03-24 at 16:59 +1100, Jeremy Kerr wrote:
> Michael,
>=20
> > Wouldn't this still be a problem on a UP kernel?
>=20
> I don't believe so - stores should be ordered with respect to the=20
> current CPU, and in the UP case we still get a barrier().

But what if the CPU decides to do the store to the enable_mask before
the stores to the other fields?

cheers

--=20
Michael Ellerman
OzLabs, IBM Australia Development Lab

wwweb: http://michael.ellerman.id.au
phone: +61 2 6212 1183 (tie line 70 21183)

We do not inherit the earth from our ancestors,
we borrow it from our children. - S.M.A.R.T Person

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