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Date: Thu, 29 Jan 2009 02:46:23 -0800
From: Jeremy Fitzhardinge <jeremy@goop.org>
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To: Rusty Russell <rusty@rustcorp.com.au>
CC: Ingo Molnar <mingo@elte.hu>, linux-kernel@vger.kernel.org,
       Xen-devel <xen-devel@lists.xensource.com>,
       the arch/x86 maintainers <x86@kernel.org>,
       Ian Campbell <ian.campbell@citrix.com>,
       Zachary Amsden <zach@vmware.com>,
       Ravikiran Thirumalai <kiran@scalemp.com>
Subject: Re: [PATCH 2 of 7] x86/pvops: add a paravirt_ident functions to allow
 special patching
References: <patchbomb.1233182100@abulafia.goop.org> <79ff4280c71ffeba69d2.1233182102@abulafia.goop.org> <200901291835.49251.rusty@rustcorp.com.au>
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Rusty Russell wrote:
> I think I prefer:
>
> /* make_pte etc and pgd_val etc are identity functions. */
> #define paravirt_native_page_op \
> 	(sizeof(pte_t) == sizeof(u64) ? paravirt_ident_64 : paravirt_ident_32)
>
> Then use that everywhere rather than these defines?
>   

Hm, also I don't think that will work because paravirt_ident_32|64 
return different types.  The compiler might promote paravirt_ident_32 to 
returning a 64-bit number, which would be a bit disastrous. 

    J