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Date: Thu, 20 Mar 2014 16:15:59 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Andy Lutomirski <luto@amacapital.net>
cc: Stefani Seibold <stefani@seibold.net>,
        Greg KH <gregkh@linuxfoundation.org>,
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        Martin Runge <Martin.Runge@rohde-schwarz.com>,
        Andreas Brief <Andreas.Brief@rohde-schwarz.com>
Subject: Re: [PATCH] x86, vdso32: fix out of memory handling setup vDSO
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On Thu, 20 Mar 2014, Andy Lutomirski wrote:
> On Thu, Mar 20, 2014 at 5:30 AM, Thomas Gleixner <tglx@linutronix.de> wrote:
> > On Thu, 20 Mar 2014, Stefani Seibold wrote:
> >> All complains are design decisions not made by me. I will send a patch
> >> for the GFP_ATOMIC thing. For the other one it would be the best to ask
> >> Andy for the reason.
> >
> > I'm not saying it's your fault, but if we rework code, then we really
> > should question such things. What happens if you remove the x32 call
> > and make the x64 subsys thing valid for both cases?
> >
> 
> It's not just that.  The x86_64 and x32 vdso page arrays are *far*
> cleaner than the 32-bit variant.  They manage to do the entire vdso
> setup dance without any allocation at all.  This avoids silly
> questions about error handling and GFP_KERNEL :)
> 
> See vdso/vdso.S for the rather small amount of magic needed.

Is there any reason why we can't use that for x86_32 ?

Thanks,

	tglx