From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeremy Fitzhardinge <jeremy@goop.org>
Subject: Re: Why disable vdso by default with CONFIG_PARAVIRT?
Date: Mon, 11 Dec 2006 17:44:28 -0800
Message-ID: <457E097C.5030208@goop.org>
References: <457E0460.4030107@goop.org> <457E08FE.6050600@vmware.com>
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Sender: linux-kernel-owner@vger.kernel.org
To: Zachary Amsden <zach@vmware.com>
Cc: Andi Kleen <ak@suse.de>, Virtualization Mailing List <virtualization@lists.osdl.org>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
List-Id: virtualization@lists.linuxfoundation.org

Zachary Amsden wrote:
> Jeremy Fitzhardinge wrote:
>> Hi Andi,
>>
>> What problem do they cause together?  There's certainly no problem with
>> Xen+vdso (in fact, its actually very useful so that it picks up the
>> right libc with Xen-friendly TLS).
>>   
>
> Methinks the compat VDSO support got broken in the config?  Paravirt +
> COMPAT_VDSO are incompatible. 

Yes, that's true, but I'm looking at arch/i386/kernel/sysenter.c:

#ifdef CONFIG_PARAVIRT
unsigned int __read_mostly vdso_enabled = 0;
#else
unsigned int __read_mostly vdso_enabled = 1;
#endif

I can't think of any reason why that should be necessary.

    J