Message-ID: <4B0BAC76.3080202@redhat.com>
Date: Tue, 24 Nov 2009 11:50:46 +0200
From: Avi Kivity <avi@redhat.com>
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To: Johannes Berg <johannes@sipsolutions.net>
CC: kvm <kvm@vger.kernel.org>, linux-kernel <linux-kernel@vger.kernel.org>,
       Steven Rostedt <srostedt@redhat.com>
Subject: Re: kvmmmu tracing
References: <1258974375.7094.158.camel@johannes.local>
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On 11/23/2009 01:06 PM, Johannes Berg wrote:
> Commit f691fe1da7e2715137d21ae5a80bec64db4625db is really broken wrt.
> the userspace interface for tracing because of the weird
> KVM_MMU_PAGE_PRINTK macro.
>
>    

Can you explain what is wrong with it?

> Maybe we should have a "unsafe for export" flag for events, if they do
> strange things like that?
>
> As it stands, I can't use trace-cmd on an x86 machine that has kvm
> enabled because it will try to read all the kvm stuff. Arguably, it
> should only try to parse it when it needs it (i.e. not for me) but still
> it's very inconvenient to export something to userspace that it cannot
> possibly understand.
>    

Is userspace reading mmutrace.h?  When the structure attributes can be 
exported via /sys/kernel/debug/tracing?


-- 
error compiling committee.c: too many arguments to function

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