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Date: Fri, 26 Jul 2013 19:50:00 -0000
From: Eric Wong <normalperson@yhbt.net>
To: "Frank Ch. Eigler" <fche@redhat.com>
Cc: Systemtap List <systemtap@sourceware.org>
Subject: Re: copy faults from user_string* functions
Message-ID: <20130726195020.GA7739@dcvr.yhbt.net>
References: <20130726063634.GA32443@dcvr.yhbt.net> <y0miozxmeqe.fsf@fche.csb> <20130726175602.GA5773@dcvr.yhbt.net> <20130726194220.GA7389@dcvr.yhbt.net>
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Eric Wong <normalperson@yhbt.net> wrote:
> Eric Wong <normalperson@yhbt.net> wrote:
> > Is there any optional way to get stap to trigger page faults to get
> > that data?
> 
> I could restructure my code to pass integers instead of strings as
> a workaround, but I'm trying my best to be lazy :>

Actually, simply reordering my code to access the string (via mempcpy)
before the trace point seems to work around the issue.  I'll keep the
try{}catch{} just in case, though.