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Date: Fri, 22 Mar 2013 10:07:26 +0530
From: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
To: Oleg Nesterov <oleg@redhat.com>
Subject: Re: [PATCH] powerpc/uprobes: teach uprobes to ignore gdb breakpoints
Message-ID: <20130322043726.GA26183@in.ibm.com>
References: <20130320104033.GA19844@in.ibm.com>
 <20130320122639.GA29541@redhat.com> <20130320124301.GA30887@redhat.com>
 <20130320154245.GB8246@in.ibm.com> <20130320160728.GB20352@redhat.com>
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On Thu, Mar 21, 2013 at 05:00:02PM +0100, Oleg Nesterov wrote:
> On 03/21, Ananth N Mavinakayanahalli wrote:
> ?
> > On Wed, Mar 20, 2013 at 05:07:28PM +0100, Oleg Nesterov wrote:
> > > On 03/20, Ananth N Mavinakayanahalli wrote:
> > > >
> > > > On Wed, Mar 20, 2013 at 01:43:01PM +0100, Oleg Nesterov wrote:
> > > > > On 03/20, Oleg Nesterov wrote:
> > > > > >
> > > > > IOW, if I wasn't clear... Lets forget about gdb/etc for the moment.
> > > > > Suppose we apply the patch below. Will uprobes on powerpc work?
> > > > >
> > > > > If yes, then your patch should be fine. If not, we probably need more
> > > > > changes.
> > > >
> > > > Yes, it will work fine.
> > >
> > > Even if this new insn is conditional?
> >
> > Yes.
> 
> But this can't be true. If it is conditional, it won't always generate a
> trap, this means uprobe won't actually work.

I meant to say, uprobes if we use a conditional trap instruction as long
as the condition is met.

Ananth