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Date: Sat, 22 Dec 2012 18:13:29 +0100
From: Oleg Nesterov <oleg@redhat.com>
To: Anton Arapov <anton@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>,
        LKML <linux-kernel@vger.kernel.org>, Josh Stone <jistone@redhat.com>,
        Frank Eigler <fche@redhat.com>
Subject: Re: [RFC PATCH 5/6] uprobes: add bp_vaddr argument to consumer
	handler
Message-ID: <20121222171329.GA20691@redhat.com>
References: <1356088596-17858-1-git-send-email-anton@redhat.com> <1356088596-17858-6-git-send-email-anton@redhat.com> <20121222163545.GE18082@redhat.com>
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Forgot to ask...

On 12/22, Oleg Nesterov wrote:
>
> On 12/21, Anton Arapov wrote:
> >
> >  struct uprobe_consumer {
> > -	int (*handler)(struct uprobe_consumer *self, struct pt_regs *regs);
> > +	int (*handler)(struct uprobe_consumer *self, unsigned long bp_vaddr, struct pt_regs *regs);
>
> It seems that we can do better...
>
> Just change regs->ip before calling ->handler().

Josh, Frank, will it work for you?

I assume that stap never needs the "real" ->ip after bp, it only needs
to know which bp the task hits. And once again, in any case ->ip will
be changed after ->handler() is called.

Oleg.