From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751862Ab2LWPtJ (ORCPT ); Sun, 23 Dec 2012 10:49:09 -0500 Received: from mx1.redhat.com ([209.132.183.28]:61258 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751154Ab2LWPtG (ORCPT ); Sun, 23 Dec 2012 10:49:06 -0500 Date: Sun, 23 Dec 2012 16:49:10 +0100 From: Oleg Nesterov To: Anton Arapov Cc: Srikar Dronamraju , LKML , Josh Stone , Frank Eigler Subject: Re: [RFC PATCH 5/6] uprobes: add bp_vaddr argument to consumer handler Message-ID: <20121223154910.GA7106@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> <20121222171329.GA20691@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20121222171329.GA20691@redhat.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/22, Oleg Nesterov wrote: > > 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? Wait, probably I was confused by this patch and 4/6... To simplify, lets ignore the normal uprobes. Yes I still think that it would be better to set "regs->ip = orig_return_vaddr" before calling ->handler() and not pass it as an argument. But, probably uprobe_consumer also needs to know bp_vaddr? IOW, the address of the function which we are going to return from? In this case, yes, we also need another argument. And prepare_uretprobe/etc should be changed to record bp_vaddr passed from handle_swbp(). And uretprobe_run_handlers() should pass this bp_vaddr, not orig_return_vaddr. Or I am confused. Anton? Oleg.