From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752630Ab2JFHRn (ORCPT ); Sat, 6 Oct 2012 03:17:43 -0400 Received: from e31.co.us.ibm.com ([32.97.110.149]:46537 "EHLO e31.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750981Ab2JFHRk (ORCPT ); Sat, 6 Oct 2012 03:17:40 -0400 Date: Sat, 6 Oct 2012 12:48:08 +0530 From: Srikar Dronamraju To: Oleg Nesterov Cc: Ingo Molnar , Peter Zijlstra , Ananth N Mavinakayanahalli , Anton Arapov , Sebastian Andrzej Siewior , linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/4] uprobes: Kill set_orig_insn()->is_swbp_at_addr() Message-ID: <20121006071808.GF27781@linux.vnet.ibm.com> Reply-To: Srikar Dronamraju References: <20120923201921.GA27424@redhat.com> <20120923201950.GA27456@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <20120923201950.GA27456@redhat.com> User-Agent: Mutt/1.5.20 (2009-06-14) X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12100607-7282-0000-0000-00000DA8E750 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Oleg Nesterov [2012-09-23 22:19:50]: > Unlike set_swbp(), set_orig_insn()->is_swbp_at_addr() makes sense, > although it can't prevent all confusions. > > But the usage of is_swbp_at_addr() is equally confusing, and it adds > the extra get_user_pages() we can avoid. > > This patch removes set_orig_insn()->is_swbp_at_addr() but changes > write_opcode() to do the necessary checks before replace_page(). > > Perhaps it also makes sense to ensure PAGE_MAPPING_ANON in unregister > case. > > find_active_uprobe() becomes the only user of is_swbp_at_addr(), > we can change its semantics. > > Signed-off-by: Oleg Nesterov > --- Acked-by: Srikar Dronamraju