Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965426Ab2B2Rlk (ORCPT ); Wed, 29 Feb 2012 12:41:40 -0500 Received: from mail-gy0-f174.google.com ([209.85.160.174]:45476 "EHLO mail-gy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756452Ab2B2Rlh (ORCPT ); Wed, 29 Feb 2012 12:41:37 -0500 Authentication-Results: mr.google.com; spf=pass (google.com: domain of mcgrathr@google.com designates 10.50.168.99 as permitted sender) smtp.mail=mcgrathr@google.com; dkim=pass header.i=mcgrathr@google.com MIME-Version: 1.0 In-Reply-To: <20120229170933.GA6149@redhat.com> References: <1330140111-17201-1-git-send-email-wad@chromium.org> <1330140111-17201-10-git-send-email-wad@chromium.org> <20120227175407.GD10608@redhat.com> <20120228164335.GC3664@redhat.com> <20120229161437.GA3078@redhat.com> <20120229170933.GA6149@redhat.com> From: Roland McGrath Date: Wed, 29 Feb 2012 09:41:13 -0800 Message-ID: Subject: Re: [PATCH v11 10/12] ptrace,seccomp: Add PTRACE_SECCOMP support To: Oleg Nesterov Cc: Will Drewry , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-doc@vger.kernel.org, kernel-hardening@lists.openwall.com, netdev@vger.kernel.org, x86@kernel.org, arnd@arndb.de, davem@davemloft.net, hpa@zytor.com, mingo@redhat.com, peterz@infradead.org, rdunlap@xenotime.net, tglx@linutronix.de, luto@mit.edu, eparis@redhat.com, serge.hallyn@canonical.com, djm@mindrot.org, scarybeasts@gmail.com, indan@nul.nu, pmoore@redhat.com, akpm@linux-foundation.org, corbet@lwn.net, eric.dumazet@gmail.com, markus@chromium.org, coreyb@linux.vnet.ibm.com, keescook@chromium.org, Denys Vlasenko Content-Type: text/plain; charset=ISO-8859-1 X-System-Of-Record: true Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 831 Lines: 19 I don't think TIF_NOTIFY_RESUME is apropos here. That only triggers on returning to user mode, i.e. after syscall exit. But regardless of the exact implementation details, I don't think it will be prohibitive to add some means by which the fast-path can back off before actual syscall entry and go to the slow path for ptrace reporting. Since there is no strong reason to think it can't be reorganized that way later, I don't see any good rationale for constraining the seccomp-filter feature definition based on a plan to optimize the implementation in the future. Thanks, Roland -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/