From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AA669CA9EBC for ; Fri, 25 Oct 2019 09:16:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8151921D7B for ; Fri, 25 Oct 2019 09:16:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="qiISsN8D" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2438195AbfJYJQ5 (ORCPT ); Fri, 25 Oct 2019 05:16:57 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:35966 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726409AbfJYJQ5 (ORCPT ); Fri, 25 Oct 2019 05:16:57 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=4HNQYHclJdpz6RgSoEiA+TUKr4RT5EnizppRlQ3bps8=; b=qiISsN8DPpzxJuDWz5BDD7Vsb nyk65gVZOZKlJdImt/zQ93JZf06MrUU84AZ2Rsfj9ptyTwWjr0D3qFev4YZQfFPwJTMmDobsN0BIk BjQ5xOzlgeGTMGH/nj+hTq32C+lTp3YOmIQQjx690HEJY53zroXK96U1kgH2zoh/q6D+yAR7fxkCR NbWzxkhobMh986G8cityFONFpJ+3Kz3hnTzKbLn0NepyOKE4bk0Ic96FQ5eI9MaWJNoVq2rAnv1bg zC0/oopErZGmxqjGq2sEPyLSJLd+UMv9VuOpm84Rd7H5jLuP4VkpiYrpLY9ByFMTMEMhCU+USTsNm TJq8gTq9A==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1iNvi1-00055a-9Y; Fri, 25 Oct 2019 09:16:37 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 3873A3006E3; Fri, 25 Oct 2019 11:15:36 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 07F88201A6624; Fri, 25 Oct 2019 11:16:35 +0200 (CEST) Date: Fri, 25 Oct 2019 11:16:34 +0200 From: Peter Zijlstra To: Petr Mladek Cc: Josh Poimboeuf , x86@kernel.org, linux-kernel@vger.kernel.org, rostedt@goodmis.org, mhiramat@kernel.org, bristot@redhat.com, jbaron@akamai.com, torvalds@linux-foundation.org, tglx@linutronix.de, mingo@kernel.org, namit@vmware.com, hpa@zytor.com, luto@kernel.org, ard.biesheuvel@linaro.org, jeyu@kernel.org, live-patching@vger.kernel.org Subject: Re: [PATCH v4 15/16] module: Move where we mark modules RO,X Message-ID: <20191025091634.GA4114@hirez.programming.kicks-ass.net> References: <20191018073525.768931536@infradead.org> <20191018074634.801435443@infradead.org> <20191021135312.jbbxsuipxldocdjk@treble> <20191021141402.GI1817@hirez.programming.kicks-ass.net> <20191023114835.GT1817@hirez.programming.kicks-ass.net> <20191023170025.f34g3vxaqr4f5gqh@treble> <20191024131634.GC4131@hirez.programming.kicks-ass.net> <20191025064456.6jjrngm4m3mspaxw@pathway.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191025064456.6jjrngm4m3mspaxw@pathway.suse.cz> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 25, 2019 at 08:44:56AM +0200, Petr Mladek wrote: > On Thu 2019-10-24 15:16:34, Peter Zijlstra wrote: > > Right, that really should be able to run early. Esp. after commit > > > > 11e86dc7f274 ("x86/paravirt: Detect over-sized patching bugs in paravirt_patch_call()") > > > > paravirt patching is unconditional. We _never_ run with the indirect > > call except very early boot, but modules should have them patched way > > before their init section runs. > > > > We rely on this for spectre-v2 and friends. > > Livepatching has the same requirement. The module code has to be fully > livepatched before the module gets actually used. Right, and that is just saying that all paravirt RELAs (pv_ops) can basically be deleted from modules. Which avoids the reported problem in yet another way. > It means before mod->init() is called and before the module is moved > into MODULE_STATE_LIVE state. Funny thing, currently ftrace is running code before all that. It runs code before klp_module_coming(), before jump_label patching. My other patch in this thread fixes that.