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=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED autolearn=unavailable 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 7A7D5C4360F for ; Thu, 4 Apr 2019 20:11:36 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B361120651 for ; Thu, 4 Apr 2019 20:11:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=raptorengineering.com header.i=@raptorengineering.com header.b="K2TjjzNm" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B361120651 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=raptorengineering.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 44ZvGs4HpNzDqRK for ; Fri, 5 Apr 2019 07:11:33 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=raptorengineering.com (client-ip=23.155.224.45; helo=mail.rptsys.com; envelope-from=tpearson@raptorengineering.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=raptorengineering.com Authentication-Results: lists.ozlabs.org; dkim=pass (1024-bit key; secure) header.d=raptorengineering.com header.i=@raptorengineering.com header.b="K2TjjzNm"; dkim-atps=neutral X-Greylist: delayed 520 seconds by postgrey-1.36 at bilbo; Fri, 05 Apr 2019 07:09:52 AEDT Received: from mail.rptsys.com (mail.rptsys.com [23.155.224.45]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 44ZvDw0RHCzDqQG for ; Fri, 5 Apr 2019 07:09:51 +1100 (AEDT) Received: from localhost (localhost [127.0.0.1]) by mail.rptsys.com (Postfix) with ESMTP id BC34FE64BF8; Thu, 4 Apr 2019 15:01:06 -0500 (CDT) Received: from mail.rptsys.com ([127.0.0.1]) by localhost (vali.starlink.edu [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id aZDxJ46WG23u; Thu, 4 Apr 2019 15:01:05 -0500 (CDT) Received: from localhost (localhost [127.0.0.1]) by mail.rptsys.com (Postfix) with ESMTP id 28A2DE634F7; Thu, 4 Apr 2019 15:01:05 -0500 (CDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.rptsys.com 28A2DE634F7 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=raptorengineering.com; s=B8E824E6-0BE2-11E6-931D-288C65937AAD; t=1554408065; bh=UOXZistDtfIVLs1k2qCBucJryKN2lZmP/gp8TjK5bx0=; h=Date:From:To:Message-ID:MIME-Version; b=K2TjjzNm46u1tmFyW8wBZvXL/9qrV060qp0bmdAUszA/AfzFhFHMozT/+CQLJ6tEX ub93M5n+xF5CvGrHtMQMHqbWWHxUnisL589Y8qRBBKqV76ZmcQYXzPqWciCP/Bi1pe qPtvm5GnL3UD24XrVS6pKAWky+XoQ8sXaxTusuu0= X-Virus-Scanned: amavisd-new at rptsys.com Received: from mail.rptsys.com ([127.0.0.1]) by localhost (vali.starlink.edu [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id 96swXYcdsRvL; Thu, 4 Apr 2019 15:01:04 -0500 (CDT) Received: from vali.starlink.edu (unknown [192.168.3.2]) by mail.rptsys.com (Postfix) with ESMTP id B798DE6505A; Thu, 4 Apr 2019 15:01:04 -0500 (CDT) Date: Thu, 4 Apr 2019 15:01:04 -0500 (CDT) From: Timothy Pearson To: Jiri Kosina Message-ID: <401506569.4710878.1554408064001.JavaMail.zimbra@raptorengineeringinc.com> In-Reply-To: References: <91b92d8182d2f114d92c95689fcd4bb1a8dda1b0.1554396090.git.jpoimboe@redhat.com> Subject: Re: [PATCH RFC 3/5] powerpc/speculation: Add support for 'cpu_spec_mitigations=' cmdline options MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Mailer: Zimbra 8.5.0_GA_3042 (ZimbraWebClient - GC73 (Linux)/8.5.0_GA_3042) Thread-Topic: powerpc/speculation: Add support for 'cpu_spec_mitigations=' cmdline options Thread-Index: dinaMtutIL4nwvFGZxvsYJw0doq+RA== X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Peter Zijlstra , Catalin Marinas , Will Deacon , Paul Mackerras , "H . Peter Anvin" , Ingo Molnar , Andrea Arcangeli , linux-s390@vger.kernel.org, x86@kernel.org, Jon Masters , Waiman Long , linux-arch@vger.kernel.org, Heiko Carstens , linuxppc-dev@lists.ozlabs.org, Borislav Petkov , Andy Lutomirski , Josh Poimboeuf , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, Greg Kroah-Hartman , linux-kernel@vger.kernel.org, Tyler Hicks , Martin Schwidefsky , Linus Torvalds Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Will be joining in ~ 5 mins. Getting Chromium set up here. ----- Original Message ----- > From: "Jiri Kosina" > To: "Josh Poimboeuf" > Cc: "Peter Zijlstra" , "Heiko Carstens" , "Paul Mackerras" > , "H . Peter Anvin" , "Ingo Molnar" , "Andrea Arcangeli" > , linux-s390@vger.kernel.org, x86@kernel.org, "Will Deacon" , "Linus > Torvalds" , "Catalin Marinas" , "Waiman Long" > , linux-arch@vger.kernel.org, "Jon Masters" , "Borislav Petkov" , > "Andy Lutomirski" , "Thomas Gleixner" , linux-arm-kernel@lists.infradead.org, > "Greg Kroah-Hartman" , linux-kernel@vger.kernel.org, "Tyler Hicks" , > "Martin Schwidefsky" , linuxppc-dev@lists.ozlabs.org > Sent: Thursday, April 4, 2019 2:49:05 PM > Subject: Re: [PATCH RFC 3/5] powerpc/speculation: Add support for 'cpu_spec_mitigations=' cmdline options > On Thu, 4 Apr 2019, Josh Poimboeuf wrote: > >> Configure powerpc CPU runtime speculation bug mitigations in accordance >> with the 'cpu_spec_mitigations=' cmdline options. This affects >> Meltdown, Spectre v1, Spectre v2, and Speculative Store Bypass. > [ ... snip ... ] >> - if (!no_nospec) >> + if (!no_nospec && cpu_spec_mitigations != CPU_SPEC_MITIGATIONS_OFF) > > '!no_nospec' is something that I am sure will come back to hunt me in my > bad dreams. > > But that's been there already, and fixing it is out of scope of this > patch. Other than that, as discussed previously -- I really like this new > global option. Feel free to add > > Reviewed-by: Jiri Kosina > > for the whole set. > > Thanks, > > -- > Jiri Kosina > SUSE Labs