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 Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 351CEC19F2A for ; Thu, 11 Aug 2022 15:50:45 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4M3WVX2tnCz3c4w for ; Fri, 12 Aug 2022 01:50:44 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.crashing.org (client-ip=63.228.1.57; helo=gate.crashing.org; envelope-from=segher@kernel.crashing.org; receiver=) Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) by lists.ozlabs.org (Postfix) with ESMTP id 4M3WTf66tdz3bbl for ; Fri, 12 Aug 2022 01:49:58 +1000 (AEST) Received: from gate.crashing.org (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.14.1) with ESMTP id 27BFlqBW006139; Thu, 11 Aug 2022 10:47:52 -0500 Received: (from segher@localhost) by gate.crashing.org (8.14.1/8.14.1/Submit) id 27BFlpgk006136; Thu, 11 Aug 2022 10:47:51 -0500 X-Authentication-Warning: gate.crashing.org: segher set sender to segher@kernel.crashing.org using -f Date: Thu, 11 Aug 2022 10:47:51 -0500 From: Segher Boessenkool To: Christophe Leroy Subject: Re: [PATCH v2 11/14] powerpc/64s: Clear/restore caller gprs in syscall interrupt/return Message-ID: <20220811154751.GG25951@gate.crashing.org> References: <20220725063111.120926-1-rmclure@linux.ibm.com> <20220811151302.GF25951@gate.crashing.org> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.4.2.3i 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: Rohan McLure , "linuxppc-dev@lists.ozlabs.org" , "npiggin@gmail.com" Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Thu, Aug 11, 2022 at 03:39:58PM +0000, Christophe Leroy wrote: > > > Le 11/08/2022 à 17:13, Segher Boessenkool a écrit : > > Hi! > > > > On Mon, Jul 25, 2022 at 04:31:11PM +1000, Rohan McLure wrote: > >> + /* > >> + * Zero user registers to prevent influencing speculative execution > >> + * state of kernel code. > >> + */ > >> + NULLIFY_GPRS(5, 12) > >> + NULLIFY_NVGPRS() > > > > "Nullify" means "invalidate", which is not what this does or is for :-( > > Would "Zeroise" be more appropriate ? That is probably a good compromise, yes. It obviously is a verb, its meaning is clear and unamiguous, and there is precedent for it even :-) Thanks, Segher