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=-2.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,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 6800DCA9EB5 for ; Mon, 4 Nov 2019 15:29:28 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 39E472080F for ; Mon, 4 Nov 2019 15:29:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="mZeAxHim" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 39E472080F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=yk6TLtfZUU97QXO7lDjDJeD/bOAEwnf8xXHAPnZhAmc=; b=mZeAxHimlXL0G/ FyDyn2kb2QxwGBjt/DiFV0bejzzs8xP+kNBs6UnohkXChwJ1QkNSeKico4YoBV5cYvFtGymHqHJO2 KwC0JxLozan2s1iYTc86GoDhF1Vm/MX4vALJ0YQvb5bdzxkxj7vi5GX1HUPRtlEIztWtIUsRuj45F Lwm5faae6DCD+R5wd/l0n+dEe3WOlF4Ns90czJ7iDiGIZRyG1rGyUCaemqv5dap5HMtUNA68wrHbb SwxR3/IXNDCtbth9Ce6IfiQM2zSUwRGbwxNFZedR241Fdjfo6ionmrKY/KGp73ky+KAci1xtAENVS yg6IvIl5ABWPqo8VC9vw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iReIH-0002b7-Oy; Mon, 04 Nov 2019 15:29:25 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1iReIE-0002a3-FI for linux-nvme@lists.infradead.org; Mon, 04 Nov 2019 15:29:24 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 396F668BFE; Mon, 4 Nov 2019 16:29:17 +0100 (CET) Date: Mon, 4 Nov 2019 16:29:16 +0100 From: Christoph Hellwig To: Keith Busch Subject: Re: [PATCH] nvme: change nvme_passthru_cmd64's result field. Message-ID: <20191104152916.GB17050@lst.de> References: <20191031050338.12700-1-csm10495@gmail.com> <20191031133921.GA4763@lst.de> <1977598237.90293761.1572878080625.JavaMail.zimbra@kalray.eu> <871357470.90297451.1572879417091.JavaMail.zimbra@kalray.eu> <20191104150151.GA26808@redsun51.ssa.fujisawa.hgst.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20191104150151.GA26808@redsun51.ssa.fujisawa.hgst.com> User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191104_072922_659254_33C51BDE X-CRM114-Status: GOOD ( 16.11 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Sagi Grimberg , Marta Rybczynska , Charles Machalow , linux-kernel , linux-nvme , axboe , Christoph Hellwig Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Tue, Nov 05, 2019 at 12:01:51AM +0900, Keith Busch wrote: > On Mon, Nov 04, 2019 at 03:56:57PM +0100, Marta Rybczynska wrote: > > ----- On 4 Nov, 2019, at 15:51, Charles Machalow csm10495@gmail.com wrote: > > > > > For this one yes, UAPI size changes. Though I believe this IOCTL > > > hasn't been in a released Kernel yet (just RC). Technically it may be > > > changeable as a fix until the next Kernel is released. I do think its > > > a useful enough > > > change to warrant a late fix. > > > > The old one is in UAPI for years. The new one is not yet, right. I'm OK > > to change the new structure. To have compatibility you would have to use > > the new structure (at least its size) in the user space code. This is > > what you'd liek to do? > > Charles is proposing only to modify the recently introduced 64-bit ioctl > struct without touching the existing 32 bit version. He just wanted the > lower 32-bits of the 64-bit result to occupy the same space as the 32-bit > ioctl's result. That space in the 64-bit version is currently occupied > by an implicit struct padding. Except on 32-bit x86, which does not have the padding. Which is why the current layout is so bad, as it breaks 32-it x86 compat. _______________________________________________ Linux-nvme mailing list Linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme