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=-5.8 required=3.0 tests=BAYES_00,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 6586CC433DB for ; Thu, 11 Feb 2021 07:08:00 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 C8F2264E6F for ; Thu, 11 Feb 2021 07:07:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C8F2264E6F 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=merlin.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=UPuuIlZyD3KNQNzSskZwv8EDCtZbc8oZEil55uXehEE=; b=LrSKoURllMR5Ftl98aTD3MhsO WVBEQL/XewcOzuLUA7uN5/e1JX9om8dcEZZiBMymg2+Mb+zKvxo8zmS8dyqZakNBjkyGm1I7ny+ze O7kkaxI9nf/lJwqOyInu5Q6DZm2K0zduzC+pg7x4xntdBSYPF/53eoHSpCBw2aDmiwLOnExx3+GUI DL2L6bJEBTUzfbivdnbwqxZ3DC9C9swfFbwfGmzgan9kT7enOC1gFN0691lAJRtynbc3eTgM9PykX bjVaXLlQ3ur9/BsGfz1+qY4dA82EY6dfJjQSTm8LmiYNhLoXnK0VwmJ6f3MnpZiY1fXutY6/Uhpp+ IinRkPaew==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1lA64x-0002v5-AK; Thu, 11 Feb 2021 07:07:55 +0000 Received: from verein.lst.de ([213.95.11.211]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1lA64t-0002uB-PX for linux-nvme@lists.infradead.org; Thu, 11 Feb 2021 07:07:52 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 770A06736F; Thu, 11 Feb 2021 08:07:48 +0100 (CET) Date: Thu, 11 Feb 2021 08:07:48 +0100 From: Christoph Hellwig To: Chaitanya Kulkarni Subject: Re: [PATCH] nvme-pci: prevent SK Hynix PE8000 from using Write Zeroes command Message-ID: <20210211070748.GA13852@lst.de> References: <20210209045902.72345-1-gtiwari@redhat.com> <211078952.30654328.1612955843198.JavaMail.zimbra@redhat.com> <20210210131557.GB29904@lst.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: 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-20210211_020752_010325_FE3647EE X-CRM114-Status: GOOD ( 15.34 ) 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: "hch@infradead.org" , "kbusch@kernel.org" , Gopal Tiwari , Christoph Hellwig , "linux-nvme@lists.infradead.org" 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 Wed, Feb 10, 2021 at 10:11:15PM +0000, Chaitanya Kulkarni wrote: > On 2/10/21 5:20 AM, Christoph Hellwig wrote: > > MDTS vs Write Zeroes is a common misconception. We had that discussion > > in the NVMe working group, and while the text should pretty clear that > > MDTS only applies to data transfers many implementators did not understand > > that, which is why we added the clarification you quoted. > > > > Also the next NVMe spec will allow devices to advertise an explicit > > Write Zeroes limit, take a look at TP4040 from the "NVM Express 1.4 Ratified > > TPs" at https://nvmexpress.org/developers/nvme-specification/. > > > > So I think limiting to MDTS unless the new WZSL is set might be a fail > > safe option, even if it is more pessimistic than what the spec says. > > > > I'd also love to retest most Write Zeroes quirks with that in place. > > Do you prefer some variant of the following patch (totally untested)? OR > something else ? Somwhat. As said I suspect defaulting to MDTS with a big fat comment might make most sense unless the new WZSL is set. _______________________________________________ Linux-nvme mailing list Linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme