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=-5.3 required=3.0 tests=BAYES_00, 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 ED0B6C433E6 for ; Wed, 3 Feb 2021 09:52:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A08BF64E93 for ; Wed, 3 Feb 2021 09:52:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233661AbhBCJwk (ORCPT ); Wed, 3 Feb 2021 04:52:40 -0500 Received: from verein.lst.de ([213.95.11.211]:50338 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233644AbhBCJwb (ORCPT ); Wed, 3 Feb 2021 04:52:31 -0500 Received: by verein.lst.de (Postfix, from userid 2407) id 671BF6736F; Wed, 3 Feb 2021 10:51:48 +0100 (CET) Date: Wed, 3 Feb 2021 10:51:48 +0100 From: Christoph Hellwig To: Filippo Sironi Cc: serebrin@amazon.com, dwmw@amazon.co.uk, kbusch@kernel.org, axboe@fb.com, hch@lst.de, sagi@grimberg.me, linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] nvme: Add 48-bit DMA address quirk Message-ID: <20210203095148.GA8897@lst.de> References: <20210203094338.19473-1-sironi@amazon.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210203094338.19473-1-sironi@amazon.de> User-Agent: Mutt/1.5.17 (2007-11-01) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Feb 03, 2021 at 10:43:38AM +0100, Filippo Sironi wrote: > Certain NVMe controllers don't support 64-bit DMA addresses. Instead, > they are limited to 48-bit DMA addresses. Let's add a quirk to use them > properly. WTF? This is such a grave NVMe spec compiance bug that I do not think we should support this buggy mess in Linux.