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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 713BED68B38 for ; Thu, 14 Nov 2024 16:44:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Q+VAMTocin9VVuS4dIQtEJ7svLpRdLRVIZb2WTHyhR0=; b=Qv4cGJPWKchbNtDlIg/3u9HCWn QuHAXaEDz4+djDUmmrfTcq70jDRfM3/CZaPTUeTh2LAtdaaCvKn6gNNOlnZiHLq+2x2Buc0xtzga7 sva9OsyBcpDmjJr5HTYmOx+Afjzzpsgyolye6ZiqfDhxKO0nlqlDCxbze1R5eZktV/fdF9Da8ZGWO bStrD+SLUyZueIWFIIvxZUP+BpTkrczcCx04YgVQmM3Rm3mKGvHR5+ZDPi4GWs1gFDCUhN5WOjM9p bcCKpmif8PoaPMu4Epf23y0bFoWjub63LUS3BR2VlLBHDTrHR9q7HsH7xaW2ZteNQGiZqypmdYbPh uu2PYuJw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tBcxk-00000000BZB-2dj3; Thu, 14 Nov 2024 16:44:56 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tBcvk-00000000Az3-1xUp for linux-nvme@lists.infradead.org; Thu, 14 Nov 2024 16:42:53 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id A7BD468C7B; Thu, 14 Nov 2024 17:42:45 +0100 (CET) Date: Thu, 14 Nov 2024 17:42:45 +0100 From: Christoph Hellwig To: Keith Busch Cc: Christoph Hellwig , Keith Busch , linux-nvme@lists.infradead.org Subject: Re: [PATCHv2 2/2] nvme-pci: use sgls for all user requests if possible Message-ID: <20241114164245.GA4132@lst.de> References: <20241112210620.2650523-1-kbusch@meta.com> <20241112210620.2650523-3-kbusch@meta.com> <20241113045859.GC20379@lst.de> <20241114055642.GB10948@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii 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-20241114_084252_649542_48E59B1C X-CRM114-Status: GOOD ( 16.57 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Thu, Nov 14, 2024 at 08:53:49AM -0700, Keith Busch wrote: > Only admin users can access this path by default. You have to opt-in for > it, so it's not exploitable unless you ask for it. We do allow non-privileged users to send I/O commands and a small whitelist of admin commands by default, limited by the CSE effects. > I can't see disabling > the interface entirely. In a previous version of this patch, I had the > kernel tainted if you tried to do passthrough without SGL support. Would > that be a fair compromise if I reintroduce that behavior? Taint might be a bit too strong, but a one-time message in the log might be useful.