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=-5.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 AA43BC63777 for ; Mon, 30 Nov 2020 18:06:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3DCFF2067C for ; Mon, 30 Nov 2020 18:06:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="JsQVEEQ7" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387946AbgK3SGL (ORCPT ); Mon, 30 Nov 2020 13:06:11 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53268 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387868AbgK3SGK (ORCPT ); Mon, 30 Nov 2020 13:06:10 -0500 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [IPv6:2001:4d48:ad52:32c8:5054:ff:fe00:142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7069AC0613CF for ; Mon, 30 Nov 2020 10:05:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender: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-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=U/dq4XBKLjIj8o+Y1ijdonAPuVA02wsCQ9Xrid3YVv8=; b=JsQVEEQ7J0mZEkLPjCIxwK5WW wc9G9f4ifbWp8TKDAgLPZOOe3Fb2OsOhiyfEYgZ7fO1TnaSagY37SkpCMGxKDyrLHjIkPHHn3SG6s 0teQKL/DneiDNSVZZaWQ1o2hWrJ17+u1s1DDaP/OTOg0ud8a1NZaqy7i6al7ORzC3YikovIimbbyg D6tRbmWabLpSKuPC89FzKRThltwZm69SGfjXmuwZRwI8N3vfypSjcMCTI/qVlSpf5uOqCDs92oqzW 0UWuvjUF4fGBKiUuXC0BsEFdHj7/GnIEURUWr9dQnDCYPkaWC+s+KQIIrGUnWavbNQeAiFGQJBLHB 7k8mkew0Q==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:38084) by pandora.armlinux.org.uk with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1kjnYD-0007Lg-SN; Mon, 30 Nov 2020 18:05:25 +0000 Received: from linux by shell.armlinux.org.uk with local (Exim 4.92) (envelope-from ) id 1kjnYC-0005Cs-RS; Mon, 30 Nov 2020 18:05:25 +0000 Date: Mon, 30 Nov 2020 18:05:24 +0000 From: Russell King - ARM Linux admin To: Linus Torvalds List-Id: Cc: Doug Anderson , Arnd Bergmann , SoC Team , Linux ARM , Linux Kernel Mailing List , Ulf Hansson Subject: Re: [GIT PULL] ARM: SoC fixes for v5.10, part 3 Message-ID: <20201130180523.GZ1551@shell.armlinux.org.uk> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: Russell King - ARM Linux admin Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 30, 2020 at 09:44:03AM -0800, Linus Torvalds wrote: > On Mon, Nov 30, 2020 at 9:04 AM Doug Anderson wrote: > > > > Without static assignment, maybe we could do numbering of MMC devices > > in some type of a pre-probe routine? Is that what you're suggesting? > > Yes. > > So basically, the way the async probing works for say SCSI is that we > have multiple "layers of asynchroniety". We have the usual "init calls > done asynchronously", but then within the init calls themselves you > can start sub-scans asynchronously. > > In order to get reliable ordering between multiple controllers, the > PCI bus is probed in order in pci_init() (or whatever), so each SCSI > controller gets called in a fixed order. > > That then gets to scsi_scan_host() does that async_schedule() thing to > actually scan the SCSI buses on that host. I'm afraid that you don't get stable device numbering on x86. You get something that _looks_ like stable device numbering, but it really isn't. If you think that /dev/sda for example is always the machine's internal HDD, that is wrong. I have a HP Pavilion laptop with its internal HDD with a Windows installation. Because I didn't want to destroy that in any way, I bought an external USB3 SATA enclosure and SSD, and installed Debian Stable on there. When I installed Debian stable, the HDD was /dev/sda and the SSD was /dev/sdb. When I boot Debian, the SSD is /dev/sda and the internal HDD is /dev/sdb. Maybe /dev/sda through /dev/sdd should be reserved for internal motherboard drives? -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!