From patchwork Fri Sep 18 01:56:39 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Randy Dunlap X-Patchwork-Id: 11783829 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 79A5E92C for ; Fri, 18 Sep 2020 01:56:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3CE2D20838 for ; Fri, 18 Sep 2020 01:56:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="lSvsaled" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726109AbgIRB4v (ORCPT ); Thu, 17 Sep 2020 21:56:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52394 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726101AbgIRB4v (ORCPT ); Thu, 17 Sep 2020 21:56:51 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 11A1CC061756; Thu, 17 Sep 2020 18:56:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=DzqRDNd51AABXfHvOGClQ6GjXbZcogsHuLBhYu1WzRk=; b=lSvsaledKpcxMeyBZOttoe+mHR wrJNYGfwWLdsfUAWG8SWRljXsdUTfBsaWL3QxiGB2bVVvx5/bH8NfPbckU2hv1ViLPDNW7HOsNlYM OvBKGjZlvo1+4N+ON4QKwPw9OA0EhumdjbwXq6Nwfvy87PtHDuswdV8usfpPea/NAn+/U8JnF85fm W6lh1oecPRvGQmhh3UvrC+U/HfzoqNLrvTIS+FpwTaYjP/+i5cdrkJwyW8OFJZ73mRjKIr0tHeI9X joJZ+AQHJLLc2brs22awxiNLZahBPmBCFSfPK8rliauq1Om9AYh9hvQrhAImrEwJ6qW+2lCQ/gLEU y+UGFJaw==; Received: from [2601:1c0:6280:3f0::19c2] (helo=smtpauth.infradead.org) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kJ5do-0007g2-3I; Fri, 18 Sep 2020 01:56:48 +0000 From: Randy Dunlap To: linux-kernel@vger.kernel.org Cc: Randy Dunlap , Karel Zak , Paul Gortmaker , Jens Axboe , linux-block@vger.kernel.org, Alexander Viro , Martin Mares , linux-video@atrey.karlin.mff.cuni.cz, "H. Peter Anvin" , Jonathan Corbet , linux-doc@vger.kernel.org Subject: [RFC PATCH v2 1/2] Documentation/admin-guide: README & svga: remove use of "rdev" Date: Thu, 17 Sep 2020 18:56:39 -0700 Message-Id: <20200918015640.8439-2-rdunlap@infradead.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200918015640.8439-1-rdunlap@infradead.org> References: <20200918015640.8439-1-rdunlap@infradead.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org "rdev" is considered antiquated, ancient, archaic, obsolete, deprecated {choose any or all}. Remove use of "rdev" and "vidmode" (a symlink to rdev) in admin-guide/README.rst and admin-guide/svga.rst. "rdev" was removed from util-linux in 2010: https://git.kernel.org/pub/scm/utils/util-linux/util-linux.git/commit/?id=a3e40c14651fccf18e7954f081e601389baefe3f Signed-off-by: Randy Dunlap Cc: Karel Zak Cc: Paul Gortmaker Cc: Jens Axboe Cc: linux-block@vger.kernel.org Cc: Alexander Viro Cc: Martin Mares Cc: linux-video@atrey.karlin.mff.cuni.cz Cc: "H. Peter Anvin" Cc: Jonathan Corbet Cc: linux-doc@vger.kernel.org Acked-by: Martin Mares --- v2: Modify when the Video Mode Selection feature is available (thanks, Peter). No email address for these: nCc: Werner Almesberger nCc: Stephen Tweedie nCc: Peter MacDonald Documentation/admin-guide/README.rst | 6 +++--- Documentation/admin-guide/svga.rst | 7 ++++--- 2 files changed, 7 insertions(+), 6 deletions(-) --- lnx-59-rc5.orig/Documentation/admin-guide/README.rst +++ lnx-59-rc5/Documentation/admin-guide/README.rst @@ -322,9 +322,9 @@ Compiling the kernel reboot, and enjoy! If you ever need to change the default root device, video mode, - ramdisk size, etc. in the kernel image, use the ``rdev`` program (or - alternatively the LILO boot options when appropriate). No need to - recompile the kernel to change these parameters. + etc. in the kernel image, use your bootloader's boot options + where appropriate. No need to recompile the kernel to change + these parameters. - Reboot with the new kernel and enjoy. --- lnx-59-rc5.orig/Documentation/admin-guide/svga.rst +++ lnx-59-rc5/Documentation/admin-guide/svga.rst @@ -12,7 +12,8 @@ Intro This small document describes the "Video Mode Selection" feature which allows the use of various special video modes supported by the video BIOS. Due to usage of the BIOS, the selection is limited to boot time (before the -kernel decompression starts) and works only on 80X86 machines. +kernel decompression starts) and works only on 80X86 machines that are +booted through BIOS firmware (as opposed to through UEFI, kexec, etc.). .. note:: @@ -23,7 +24,7 @@ kernel decompression starts) and works o The video mode to be used is selected by a kernel parameter which can be specified in the kernel Makefile (the SVGA_MODE=... line) or by the "vga=..." -option of LILO (or some other boot loader you use) or by the "vidmode" utility +option of LILO (or some other boot loader you use) or by the "xrandr" utility (present in standard Linux utility packages). You can use the following values of this parameter:: @@ -41,7 +42,7 @@ of this parameter:: better to use absolute mode numbers instead. 0x.... - Hexadecimal video mode ID (also displayed on the menu, see below - for exact meaning of the ID). Warning: rdev and LILO don't support + for exact meaning of the ID). Warning: LILO doesn't support hexadecimal numbers -- you have to convert it to decimal manually. Menu From patchwork Fri Sep 18 01:56:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Randy Dunlap X-Patchwork-Id: 11783831 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 6A67892C for ; Fri, 18 Sep 2020 01:56:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4A1B720838 for ; Fri, 18 Sep 2020 01:56:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="mpZsUV3i" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726267AbgIRB4x (ORCPT ); Thu, 17 Sep 2020 21:56:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52400 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726009AbgIRB4x (ORCPT ); Thu, 17 Sep 2020 21:56:53 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D95ECC06174A; Thu, 17 Sep 2020 18:56:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=2vCDwiPR2yaZdRJxWxgBGGfBruV3oiY2jDxmJ1dPfyo=; b=mpZsUV3iI6ME1iCtPwx9U99TlA 0ZfoagZAb4dVB+cyPmH41GaHhHtB+BlVvd6r36kL2xoOqwzkl8JAmZAHbF/cNqnO39UKHenqfth1T 1kwEpObXDx6XJPYQEKERAKHcvMks33r7A83lLSJrz3PZQSJbDUR4Yf4wKem+U8N0dr37MvGZGU7y0 bi1u883t8b9N03102tksoVnbhyyy7cxHTJeZmiesqs6nPT6R5jpTdZdHo45mY07Uo/V6DTQAP4uOr vuliLZd+CNneK5dprmMajckBnuiUUKz7nPWjrZr7J921cUxukwKrAo3J48YefZ2a93iUkWQZxDxf9 vzmZzIWQ==; Received: from [2601:1c0:6280:3f0::19c2] (helo=smtpauth.infradead.org) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kJ5dr-0007g2-5n; Fri, 18 Sep 2020 01:56:51 +0000 From: Randy Dunlap To: linux-kernel@vger.kernel.org Cc: Randy Dunlap , Karel Zak , Paul Gortmaker , Jens Axboe , linux-block@vger.kernel.org, Alexander Viro , Martin Mares , linux-video@atrey.karlin.mff.cuni.cz, "H. Peter Anvin" , Jonathan Corbet , linux-doc@vger.kernel.org Subject: [RFC PATCH v2 2/2] Documentation/admin-guide: blockdev/ramdisk: remove use of "rdev" Date: Thu, 17 Sep 2020 18:56:40 -0700 Message-Id: <20200918015640.8439-3-rdunlap@infradead.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200918015640.8439-1-rdunlap@infradead.org> References: <20200918015640.8439-1-rdunlap@infradead.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Remove use of "rdev" from blockdev/ramdisk.rst and update admin-guide/kernel-parameters.txt. "rdev" is considered antiquated, ancient, archaic, obsolete, deprecated {choose any or all}. "rdev" was removed from util-linux in 2010: https://git.kernel.org/pub/scm/utils/util-linux/util-linux.git/commit/?id=a3e40c14651fccf18e7954f081e601389baefe3f Signed-off-by: Randy Dunlap Cc: Karel Zak Cc: Paul Gortmaker Cc: Jens Axboe Cc: linux-block@vger.kernel.org Cc: Alexander Viro Cc: Martin Mares Cc: linux-video@atrey.karlin.mff.cuni.cz Cc: "H. Peter Anvin" Cc: Jonathan Corbet Cc: linux-doc@vger.kernel.org --- v2: modify Changelog date format. No email address for these: nCc: Werner Almesberger nCc: Stephen Tweedie nCc: Peter MacDonald Documentation/admin-guide/blockdev/ramdisk.rst | 70 ++++---------- Documentation/admin-guide/kernel-parameters.txt | 9 - 2 files changed, 27 insertions(+), 52 deletions(-) --- lnx-59-rc5.orig/Documentation/admin-guide/blockdev/ramdisk.rst +++ lnx-59-rc5/Documentation/admin-guide/blockdev/ramdisk.rst @@ -6,7 +6,7 @@ Using the RAM disk block device with Lin 1) Overview 2) Kernel Command Line Parameters - 3) Using "rdev -r" + 3) Using "rdev" 4) An Example of Creating a Compressed RAM Disk @@ -59,51 +59,27 @@ default is 4096 (4 MB). rd_size See ramdisk_size. -3) Using "rdev -r" ------------------- +3) Using "rdev" +--------------- -The usage of the word (two bytes) that "rdev -r" sets in the kernel image is -as follows. The low 11 bits (0 -> 10) specify an offset (in 1 k blocks) of up -to 2 MB (2^11) of where to find the RAM disk (this used to be the size). Bit -14 indicates that a RAM disk is to be loaded, and bit 15 indicates whether a -prompt/wait sequence is to be given before trying to read the RAM disk. Since -the RAM disk dynamically grows as data is being written into it, a size field -is not required. Bits 11 to 13 are not currently used and may as well be zero. -These numbers are no magical secrets, as seen below:: - - ./arch/x86/kernel/setup.c:#define RAMDISK_IMAGE_START_MASK 0x07FF - ./arch/x86/kernel/setup.c:#define RAMDISK_PROMPT_FLAG 0x8000 - ./arch/x86/kernel/setup.c:#define RAMDISK_LOAD_FLAG 0x4000 - -Consider a typical two floppy disk setup, where you will have the -kernel on disk one, and have already put a RAM disk image onto disk #2. - -Hence you want to set bits 0 to 13 as 0, meaning that your RAM disk -starts at an offset of 0 kB from the beginning of the floppy. -The command line equivalent is: "ramdisk_start=0" - -You want bit 14 as one, indicating that a RAM disk is to be loaded. -The command line equivalent is: "load_ramdisk=1" - -You want bit 15 as one, indicating that you want a prompt/keypress -sequence so that you have a chance to switch floppy disks. -The command line equivalent is: "prompt_ramdisk=1" - -Putting that together gives 2^15 + 2^14 + 0 = 49152 for an rdev word. -So to create disk one of the set, you would do:: - - /usr/src/linux# cat arch/x86/boot/zImage > /dev/fd0 - /usr/src/linux# rdev /dev/fd0 /dev/fd0 - /usr/src/linux# rdev -r /dev/fd0 49152 +"rdev" is an obsolete, deprecated, antiquated utility that could be used +to set the boot device in a Linux kernel image. -If you make a boot disk that has LILO, then for the above, you would use:: +Instead of using rdev, just place the boot device information on the +kernel command line and pass it to the kernel from the bootloader. + +You can also pass arguments to the kernel by setting FDARGS in +arch/x86/boot/Makefile and specify in initrd image by setting FDINITRD in +arch/x86/boot/Makefile. - append = "ramdisk_start=0 load_ramdisk=1 prompt_ramdisk=1" +Some of the kernel command line boot options that may apply here are:: -Since the default start = 0 and the default prompt = 1, you could use:: + ramdisk_start=N + ramdisk_size=M - append = "load_ramdisk=1" +If you make a boot disk that has LILO, then for the above, you would use:: + append = "ramdisk_start=N ramdisk_size=M" 4) An Example of Creating a Compressed RAM Disk ----------------------------------------------- @@ -151,12 +127,9 @@ f) Put the RAM disk image onto the flopp dd if=/tmp/ram_image.gz of=/dev/fd0 bs=1k seek=400 -g) Use "rdev" to set the boot device, RAM disk offset, prompt flag, etc. - For prompt_ramdisk=1, load_ramdisk=1, ramdisk_start=400, one would - have 2^15 + 2^14 + 400 = 49552:: - - rdev /dev/fd0 /dev/fd0 - rdev -r /dev/fd0 49552 +g) Make sure that you have already specified the boot information in + FDARGS and FDINITRD or that you use a bootloader to pass kernel + command line boot options to the kernel. That is it. You now have your boot/root compressed RAM disk floppy. Some users may wish to combine steps (d) and (f) by using a pipe. @@ -167,11 +140,14 @@ users may wish to combine steps (d) and Changelog: ---------- +SEPT-2020 : + + Removed usage of "rdev" + 10-22-04 : Updated to reflect changes in command line options, remove obsolete references, general cleanup. James Nelson (james4765@gmail.com) - 12-95 : Original Document --- lnx-59-rc5.orig/Documentation/admin-guide/kernel-parameters.txt +++ lnx-59-rc5/Documentation/admin-guide/kernel-parameters.txt @@ -2441,8 +2441,7 @@ memblock=debug [KNL] Enable memblock debug messages. - load_ramdisk= [RAM] List of ramdisks to load from floppy - See Documentation/admin-guide/blockdev/ramdisk.rst. + load_ramdisk= [RAM] [Deprecated] lockd.nlm_grace_period=P [NFS] Assign grace period. Format: @@ -3921,9 +3920,7 @@ Param: - step/bucket size as a power of 2 for statistical time based profiling. - prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk - before loading. - See Documentation/admin-guide/blockdev/ramdisk.rst. + prompt_ramdisk= [RAM] [Deprecated] prot_virt= [S390] enable hosting protected virtual machines isolated from the hypervisor (if hardware supports @@ -3981,6 +3978,8 @@ ramdisk_size= [RAM] Sizes of RAM disks in kilobytes See Documentation/admin-guide/blockdev/ramdisk.rst. + ramdisk_start= [RAM] RAM disk image start address + random.trust_cpu={on,off} [KNL] Enable or disable trusting the use of the CPU's random number generator (if available) to