From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sun, 10 Mar 2002 08:29:22 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sun, 10 Mar 2002 08:29:13 -0500 Received: from 99dyn73.com21.casema.net ([62.234.30.73]:52137 "EHLO abraracourcix.bitwizard.nl") by vger.kernel.org with ESMTP id ; Sun, 10 Mar 2002 08:29:02 -0500 Message-Id: <200203101328.OAA15987@cave.bitwizard.nl> Subject: RAID superblock.... To: mingo@redhat.com, Linux kernel mailing list , viro@math.psu.edu Date: Sun, 10 Mar 2002 14:28:57 +0100 (MET) From: R.E.Wolff@BitWizard.nl (Rogier Wolff) X-notice1: This Email contains my Email address. This grants you the right X-notice2: to communicate with me using this address, related to the subject X-notice3: in this message. Unsollicitated mass-mailings are explictly X-notice4: forbidden here, and by Dutch law. X-Mailer: ELM [version 2.4ME+ PL60 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi, The MD code I see doing: 488 sb_offset = calc_dev_sboffset(rdev->dev, rdev->mddev, 1); 489 rdev->sb_offset = sb_offset; 490 fsync_dev(dev); 491 set_blocksize (dev, MD_SB_BYTES); 492 bh = bread (dev, sb_offset / MD_SB_BLOCKS, MD_SB_BYTES); where sb_offset is calculated as: 290 if (blk_size[MAJOR(dev)]) 291 size = blk_size[MAJOR(dev)][MINOR(dev)]; Now, for aguments sake, I have a 4k disk. I'd expect the size to be 4 (1k blocks, according to the comment near the definition of blk_size). Thus the "bread" would effectively try to read the block at offset 4k. That would be past the end of my mini-disk, right? I would have expected a "-1" in there somewhere, to get the last block of the dev, and not the block just past the end of the drive. Anyway on the old machine, I still cannot find the raid superblock by hand, but the drives now mount, so the kernel must have been able to locate them somehow...... The machine is still running 2.4.16 + IDE patches for 48 bit addressing. The working machine is an 850MHz PIII w/384Mb RAM, the non-working machine is an AMD 1800+ MP w/1G RAM (with another one of those processors sitting idle close by)... Roger. -- ** R.E.Wolff@BitWizard.nl ** http://www.BitWizard.nl/ ** +31-15-2137555 ** *-- BitWizard writes Linux device drivers for any device you may have! --* * There are old pilots, and there are bold pilots. * There are also old, bald pilots.