From owner-freebsd-current@FreeBSD.ORG Sat Oct 29 22:49:56 2011 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 61B721065679 for ; Sat, 29 Oct 2011 22:49:56 +0000 (UTC) (envelope-from mckusick@mckusick.com) Received: from chez.mckusick.com (chez.mckusick.com [70.36.157.235]) by mx1.freebsd.org (Postfix) with ESMTP id 33E798FC14 for ; Sat, 29 Oct 2011 22:49:56 +0000 (UTC) Received: from chez.mckusick.com (localhost [127.0.0.1]) by chez.mckusick.com (8.14.3/8.14.3) with ESMTP id p9TMYeSU047757; Sat, 29 Oct 2011 15:34:40 -0700 (PDT) (envelope-from mckusick@chez.mckusick.com) Message-Id: <201110292234.p9TMYeSU047757@chez.mckusick.com> To: "deeptech71@gmail.com" In-reply-to: Date: Sat, 29 Oct 2011 15:34:40 -0700 From: Kirk McKusick X-Spam-Status: No, score=0.0 required=5.0 tests=MISSING_MID, UNPARSEABLE_RELAY autolearn=failed version=3.2.5 X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on chez.mckusick.com X-Mailman-Approved-At: Sun, 30 Oct 2011 01:44:33 +0000 Cc: freebsd-current@freebsd.org Subject: Re: panic: ffs_blkfree_cg: freeing free block X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 29 Oct 2011 22:49:56 -0000 > Date: Fri, 28 Oct 2011 11:16:59 +0200 > From: "deeptech71@gmail.com" > To: freebsd-current@freebsd.org > Subject: panic: ffs_blkfree_cg: freeing free block > > A panic occured while I was ``rm -rf''ing a large file&directory tree > (that I just created with untar) on an old drive that I have not used > for a long time. Unfortunately I'm not 100% sure that the filesystem > was clean when I mounted it today. Could that result in such a panic? > > I don't have the intermediate object files for the kernel; now I'm > building the kernel again (from the appropriate, exact sources). That > shouldn't harm debugging, should it? Meanwhile, I'll take any debug > info requests, which I'll attempt to address shortly. This panic happens when the free-block bitmap is corrupted. That can happen due to: 1) An unclean filesystem being mounted (though you should get a warning when you attempt to do this). 2) Bit-rot on the disk that is not checked for before mounting. This is typically only an issue for a disk that has been offline for a long time. 3) Write errors to the disk. There have been no changes to the code that manage the filesystem bitmaps in decades (nearly three decades), so a software cause of this panic is unlikely to have been recently introduced. Hence, I would not spend a lot of time trying to get a backtrace, etc. Kirk McKusick