From owner-freebsd-fs Mon Mar 4 16:41:50 2002 Delivered-To: freebsd-fs@freebsd.org Received: from salmon.maths.tcd.ie (salmon.maths.tcd.ie [134.226.81.11]) by hub.freebsd.org (Postfix) with SMTP id CD7A737B405; Mon, 4 Mar 2002 16:41:45 -0800 (PST) Received: from walton.maths.tcd.ie by salmon.maths.tcd.ie with SMTP id ; 5 Mar 2002 00:41:44 +0000 (GMT) To: Kris Kennaway Cc: Alfred Perlstein , Kirk McKusick , Matthew Dillon , Finch , fs@FreeBSD.ORG, fanf@chiark.greenend.org.uk, peter@FreeBSD.ORG Subject: [Probably Solved] Re: UFS panic on -stable In-Reply-To: Your message of "Sun, 03 Mar 2002 14:35:11 PST." <20020303143511.A46076@xor.obsecurity.org> Date: Tue, 05 Mar 2002 00:41:43 +0000 From: Ian Dowse Message-ID: <200203050041.aa89711@salmon.maths.tcd.ie> Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org In message <20020303143511.A46076@xor.obsecurity.org>, Kris Kennaway writes: >> > Okay, bad news..gohan10 just panicked with the 'ufs_dirbad: bad dir' >> Hrm, have we had anyone check the machine's fans and reset the cabling? >At this point I think I'm just going to give up and go back to a >known-good (hoped-good :) snapshot so I can try and get this damn Kris will probably have further details, but it looks as if most of these panics were caused by a swap configuration error. Normally swapon(2) will return EBUSY if the specified device is already configured for swapping, but it seems to be unable to detect this situation if the original swapon() was performed using a device node on a different filesystem. On the package-building cluster the configuration has a MFS /dev and then another /dev (maybe within a chroot) on a FFS filesystem. It appears that something was doing `swapon /dev/ad0b' in both, and both were succeeding. So anything that got swapped out (including the pages making up the MFS filesystems) would most likely get overwritten before being swapped back in later. That certainly explains all the MFS corruption, ufs_dirbad, dup alloc, freeing free inode, and maybe the double faults. I'm not sure if it could have caused the other panics. Ian To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message