From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 8 Nov 2000 17:31:13 +0100 From: Andrea Arcangeli Subject: [linux-lvm] Re: LVM 2.2 snapshot bug Message-ID: <20001108173113.B3650@inspiron.suse.de> References: <20001107174504.A5834@inspiron.suse.de> Mime-Version: 1.0 Content-Disposition: inline In-Reply-To: ; from riel@conectiva.com.br on Wed, Nov 08, 2000 at 12:04:50AM +0100 Sender: owner-linux-lvm Errors-To: owner-linux-lvm List-Id: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Rik van Riel Cc: linux-lvm@msede.com, marcelo@conectiva.com.br, "Stephen C. Tweedie" , Chris Mason On Wed, Nov 08, 2000 at 12:04:50AM +0100, Rik van Riel wrote: > I haven't checked yet if LVM actually returns an error > to ext3 or if it just silently (well, except for the After ll_rw_block(WRITE) returns the buffer will be clean and _not_ uptodate. That's the only way a blockdevice reports I/O errors to highlevel layers. > Exposing a read-only device as read-write to the users > will cause a bit of confusion, yes :) I agree. > Though I guess Stephen's decision to do log replay on > read-only mounted filesystems on read-write block > devices is certainly a defendable decision. Btw, don't Yes, I'm not complaining that decsion. What I am saying is that the major bug here is that ext3 Oopses the kernel when it gets I/O errors because of faulty harddisk during recovery, not that LVM forgot to set the ro_bits just like the floppy disk when it's read only and the floppy disk case is likely to be unfixable infact. I can't see any bug in LVM that could explain an Oops. >the reiserfs people do the same? About reiserfs I don't know what it does but I guess it does the same. Chris, could you try to mount reiserfs in readonly mode on a snapshot blockdevice and see what happens? Andrea