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Date: Wed, 25 Feb 2009 18:48:39 +0000
From: Jamie Lokier <jamie@shareable.org>
Subject: Re: [Qemu-devel] [6388] Stop VM on ENOSPC error.
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To: qemu-devel@nongnu.org

Anthony Liguori wrote:
> >The idea is that if the guest at least sees the I/O error, then it won't
> >continue writing as if everything were OK. It may not be able to continue
> >normal operation, but it can at least mark the FS read-only and avoid
> >ongoing damage.
> 
> This simply doesn't happen in practice.  The FS needs to write data to 
> the disk in order to remount it read-only.  Once all writes start 
> failing, the errors are cascading.

ext2/3/4 have documented errors=remount-ro / errors=panic mount options.

Don't they work?

(I know that journal integrity is not _exactly_ maintained when write
errors occur at awkward times, as described in my previous mail, but
apart from that don't the above options work?)

-- Jamie