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From: Philip Seeger <p0h0i0l0i0p@gmail.com>
Subject: Re: Crash during mount -o degraded, kernel BUG at
 fs/btrfs/extent_io.c:2044
To: linux-btrfs@vger.kernel.org
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On 11/01/2015 04:22 AM, Duncan wrote:
> So what btrfs is logging to dmesg on mount here, are the historical error
> counts, in this case expected as they were deliberate during your test,
> nearly 200K of them, not one or more new errors.
>
> To have btrfs report these at the CLI, use btrfs device stats.  To zero

Thanks for clarifying. I forgot to check btrfs dev stats. That explains it.

The 2-drive failure scenario still caused data corruption with 4.3-rc7 
though.


Philip