From: Chris Murphy <lists@colorremedies.com>
To: Btrfs BTRFS <linux-btrfs@vger.kernel.org>
Subject: confusing behavior when supers mismatch
Date: Sun, 10 Mar 2019 17:09:01 -0600 [thread overview]
Message-ID: <CAJCQCtQ9nduarOggGv98Oxo6SE9QBKhm7oxYXFE9UsMbVTnwow@mail.gmail.com> (raw)
In the case where superblock 0 at 65536 is valid but stale (older than
the others):
1. btrfs check doesn't complain, the stale super is used for the check
2. when mounting, super 0 is used, no complaints at mount time, fairly
quickly the newer supers are overwritten
Is this expected? In particular, in lieu of `btrfs rescue super`
behavior which considers super 0 a bad super, and offers to fix it
from the newer ones, and when I answer y, it replaces super 0 with
newer information from the other supers.
I think the `btrfs rescue` behavior is correct. I would expect that
all the supers are read at mount time, and if there's discrepancy that
either there's code to suspiciously sanity check the latest roots in
the newest super, or it flat out fails to mount. Mounting based on
stale super data seems risky doesn't it?
--
Chris Murphy
next reply other threads:[~2019-03-10 23:09 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-10 23:09 Chris Murphy [this message]
2019-03-10 23:18 ` confusing behavior when supers mismatch Chris Murphy
2019-03-11 1:17 ` Qu Wenruo
2019-03-11 3:20 ` Chris Murphy
2019-03-11 4:58 ` Qu Wenruo
2019-03-11 5:19 ` Chris Murphy
2019-03-11 12:26 ` Nikolay Borisov
2019-03-11 12:35 ` Qu Wenruo
2019-03-11 12:37 ` Nikolay Borisov
2019-03-11 13:27 ` Qu Wenruo
2019-03-11 14:38 ` Anand Jain
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