Subject: Further union_fs panics
To: None <current-users@NetBSD.ORG>
From: Julian Bean <>
List: current-users
Date: 04/03/1996 01:17:05
I am seeing more and more now.  This one occurs whenever I try to patch
files which are in the underneath filesystem (expecting the patched ones to
appear in the top layer)...

Hunk #1 succeeded at 23.
panic: ufs_direnter2: compact2
Stopped at _Debugger+0x6
db> trace
_Debugger(1b760,7cff3,8b1c5c,18,8b1d08)+ 6
_panic(7cff3,0,1,0,1f) + 34
_ufs_direnter2(703cc80,8b1d2c,7069b80,703bc00,7028000) + 7a
_union_link(8b1ee0) + 17e
_sys_link(703bc00,8b1f88,8b1f80) + 168
_sycall(9) + 13a
_trap0() + e

Something is badly wrong here.  I don't really see how this can be to do
with my custom kernel, although it is annoying that it has started just
now.  I am going to remove the top layer and reconstruct it...

OK, I've done that for the directory it broke in above, and it fixed it,
only to break in another.  I will rebuild all dodgy directories and that
will hopefully crack it.. which it has..

There appears to be some kind of file system corruption here that fsck
doesn't deal with which screws up union mounts.  My intuition is that its
something to do with white-outs...


P.S. Incidentally, it doesn't ever manage to sync the disks.

|  Jelibean aka  |           |  6 Evelyn Road      |
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