FreeBSD 10 panic with "ffs_valloc: dup alloc"

[Kirk McKusick]

> Date: Mon, 24 Nov 2014 00:11:40 +0300
> From: Lev Serebryakov <lev at freebsd.org>
> To: freebsd-fs at freebsd.org
> Subject: Re: FreeBSD 10 panic with "ffs_valloc: dup alloc"
> 
> On 23.11.2014 22:59, Lev Serebryakov wrote:
> 
>> Filesystem in question is clean after panic reboot (!) SU and
>> "native" journal are used. Memory check is Ok. System is amd64,
>> r269936. What could I add to this information to help track & fix
>> this bug?
>  Ok, I could reproduce it. It is triggered by "svnsync" of FreeBSD
> "base" repository. 3 times in a row.
> 
> -- 
> // Lev Serebryakov AKA Black Lion

I don't know what you mean by "native" journal. Is this SUJ or is
it the journal GEOM layer?

In either case, you should take the system down to single user.
Run fsck over the filesystem in question. It will most likely
find something wrong and fix it. After that the problem will be
gone. The problem with any type of journalling is that if a
filesystem error creeps in either because of a write error or
a lying disk (e.g., it says that it did the write, but in fact
the write was lost when the power failed), then the journal does
not know about the error and the only way to fix it is to run a
full filesystem check.

	Kirk McKusick