Re: kern/48135: Bad locking for umount

[Michael van Elst <mlelstv%serpens.de@localhost>]

On Thu, Aug 22, 2013 at 10:40:00AM +0000, J. Hannken-Illjes wrote:

>  Btw.: I'm not able to reproduce this error here -- what exactly is
>        your setup (amd configuration etc.)

It's a dual core amd64 machine that mounts an NFS server.

[global]
restart_mounts    = yes
map_type          = file
search_path       = /etc/amd
dismount_interval = 3
cache_duration    = 3
auto_attrcache    = 1
log_options       = all

[ /a ]
map_name      = pussyfoot

and the map:

source \
        -type:=nfs;opts:=rw,nosuid,nodevs,intr,nfsv3,readdirplus,proto=tcp \
        rhost:=fud;rfs:=/d/1

The race condition happens after setting auto_attrcache=1, but it might
have been triggered before.

The "fix" prevents this race, but it surely opens others.


Greetings,
-- 
                                Michael van Elst
Internet: mlelstv%serpens.de@localhost
                                "A potential Snark may lurk in every tree."