Major issues with nfsv4

[J David]

On Fri, Dec 11, 2020 at 6:08 PM Alan Somers <asomers at freebsd.org> wrote:
> That's some good information.  However, it must not be the whole story.

Indeed not.  If it were, this would happen instantly every time.
There must be some sort of trigger.  But there are a lot of jobs that
run and I didn't write any of them.  So the search space is large.

> Are you using any mount options with nullfs?

nosuid and, on half the mounts, ro.

> It might be worth trying to make the read-only mount into read-write, to see if that helps.

It won't; the read-only mounts they are exported read-only on the
server side.  And no one is going to sign off on changing that, not
even for a minute.

> And what does "jls -n" show?

Here is an example, newlines added for readability:

devfs_ruleset=0
nodying
enforce_statfs=2
host=new
ip4=disable
ip6=disable
jid=1020
linux=new
name=job-1020
osreldate=1202000
osrelease=12.2-RELEASE
parent=0
path=/job/roots/job-1020
persist
securelevel=-1
sysvmsg=inherit
sysvsem=inherit
sysvshm=inherit
vnet=inherit
allow.nochflags
allow.nomlock
allow.nomount
allow.mount.nodevfs
allow.mount.nofdescfs
allow.mount.nofusefs
allow.mount.nonullfs
allow.mount.noprocfs
allow.mount.notmpfs
allow.noquotas
allow.noraw_sockets
allow.noread_msgbuf
allow.reserved_ports
allow.set_hostname
allow.nosocket_af
allow.sysvipc
children.cur=0
children.max=0
cpuset.id=87
host.domainname=/""}""
host.hostid=0
host.hostname=job1020.local
host.hostuuid=00000000-0000-0000-0000-000000000000
ip4.addr=10.0.3.252
ip4.saddrsel
ip6.addr=2001:db8::1
ip6.saddrsel
linux.osname=Linux
linux.osrelease=3.2.0
linux.oss_version=198144

Seems like the next step is to find a reproduction that doesn't
involve people calling me asking angry questions about why things are
broken again.

Thanks!