deadlock on ZFS during concurrent rename and mkdir
wget https://www.netbsd.org/~riastradh/tmp/dirconc.c cc -pthread -o dirconc dirconc.c mkdir foo dirconc ~/foo > /dev/null
Hangs a 2 core vm for me.
The system is
SunOS omniosce 5.11 omnios-r151034-0d278a0cc5 i86pc i386 i86pcso not the freshest possible, but I can't update right now. However, I do suspect it is readily reproducible by other people.
Does not run into anything on tmpfs presumably thanks to mount point-wide rename lock employed there.
As a data point, it does NOT reproduce on FreeBSD HEAD (running OpenZFS). I have not tried older version.