Pat Riehecky wrote: > A new version of nfs-utils (nfs-utils-1.2.3-15.el6.0.sl6) has been > posted in the Scientific Linux testing repository. The only > difference between it and the existing one is an incremented version > number. If testing verifies it works as expected it may be placed in > the security tree. If I upgrade from the (fixed) nfs-utils-1.2.3-15.el6.x86_64 rpm to this version on otherwise up-to-date SL 6.1 x86_64 systems, the umount.nfs segfault issue is back: umount.nfs[18630]: segfault at 19 ip 00007f605615653a sp 00007fffd63705c0 error 4 in libc-2.12.so[7f60560df000+197000] It only seems to occur with NFS mounts served from a RHEL 5.7 x86_64 system. There is no problem with unmounting mounts served from a RHEL 6.1 x86_64 NFS system. This behaviour persists after a reboot. Downgrading back to nfs-utils-1.2.3-15.el6.x86_64 makes the issue go away again.