Subject: kern/11802: m_copym0 overrun on arm26 with NFS root
To: None <>
From: Ben Harris <>
List: netbsd-bugs
Date: 12/23/2000 10:31:15
>Number:         11802
>Category:       kern
>Synopsis:       m_copym0 overrun on arm26 with NFS root
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Dec 23 10:31:00 PST 2000
>Originator:     Ben Harris
>Release:        2000-12-22
NetBSD 1.5P on arm26

On all my arm26 systems, when booting with root on NFS, I get a "m_copym
overrun" panic while init is starting.  This seems to be caused by
nfs_request() dereferencing a null "cred" pointer.  A stack backtrace from
there (where I've planted a KASSERT) upwards goes:


It seems that nfs_writerpc gets the "cred" pointer from the vnode in the
buf on the queue handled by the nfsiod.

Boot an arm26 system with root on NFS.  Works on all three of mine (two
4Mb one 8Mb, all three arm26 Ethernet drivers).