kern/40491: 5.0: nfs timer can crash/break on smp

[ad%netbsd.org@localhost]

>Number:         40491
>Category:       kern
>Synopsis:       5.0: nfs timer can crash/break on smp
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Jan 26 23:55:00 +0000 2009
>Originator:     Andrew Doran
>Release:        5.0_BETA
>Organization:
The NetBSD Project
>Environment:
n/a
>Description:
pooka found a problem with the nfs timer.

solock() can block, and the request being processed can be freed
or change state.


>How-To-Repeat:
Use nfs client, be unlucky.

>Fix:
A cheap and cheerful fix for 5.0 is to comment out the solock/sounlock,
and grab softnet_lock around the whole block.