Patch-ID# 100357-01
Keywords:SIGIO, async io, signal, sigblock, sigsetmask
Synopsis: SunOS 4.1.1: SIGIO signal for async io fails to pend across NFS
Date: 06-Sept-91
 
SunOS release: 4.1, 4.1.1
 
Topic: network/rpc, LWP 
 
BugId's fixed with this patch: 1066663 

Architectures for which this patch is available: sun3, sun3x, sun4, sun4c

Patches which may conflict with this patch: 

Obsoleted by: SVR4 

Problem Description: 

The problem is a LWP sharing the same proc table with its parent.  The RPC
signal masking running on top of LWP gets out of sync with the user process.
The user process behaves like it is losing signals because of the sigmask 
being changed by the RPC.
The way we fix this is not to change the sigmask in the RPC if it's in
the LWP context.

**** This patch should only be used when the ASYNCHIO and LWP options are set.


INSTALL: 


cp /usr/sys/sun{3,3x,4,4c}/OBJ/clnt_kudp.o /usr/sys/sun{3,3x,4,4c}/OBJ/clnt_kudp.o.FCS

cp sun{3,3x,4,4c}/clnt_kudp.o /usr/sys/sun{3,3x,4,4c}/OBJ/clnt_kudp.o

Regen the kernel and reboot with the new kernel.

     Please Refer to the System and Networking Administration Manual
             section on building and installing a custom kernel.