re: kern/50430: syscall_disestablish() can remove active syscalls

[christos%zoulas.com@localhost (Christos Zoulas)]

The following reply was made to PR kern/50430; it has been noted by GNATS.

From: christos%zoulas.com@localhost (Christos Zoulas)
To: gnats-bugs%NetBSD.org@localhost, kern-bug-people%netbsd.org@localhost, 
	gnats-admin%netbsd.org@localhost, netbsd-bugs%netbsd.org@localhost, paul%whooppee.com@localhost
Cc: 
Subject: re: kern/50430: syscall_disestablish() can remove active syscalls
Date: Sun, 15 Nov 2015 16:45:37 -0500

 On Nov 15,  8:25pm, mrg%eterna.com.au@localhost (matthew green) wrote:
 -- Subject: re: kern/50430: syscall_disestablish() can remove active syscalls
 
 |  until bug is fixed, can we disable the autounload?
 
 Sure, that sounds prudent. It is difficult to fix properly. One way to do
 this would be to mark all lwps that have used compat syscalls with a bit
 depending on the module they have used, and refuse to unload the module
 until the lwp is gone.
 
 - when load a module that has compat syscalls, assign to it a bit.
 - mark a flags field of all syscalls that were loaded with that module
   with that bit.
 - or the lwp flags with the syscall flags on each syscall.
 - when it is time to unload check that no lwp has that bit in the flags set.
 - instead of keeping l_sysent, keep l_sysmodflags or something.
 
 christos