Re: PR/52226 CVS commit: src/sys/modules/lua

[Alexander Mihalicyn <alexander%mihalicyn.com@localhost>]

The following reply was made to PR kern/52226; it has been noted by GNATS.

From: Alexander Mihalicyn <alexander%mihalicyn.com@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: PR/52226 CVS commit: src/sys/modules/lua
Date: Sat, 20 May 2017 17:27:00 +0300

 Hello, Dear Marc Balmer,
 
 I checked out variant of fix from CVS. Sorry, but it is fully correct?
 I would like to point that it's very important that in our original
 fix checking of module already loaded in state was between
 luaL_requiref call and md->refcount++. But in our last fix (from CVS)
 we have that check before luaL_requiref. It seems that this may cause
 a problem:
 consider the following example:
 
 ----
 luactl create s1
 luactl load s1 /root/test.lua
 luactl load s1 /root/test.lua
 luactl destroy s1
 
 test.lua:
 systm = require 'systm'
 
 systm.print("hello, kernel world!\n")
 ----
 
 We got a problem because module in second call of luactl load won't
 loaded into lua context. And we got messages:
 hello, kernel world!
 ...and after that error, that print is undefined (or something similar ;)).
 
 Thank you in advance.
 
 Regards, Alex.
 
 On Sat, May 20, 2017 at 11:35 AM, Marc Balmer <mbalmer%netbsd.org@localhost> wrote:
 > The following reply was made to PR kern/52226; it has been noted by GNATS.
 >
 > From: "Marc Balmer" <mbalmer%netbsd.org@localhost>
 > To: gnats-bugs%gnats.NetBSD.org@localhost
 > Cc:
 > Subject: PR/52226 CVS commit: src/sys/modules/lua
 > Date: Sat, 20 May 2017 08:31:13 +0000
 >
 >  Module Name:   src
 >  Committed By:  mbalmer
 >  Date:          Sat May 20 08:31:13 UTC 2017
 >
 >  Modified Files:
 >         src/sys/modules/lua: lua.c
 >
 >  Log Message:
 >  Only load a module if it is not already loaded in a state (much like userland
 >  Lua handles require).
 >  Fixes PR kern/52226.
 >
 >
 >  To generate a diff of this commit:
 >  cvs rdiff -u -r1.21 -r1.22 src/sys/modules/lua/lua.c
 >
 >  Please note that diffs are not public domain; they are subject to the
 >  copyright notices on the relevant files.
 >