From 15d8e03c3208cd61069f54f3776796a87a002001 Mon Sep 17 00:00:00 2001
From: Kyle Evans <kevans@FreeBSD.org>
Date: Sun, 18 Feb 2018 00:56:12 +0000
Subject: [PATCH] stand/lua: Fix module_path handling with multiple kernels

Once we've successfully loaded a kernel, we add its directory to
module_path. If we switch kernels with the kernel selector, we again prepend
the kernel directory to the current module_path and end up with multiple
kernel paths, potentially with mismatched kernel/modules, added to
module_path.

Fix it by caching module_path at load() time and using the cached version
whenever we load a new kernel.
---
 stand/lua/config.lua | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/stand/lua/config.lua b/stand/lua/config.lua
index 34f7f7421a49..82372b14ebef 100644
--- a/stand/lua/config.lua
+++ b/stand/lua/config.lua
@@ -115,6 +115,7 @@ local pattern_table = {
 	[10] = {
 		str = "^%s*([%w%p]+)%s*=%s*\"([%w%s%p]-)\"%s*(.*)",
 		process = function(k, v)
+			print("Setting '"..k.."' to '"..v.."'")
 			if loader.setenv(k, v) ~= 0 then
 				print("Failed to set '"..k.."' with value: "..v.."");
 			end
@@ -124,6 +125,7 @@ local pattern_table = {
 	[11] = {
 		str = "^%s*([%w%p]+)%s*=%s*(%d+)%s*(.*)",
 		process = function(k, v)
+			print("Setting '"..k.."' to '"..v.."'")
 			if loader.setenv(k, v) ~= 0 then
 				print("Failed to set '"..k.."' with value: "..v.."");
 			end
@@ -293,7 +295,9 @@ function config.loadkernel(other_kernel)
 			return false;
 		end
 	else
-		local module_path = loader.getenv("module_path");
+		-- Use our cached module_path, so we don't end up with multiple
+		-- automatically added kernel paths to our final module_path
+		local module_path = config.module_path;
 		local res = nil;
 
 		if other_kernel ~= nil then
@@ -308,9 +312,9 @@ function config.loadkernel(other_kernel)
 			loader.setenv("module_path", v);
 			res = load_bootfile();
 
-			-- succeeded add path to module_path
+			-- succeeded, add path to module_path
 			if res ~= nil then
-				if module_path ~= nil then
+				if (module_path ~= nil) then
 					loader.setenv("module_path", v..";"..
 					    module_path);
 				end
@@ -350,6 +354,9 @@ function config.load(file)
 		end
 	end
 
+	-- Cache the provided module_path at load time for later use
+	config.module_path = loader.getenv("module_path");
+
 	print("Loading kernel...");
 	config.loadkernel();