updated buildroot make procedure to incorporate configs more robustly

.gitignore

@@ -30,5 +30,6 @@ wally-pipelined/linux-testgen/x*
 !wally-pipelined/linux-testgen/linux-testvectors/tvLinker.sh
 wally-pipelined/linux-testgen/buildroot/
 wally-pipelined/linux-testgen/buildroot-image-output
+wally-pipelined/linux-testgen/buildroot-config-src/main.config.old
 wally-pipelined/regression/slack-notifier/slack-webhook-url.txt
 

wally-pipelined/linux-testgen/WALLY-README.txt

@@ -8,31 +8,46 @@ you'll need to build the new Linux image, simulate it, and parse its output,
 as described below.
 
 *To build a new Linux image:
-     1. Git clone the Buildroot repository to ./buildroot.
+     1. Git clone the Buildroot repository to ./buildroot:
+            git clone https://github.com/buildroot/buildroot.git 
         For reference, Wally (*** will) be proven to work on an image built using
         Buildroot when the following was the most recent commit to the Buildroot repo:
             commit 4047e10ed6e20492bae572d4929eaa5d67eed746
             Author: Gwenhael Goavec-Merou <gwenhael.goavec-merou@trabucayre.com>
             Date:   Wed Jun 30 06:27:10 2021 +0200
 
-     2. Then hard link ./buildroot-config-src/main.config to ./buildroot/.config.
+     2. If you wish to modify the configs, then in ./buildroot:
-        That config file will in turn point to the other config files in ./buildroot-config-src.
-
-     3. If you wish to modify the configs, then in ./buildroot:
         a. Run "make menuconfig" or "make linux-menuconfig" or "make busybox-menuconfig".
-        b. For linux-menuconfig and busybox-menuconfig, use the TUI (terminal UI) to load in
+        b. Use the TUI (terminal UI) to load in the existing configs.
-           configs from "../../../../buildroot-config-src/<linux or busybox>.config"
+
-           We have to tell make to go back up several dirs because for linux and busybox,
+           For menuconfig, you can load in the source file from
-           make traverses down to ./buildroot/output/build/<linux or busybox>.
+               "../buildroot-config-src/main.config"
+
+           For linux-menuconfig or busybox-menuconfig, load in from 
+               "../../../../buildroot-config-src/<type>.config"
+           because for linux and busybox, make traverses down to
+                ./buildroot/output/build/<linux or busybox>.
+          
+           One annoying thing about the TUI is that if it has a path already loaded,
+           then before you can enter the new path to buildroot-config-src, you need to
+           delete the existing one from the textbox. Doing so requires more than backspace.
+           Once you've deleted as much of the existing path as you can see, arrow left to 
+           check if there is more text you need to delete.
+
         c. Likewise, when you are done editing, tell the TUI to save to the same location.
 
-     4. Then finally you can run make. Note that it may be necessary to rerun make twice,
+     3. Finally go to ./buildroot-config-src and run make-buildroot.sh.
-        once when main.config asks for an "Image" output, and once when main.config
+        This script copies ./buildroot-config-src/main.config to ./buildroot/.config
-        "vmlinux" output.
+        and then invokes make. This is clumsy but effective because buildroot
+        sometimes does weird things to .config, like moving it to .config.old and 
+        making a new .config -- doing so can really mess up symbolic/hard links.
+
+     4. If you'd like debugging symbols, then reconfigure Buildroot to output "vmlinux"
+        and run make-buildroot again.
 
 *To generate new RAMs and testvectors from a Linux image:
     1. sym link ./buildroot-image-output to either your new image in ./buildroot/output/image 
-       or the existing image at /courses/e190ax/buildroot/output/image on Tera. 
+       or the existing image at /courses/e190ax/buildroot-image-output on Tera. 
        This might require first deleting the empty buildroot-image-output directory.
     2. Then run ./testvector-generation/logBuildrootMem.sh to generate RAMs.
     3. Then run ./testvector-generation/logAllBuildroot.sh to generate testvectors.

wally-pipelined/linux-testgen/buildroot-config-src/make-buildroot.sh

@@ -0,0 +1,3 @@
+cp main.config ../buildroot/.config
+cd ../buildroot
+make