livepatch: improve rune for fetching of Build ID

The current one is broken with my version of readelf and returns
'NT_GNU_BUILD_ID'.

Signed-off-by: Roger Pau Monné <roger.pau@citrrix.com>
Reviewed-by: Bjoern Doebel <doebel@amazon.de>
Reviewed-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>

diff --git a/README.md b/README.md
index b48a3dfd6edad7c767c49df3cfe855c55284325d..948a7de260efebdf11f3c358a52ee317c130c5e1 100644 (file)
--- a/README.md
+++ b/README.md
@@ -16,7 +16,7 @@ $ cp -r ~/src/xen ~/src/xenbuild
 $ cd ~/src/xen/xen
 $ make nconfig # Make sure to set CONFIG_LIVEPATCH=y
 $ make
-$ BUILDID=$(readelf -Wn xen-syms | awk '/Build ID:/ {print $3}')
+$ BUILDID=$(readelf -Wn xen-syms | sed -n -e 's/^.*Build ID: //p')
 ```
 
 Next, build a live patch, using a patch and the source, build ID, and