From: Jeff Kletsky <git-commits@allycomm.com>

Wifi can, in certain situations, cause sysupgrade to fail silently
with a 256 return value as all processes can't be killed.
One of these situations is mesh with batman-adv active.

Added `wifi down` just prior to the killall sequence in stage2

Run-tested-on: Linksys EA8300

Signed-off-by: Jeff Kletsky <git-commits@allycomm.com>
---
package/base-files/files/lib/upgrade/stage2 | 4 ++++
1 file changed, 4 insertions(+)

Index: openwrt/package/base-files/files/lib/upgrade/stage2
===================================================================
--- openwrt.orig/package/base-files/files/lib/upgrade/stage2
+++ openwrt/package/base-files/files/lib/upgrade/stage2
@@ -123,6 +123,10 @@ kill_remaining KILL 1
 
 sleep 1
 
+if [ -x "$(which wifi)" ]; then
+	wifi down
+	sleep 1
+fi
 
 if [ -n "$IMAGE" ] && type 'platform_pre_upgrade' >/dev/null 2>/dev/null; then
 	platform_pre_upgrade "$IMAGE"