Merge ~xnox/casper:papercuts into casper:master

[Dimitri John Ledkov]

Fix a bunch of UX papercuts when trying to use VLAN static IP configuration.

1) Sorts interface names
2) Correctly export IP= after $DEVICE got converted into $DEVICE.vlanid
3) Set netmask => default netmask that ipconfig guesses is plain wrong
4) Drop bogus mount - move /cow /root/cow => it doesn't work with tmpfs
5) Break out of the loop waiting for devices to appear quicker, if there are no more udev events

With this in place, I can relatively painlessly configure interactively static IP configuration.

[Michael Hudson-Doyle (mwhudson)]

This all looks good, just one question.

[Michael Hudson-Doyle (mwhudson)]

Oh and while you're here (sorry) have you ever thought about making uuid mismatches noisier? I get extremely confused every time my test vm doesn't boot because I forgot about uuids.

[Dimitri John Ledkov (xnox)]

On Wed, 27 May 2020 at 03:03, Michael Hudson-Doyle
<email address hidden> wrote:
>
> This all looks good, just one question.
>
> Diff comments:
>
> > diff --git a/scripts/casper b/scripts/casper
> > index 6e9ff35..6cecb79 100644
> > --- a/scripts/casper
> > +++ b/scripts/casper
> > @@ -885,6 +890,10 @@ mountroot() {
> > if [ "${livefs_root}" ]; then
> > break
> > fi
> > + # No more udev events, no more devices, nothing to wait for
>
> Are we just waiting for udev here? I thought the issue was that sometimes it takes some time for hardware to show up at all. If I'm mistaken, +1 for sure.
>

I don't know how to make a distinction between hardware that is slow
and we are enumerating 1000s of hard drives looking for our CDROM,
versus interactive netboot where there will never be a drive matching
for us.

My assumption here is that, if we are enumerating 1000s of hard
drives, udev queue will be full of unprocessed events.

On the s390x LPAR, it appears that the installer is hung up, one hits
enter a few times, and then none of the `read -p` work, cause stdin is
full of things.

Whereas on s390x QEMU, the CDROM should appear there quite quickly.

Regards,

Dimitri.

[Dimitri John Ledkov (xnox)]

On Wed, 27 May 2020 at 03:04, Michael Hudson-Doyle
<email address hidden> wrote:
>
> Oh and while you're here (sorry) have you ever thought about making uuid mismatches noisier? I get extremely confused every time my test vm doesn't boot because I forgot about uuids.

That is https://bugs.launchpad.net/ubuntu/+source/casper/+bug/1877618

--
Regards,

Dimitri.

diff --git a/scripts/casper b/scripts/casper
index 6e9ff35..6cecb79 100644
--- a/scripts/casper
+++ b/scripts/casper
@@ -345,7 +345,7 @@ do_interactive_netmount() {
     read -p "vlan id (optional): " vlanid
 
     # pick interface
-    interfaces=$(ls /sys/class/net | grep -v lo)
+    interfaces=$(ls /sys/class/net | grep -v lo | sort)
     count=$(echo $interfaces | wc -w)
     default_device=$(echo ${interfaces} | cut -d " " -f1)
     if [ "$count" -gt 1 ]; then
@@ -359,10 +359,6 @@ do_interactive_netmount() {
         fi
     fi
 
-    if [ "$proto" = "none" ]; then
-       export IP=:$ipaddr:$gateway:::$DEVICE:$proto:$dns
-    fi
-
     . /etc/os-release
     # TODO: not sure how to get flavour information
     # maybe make livecd-rootfs embed something in the casper initrd?
@@ -406,7 +402,19 @@ do_interactive_netmount() {
     if [ -n "$vlanid" ]; then
         export VLAN=$DEVICE.$vlanid:$DEVICE
         DEVICE=$DEVICE.$vlanid
-        export VLAN=$vlan
+    fi
+
+    if [ "$proto" = "none" ]; then
+        case $ipaddr in
+            *.*)
+                netmask=255.255.255.0
+                ;;
+            *:*)
+                # I don't think we support static ipv6
+                netmask=
+                ;;
+        esac
+        export IP=$ipaddr::$gateway:$netmask::$DEVICE:$proto:$dns
     fi
 
     echo Configuring networking...
@@ -703,9 +711,6 @@ setup_overlay() {
         mount -o move "${d}" "${rootmnt}/rofs"
         break
     done
-
-    # move /cow such that live-system can poke & debug the overlayfs layers
-    mount -o move /cow "${rootmnt}/cow"
 }
 
 check_dev ()
@@ -885,6 +890,10 @@ mountroot() {
             if [ "${livefs_root}" ]; then
                 break
             fi
+            # No more udev events, no more devices, nothing to wait for
+            if udevadm settle --timeout 0 2>/dev/null; then
+                break
+            fi
             sleep 1
             i="$(($i + 1))"
         done