Bug 9824

I'll try to look at this. Do you remember when they're working last time?

I was able to boot core-image-minimal on my Minnowboard MAX just fine. Will try core-image-sato now.

btw, you saw grub menu because mkefidisk.wks sets grub as a bootloader:
part /boot --source bootimg-efi --sourceparams="loader=grub-efi" --ondisk sda --label msdos --active --align 1024

I think it's always been like that.

I've just built core-image-sato and booted it to the shell. Here is what I see on the console:

Poky (Yocto Project Reference Distro) 2.1+snapshot-20160628 intel-corei7-64 /de0

intel-corei7-64 login: root
root@intel-corei7-64:~# rpm -qa | wc -l
1676
root@intel-corei7-64:~# 

I can't see graphical UI though as I'm using serial console. However, the fact that image is booting to the shell is enough to prove that wic creates bootable image.

Built core-image-sato from revision 6f0c5537e02c59e1c8f3b08f598dc049ff8ee098
It booted to the shell.

I'm using intel-corei7-64 machine. 
I'm going to build the image for genericx86-64 and try again.

Built and booted core-image-minimal genericx86-64
building core-image-sato

built and successfully booted core-image-sato genericx86-64:
Poky (Yocto Project Reference Distro) 2.1+snapshot-20160628 genericx86-64 /dev/ttyS0

genericx86-64 login: root
root@genericx86-64:~#

This image http://10.237.112.85/wic-images/genericx86-64/mkefidisk/core-image-sato/build/mkefidisk-core-image-sato-genericx86-64.direct is definitely broken. An attempt to mount root partition causes mount to fail with this error:
$ sudo mount /dev/sdb2 /mnt/
mount: wrong fs type, bad option, bad superblock on /dev/sdb2,
       missing codepage or helper program, or other error

and this line in dmesg:
[686485.983900] EXT4-fs (sdb2): bad geometry: block count 166400 exceeds size of device (118019 blocks)

The amount of packages in both images(broken AB image and the image i've built) are the same, but the size of rootfs partition image for AB image is much bigger (650Mb vs 462Mb)

Could someone point me out to the ab code that builds wic image?

Can we try to build mkefidisk image on official ab?
This configuration change should be enough to do it I hope:
diff --git a/buildset-config.controller/nightly-wic.conf b/buildset-config.controller/nightly-wic.conf
index 680ac16..7d2ae88 100644
--- a/buildset-config.controller/nightly-wic.conf
+++ b/buildset-config.controller/nightly-wic.conf
@@ -18,7 +18,8 @@ steps: [{'SetDest':{}},
         {'BuildImages':{'images':'syslinux syslinux-native parted-native gptfdisk-native dosfstools-native mtools-native'}},
         {'BuildImages':{'images':'core-image-sato'}},
         {'CreateWicImages':{'wic_img_type':'directdisk', 'target_img':'core-image-sato'}},
-        {'CreateWicImages':{'wic_img_type':'directdisk-gpt', 'target_img':'core-image-sato'}}]
+        {'CreateWicImages':{'wic_img_type':'directdisk-gpt', 'target_img':'core-image-sato'}},
+        {'CreateWicImages':{'wic_img_type':'mkefidisk', 'target_img':'core-image-sato'}}]

I've checked 4 images produced by one of official AB workers and they're good. I'm still not able to reproduce the issue in my environment.

taking this bug as I'm working on it anyway

We worked with Alexandru on this. He created a core-image-sato mkefidisk image and I was able to boot it without changing anything. So, the issue is not reproducible anymore on his machine.

I think I found the real reason for this bug. The .wks file was modified pointing to sdb device. The result of this change is 'root=/dev/sdb2' was added to the kernel command line in bootloader configuration.

I was able to boot the image from http://10.237.112.85/wic-images/genericx86-64/mkefidisk/core-image-sato/build/ after I changed /dev/sdb2 to /dev/sda2.