I've just tested the patch on a FAT32 wubi install and it worked as intended.
In order to test it, I manually edited the /usr/share/grub/grub- mkconfig_lib file during the installation (patch wasn't installed), used 'diff' to confirm it matched the patch, and then copied it to /target/usr/share/grub/grub_mkconfig_lib (/target/usr is the mount point for /dev/loop4 which is for the usr.disk virtual disk). And root.disk was mounted as /dev/loop2 on /target. The grub.cfg that was generated during the install is attached, and it shows that usr.disk will be mounted on loop4 by grub and root.disk is mounted as loop2: insmod part_msdos insmod fat set root='(hd1,msdos5)' search --no-floppy --fs-uuid --set=root 2dab-fe25 loopback loop4 /ubuntu/disks/usr.disk set root=(loop4) if loadfont /share/grub/unicode.pf2 ; then set gfxmode=auto load_video insmod gfxterm insmod part_msdos insmod fat set root='(hd1,msdos5)' search --no-floppy --fs-uuid --set=root 2dab-fe25 loopback loop2 /ubuntu/disks/root.disk set root=(loop2) set locale_dir=($root)/boot/grub/locale set lang=en_US insmod gettext fi ... After rebooting and selecting the Wubi install, there was no error or return to the menu. Then running "sudo update-grub" resulted in grub.cfg changing the loop device for usr.disk to loop1 and root.disk to loop0 (as expected): insmod part_msdos insmod fat set root='(hd1,msdos5)' search --no-floppy --fs-uuid --set=root 2dab-fe25 loopback loop1 /ubuntu/disks/usr.disk set root=(loop1) if loadfont /share/grub/unicode.pf2 ; then set gfxmode=auto load_video insmod gfxterm insmod part_msdos insmod fat set root='(hd1,msdos5)' search --no-floppy --fs-uuid --set=root 2dab-fe25 loopback loop0 /ubuntu/disks/root.disk set root=(loop0) set locale_dir=($root)/boot/grub/locale set lang=en_US insmod gettext fi ** Attachment added: "Grub generated during the installation (ubiquity)" https://bugs.launchpad.net/wubi/+bug/888281/+attachment/2832360/+files/grub.cfg.at.install -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/888281 Title: Boot from FAT32 error and return to grub menu To manage notifications about this bug go to: https://bugs.launchpad.net/wubi/+bug/888281/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
