YP 1.7. meta-amd. building a custom image recipe based on core-image fails if the rootfs size + initrd size + syslinux boot files + EFI boot files exceeds ~4GB.  The build hangs, with 'ps' showing that mcopy is in a stopped state.  From a user's perspective, the build hangs without any console output.  The last line displayed on the console is "NOTE: recipe <foo>: task do_bootimg: Started"

Log files provide no further useful data.

What's actually happening is that mcopy, with stdin/stdio/stderr redirected to bitbake, is asking for console input (even though the correct mcopy flags are passed to squash any console interaction ;) ) and of course, there is no way for the user to know reply.

mcopy is unable to handle files greater than 4GB anyway, so there isn't really a quick fix here.  live image types, as currently designed, are limited to 4GB images.

I'm pretty sure the hardware platform is irrelevant.  Any image recipe for any target which uses live image types will fail if the rootfs.img + <rest> is greater then 4GB.

I will be submitting a patch to at least bail and warn to prevent a silent hang.