Created attachment 758577 [details]
Truncated end of the dmesg output from System 1

Description of problem:
I've tested the recently added "iso-scan/filename" parameter (by the way thanks for implementing it) with the Fedora 19 Beta and it works fine when the iso file is on the internal harddrive but I have problems using it on a USB thumbdrive.


How reproducible:
Reproducible on 2 of 3 systems (see Actual results)


Steps to Reproduce:
I've used the following grub.cfg entry to boot the Fedora 19 Beta Live iso:

if test -f /boot/iso/Fedora-19-Beta.iso; then
    menuentry 'Fedora 19 Beta' {
        set isofile="/boot/iso/Fedora-19-Beta.iso"
        loopback loop "$isofile"
        set root=(loop)
        linux /isolinux/vmlinuz0 iso-scan/filename=$isofile root=live:LABEL=Fedora-Live-Desktop-x86_64-19-Be ro rd.live.image quiet rhgb rd.luks=0 rd.md=0 rd.dm=0
        initrd /isolinux/initrd0.img
    }
fi


Actual results:
On some systems the live system won't boot and drops to the emergency shell. I've tested it on three systems:

- System 1 boots fine if the iso file is on the internal harddrive but cannot find the iso file if it is on the USB thumbdrive
- System 2 won't boot from the USB thumbdrive
- System 3 successfully boots from the USB thumbdrive


Expected results:
Successful boot of the live system on all systems.


Additional info:
My assumption would be that the iso detection script is executed before the USB drive is recognized.