It is not possible to boot syslinux.efi with recent versions of ovmf. The one provided on tianocore page http://sourceforge.net/projects/edk2/files/OVMF/OVMF-X64-r11337-alpha.zip/download still works though. In order to test installation isos it would be great if this would also work with more enhanced versions of ovmf. As stated on IRC, it is not possible to launch syslinux.efi, the error message from efi shell is just: Unsupported.
Sorry I didn't see this bug report before. I've had the exact same issue and produced a few patches for it. See the following mails on the mailing list: http://www.syslinux.org/archives/2013-November/021203.html http://www.syslinux.org/archives/2013-November/021202.html http://www.syslinux.org/archives/2013-November/021204.html http://www.syslinux.org/archives/2013-November/021200.html http://www.syslinux.org/archives/2013-November/021201.html I made this to work with the git revision of edk2 / OVMF in addition to the git revision of qemu.
Just for information, the last version of those patches is available on my github at: https://github.com/Celelibi/syslinux.git branch fix/efi/elf-to-pe-3 Don't hesitate to give me any feedback.
Syslinux efi64 built from http://git.zytor.com/?p=syslinux/syslinux.git;a=commit;h=9692baed476a71d5225174f8d7bba31bcc0393d1 is able to boot in OVMF X64 compiled from latest Tianocore SVN sources (Arch Linux AUR ovmf-svn pkg). Thank you Celelibi.
This bug should be fixed by the commit 9692bae 9e49e29 0468e14 76ef6aa 8c9a43f, which are available in the release 6.03.