The comment may refer to an UEFI implementation that also check the booted OS name and will only allow Windows or RHEL to boot. It should be simple to work-around that by just adjusting the name. I can't remember where I read about this and can't find (quickly;) a reference though.
Posted Jan 6, 2013 16:39 UTC (Sun) by mjg59 (subscriber, #23239)
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That's got nothing to do with the bootloader used (and isn't related to Secure Boot), so it doesn't seem like it.
LWN's 2013 Predictions
Posted Jan 7, 2013 13:52 UTC (Mon) by pjones (guest, #31722)
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I'm well aware of that issue, and have been in contact with the vendor in question - but as mjg59 said, that's nothing at all to do with secure boot. It's just an unrelated bad idea some firmware vendor had.