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Operating Systems Linux

Lenovo UEFI Bug Only Likes Windows and RHEL 162

New submitter Nagilum23 writes "It looks like Lenovo only knows of Windows and RHEL where their Thinkcentre M92p desktop is concerned. While investigating UEFI boot issues, Matthew Garrett found the PC's firmware actually checks the descriptive string for the operating system, and will prevent unlisted operating systems from booting. Garrett writes, 'Every UEFI boot entry has a descriptive string. This is used by the firmware when it's presenting a menu to users - instead of "Hard drive 0" and "USB drive 3", the firmware can list "Windows Boot Manager" and "Fedora Linux". There's no reason at all for the firmware to be parsing these strings. ... there is a function that compares the descriptive string against "Windows Boot Manager" and appears to return an error if it doesn't match. What's stranger is that it also checks for "Red Hat Enterprise Linux" and lets that one work as well. ... This is, obviously, bizarre. A vendor appears to have actually written additional code to check whether an OS claims to be Windows before it'll let it boot. Someone then presumably tested booting RHEL on it and discovered that it didn't work. Rather than take out that check, they then addded another check to let RHEL boot as well." Note that this isn't a SecureBoot issue. Lenovo is aware of the problem and looking into it.
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Lenovo UEFI Bug Only Likes Windows and RHEL

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  • Well... (Score:2, Informative)

    by Anonymous Coward on Friday November 16, 2012 @10:37AM (#42001005)

    Never ascribe to malice what can be explained by Microsoft getting desperate.

  • Re:That's just great (Score:5, Informative)

    by ledow ( 319597 ) on Friday November 16, 2012 @10:48AM (#42001103) Homepage

    It's nothing to do with Secure Boot, just dodgy BIOS-writing again.

    From TFS: "There's no reason at all for the firmware to be parsing these strings."

    This is basically on a par with Windows 3.1 looking for MS-DOS signatures and refusing to boot otherwise (though that had an illegally anticompetitive reason), with BIOS's like the one I just forced an update from my supplier for (by threatening to return a significant number of laptops) which consisted of a BIOS checking for a certain value on disk being 00 before it would boot from that disk (a value which corresponds to 00 only on unencrypted Windows NTFS-formatted disks) and refusing to boot Truecrypt'd disks or anything with a non-NTFS primary partition (very common on certain HP and Dell models, that particular "bug"), and the like of which I've seen DOZENS of times in my own purchases because of:


    There is no reason to ever test that string, and certainly none to use it as a conditional to boot. It has nothing to do with any advertised UEFI feature whatsoever. The fact that the UEFI code even bothers to interrogate that string for anything other than displaying it to the user tells you that the manufacturer doesn't care about, and doesn't test, anything but Windows to the point they will hard-core their machines to only run Windows. They don't care about UEFI at all, or secure booting, or anything - just that it works when they run Windows.

    Makes you kinda wonder who would ultimately be behind putting such an unnecessary and counter-productive decision into a machine's BIOS really.

  • by Cassini2 ( 956052 ) on Friday November 16, 2012 @11:30AM (#42001523)
  • by ArhcAngel ( 247594 ) on Friday November 16, 2012 @12:02PM (#42001933)
    As a user of ThinkPads for nearly as long I have a TP I cannot install a miniPCI wireless upgrade into without hacking my system because it is not an approved part for my specific ThinkPad. [] Even a miniPCI from another ThinkPad won't always work.
  • by X0563511 ( 793323 ) on Friday November 16, 2012 @01:07PM (#42002763) Homepage Journal

    There is a reason for this:

    The mini-PCI card is just the radio. The antenna is in the rest of the laptop (usually around the screen). The FCC only certifies them for certain radio+antenna pairings, and so they cannot get certification if they don't put in some mechanism to stop you from using uncertified pairings.

    It's stupid yes, but the idea behind the policy is to allow the sale of high-power radios while keeping it within exposure limits. (the reason being is the same power going into an omnidirectional antenna safely can not only exceed but blow-out-of-the-water the exposure limits if put into a directional antenna. think bulb vs laser)

  • Re:TPM is the worst (Score:4, Informative)

    by Minwee ( 522556 ) <> on Friday November 16, 2012 @02:11PM (#42003323) Homepage

    Like how GM and Ford have locked-out the ability to replace the factory-approved air filter with a K&N, because they don't want to "warranty and support" the aftermarket parts!

    *cough* And we know they never tried anything like that because if they had, then there would be something like a Magnuson-Moss Warranty Act [], which would clearly state that companies like GM and Ford could not prevent customers from using aftermarket parts [].

    Stupid prick.

    There's no need to sign your post at the end. We can all see who you are by looking at the header.