Jeffrey Walton: >> ++. The firmware on my old Asus Q500a laptop wanted the efi filename >> in all lowercase -- EFI/BOOT/bootx64.efi instead of >> EFI/BOOT/BOOTx64.efi. The laptop would not boot to the DVD otherwise. >> The UEFI on the laptop was by a company called Aptio. On Thu, 2024-07-11 at 10:34 -0400, John Westerdale wrote: > Thought that entries in a vfat file system are case sensitive? I think the issue with Jeffrey's laptop was that its firmware wanted a specific case (when it possibly shouldn't). Or, perhaps Linux shouldn't be using such filenames, and has simply gotten away with it on hardware that didn't care? Though I see some reference to a UEFI spec that says the filename should be "BOOTx64.EFI" (yet another permutation). You can have case-preserving filesystems, and case-ignoring filesystems. And the OS that uses that filesystem can do likewise (take what it gets, ignore what's there and do what it likes, treat UPPER and lower as the same, or treat them differently). On the old DOS, whatever filename you typed was treated as UPPER case. Later OSs might have shown it that way when listing contents, or could show it as lower case. Then later OSs played games with dual filenames for the same file. It was a hideous mess to deal with. Supposedly EFI uses a filesystem that's *based* on FAT but isn't actually FAT - and without any defining specification of what it actually is (therein lays fun and games). FAT is (allegedly) case insensitive and stores all filenames as UPPERCASE (which is odd, 7-bit ASCII has upper and lower case). In any case (pun intended), whatever reads a FAT filesystem may show the filenames as they are, or mangle them. More fun ensues if you create "FILENAME" and "filename" on a file system that can store them as two different files, but then read them with an OS that treats "FILENAME" and "filename" as being the same thing. How does it read the right file? The two files may actually have different contents. Since the behaviour isn't particularly known (there's a myriad of motherboard manufacturers), and there is no true advantage in being able to have two separate and different BOOTx64.efi and bootx64.efi files (any arguments for *needing* that are idiotic - if you need two different boot files, then name them VERY differently), though there is an argument for it being simpler coding to treat such filenames as separate but that is not an argument for being able to create "FILE" and "file" as a useful thing, it'd be sensible if UEFI didn't care for the filename casing. But that's out of our control, because the one thing that would care, the motherboard's firmware, is made by other people. It'd be simpler if the UEFI spec said name it this way and the motherboard's UEFI just looked for one filename. But whatever a spec may say about it, you'll probably find some manufacturer's firmware does something else. Short answer: we're stuffed! -- uname -rsvp Linux 3.10.0-1160.119.1.el7.x86_64 #1 SMP Tue Jun 4 14:43:51 UTC 2024 x86_64 Boilerplate: All unexpected mail to my mailbox is automatically deleted. I will only get to see the messages that are posted to the mailing list. -- _______________________________________________ users mailing list -- users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to users-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@xxxxxxxxxxxxxxxxxxxxxxx Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
