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Fedora considers deprecating legacy BIOS

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Re: Fedora considers deprecating legacy BIOS

#181
In my admittedly limited time using Linux (switched to it full-time in ~2001), the total amount of effort I've spent troubleshooting issues has probably been dominated by two categories:

1. Getting audio to behave.

2. Boot problems. (waves at LILO)

I don't know enough details about how UEFI and BIOS and MBR and GRUB and all of this works -- which probably contributed to my difficulties. But the problems certainly didn't end when I left LILO behind.

So it always makes me wonder: Have the people responsible for the bootloaders ever used a Mac? My goodness it could not be simpler. Hold the right key combo at boot time and you get a nice interface that shows you all the bootable devices you've got plugged in. USB, SATA, NVMe, whatever, it's there. And when you select one and boot, it actually works.

Recognizing that we don't actually need a GUI for this, and the challenge is different because Apple gets to use firmware and only worries about one type of OS, what would it take to make a PC bootloader work just as nicely?

Re: Fedora considers deprecating legacy BIOS

#182

Oh god. So after Windows drops support basically for any PC that is 4 years old, a Linux distribution entertains the idea to follow closely and drop support for any PC that is 10 years old? Is this corporate influence? I cannot believe BIOS boot support is even close to the amount of code required for UEFI boot. Before you say "UEFI is much older than 10 years old", please remember that UEFI only started being a defa…

>a Linux distribution I think it matters quite a lot that the distro in question is Fedora which is by design forward looking and kind of a testbed. They have been shipping Wayland as a default since 2016 when it still had countless of hardware and software problems. Part of the diversity of the linux ecosystem is that distros can be opinionated.

Wayland! Ye gods. I tried. I really did. I understand that from a developer standpoint, it's the future. I understand from a security standpoint, it's more secure. From a user standpoint? It completely breaks so much functionality (copy / paste, screen share, blue light filters, etc). Video players crash and sometimes take down the whole OS with it. It puts so much responsibility that used to be the job of the x server off on the window managers.

This shift to wayland has been one of the most user hostile decisions I've seen. Every distro that defaults to wayland pushes me that much closer to simply running linux in a WSL container on windows.

Re: Fedora considers deprecating legacy BIOS

#183
post #25

Earlier quoted context omitted.

- previously, x86 MBR-style partition tables (which were the only thing really supported in Linux) gave you no strong semantic information about what a partition was[1]. GPT may involve GUIDs, but in the grand scheme of things that's a small part of the cost of mounting stuff. - FAT is old, and FAT is well-supported by basically anything, and what features do you want in the partition that contains your bootloader th…

> what features do you want in the partition that contains your bootloader that FAT doesn't support? Well, I'd love to be able to drop a bunch of 8GB (notably FAT doesn't support files this big) LiveDVD disk images on a bare file system and see them in the computer's built-in boot-menu immediately. I already enjoy the fact I don't need a traditional boot loader (like GRUB) to handle multi-OS as I can have 2 independe…

The first and only instruction that runs is on the “read-only” boot image which can be the whole OS. The solid state image is read-only because the tab is physically in the read-only position. The is the entire specification for booting.

Re: Fedora considers deprecating legacy BIOS

#184
post #12

Earlier quoted context omitted.

What replacement do you propose, then? Especially what replacement do you propose that works with the kind of typical hardware that non-specialty linux distros like Fedora want to support? Intel systems make up a large chunk of the hardware Fedora is used on, and as far as I can tell they're all-in on EFI. So Fedora has to use EFI to be able to boot on Intel systems.

I have encountered various embedded computers which no longer have the legacy BIOS boot option, so using EFI is indeed necessary. However, the vast majority of server or desktop motherboards and of laptops still have the option for legacy BIOS booting, even if the option may be difficult to find in the BIOS menus. I have about a dozen servers, desktops and laptops and I have configured all of them to use legacy BIOS…

>because EFI booting does not have any advantage, only disadvantage

For an already installed system it doesn't really matters, so the point is moot here.

But for the new systems setup I would always prefer a UEFI (with or without SecureBoot) because it allows to expose the HID management of the onboard/expansion board controllers, a proper way to return to the management/boot menu in the case of the failed boot.

Sure, it doesn't always work good, but neither BIOS/CMS.

Re: Fedora considers deprecating legacy BIOS

#185

Earlier quoted context omitted.

But ExFAT lacks the FAT's virtues of being universally supported and royalty-free, yet still is a very dumb FS with no journal (which means unreliable) and no extended attributes (which means data-metadata separation impossible) so I don't see a reason for it to exist anywhere outside severely resource-limited embedded applications. I would rather use Ext4 everywhere for everything. Is the problem preventing wide ado…

Seemly ExFAT is specially unreliable... Nintendo Switch community first advice when you buy one is: If you buy a SD Card with ExFAT, reformat it to FAT, because ExFAT will eventually cause your files to be corrupted...

The Switch has a bad exfat driver.

Re: Fedora considers deprecating legacy BIOS

#186
post #90

Earlier quoted context omitted.

I believe that btrfs can be whole-disk and avoid partitions entirely, which would drastically simplify things. The only snag is swap, which I don't believe can be on a subvolume. vgchange is a struggle for me, from the first time I saw it in HP-UX.

> The only snag is swap, which I don't believe can be on a subvolume. Linux can make swap a regular file, even. It doesn't need to be a partition. Google result shows: https://wiki.archlinux.org/title/swap#Swap_file

until kernel 5.0 swap files were not supported on btrfs.

there's also some limitations, see https://btrfs.readthedocs.io/en/latest/btrfs-man5.html#swapf...

Re: Fedora considers deprecating legacy BIOS

#188

Earlier quoted context omitted.

I have a UEFI system right here under my desk that provides legacy BIOS services for running option ROMs, video cards, SCSI host bus adapters, network adapters, anything. It even scans out their legacy video outputs in a little window. There's nothing incompatible between UEFI and legacy option ROMs. Perhaps you are thinking of Secure Boot.

>Perhaps you are thinking of Secure Boot. Nope. I think there must be a miscommunication here so I'll be more explicit. If you have CSM/BIOS mode on your UEFI default motherboard and you set it to CMB/BIOS mode of course you can run BIOS based video cards. But if you switch your mobo to UEFI boot (say, because you want to run future Fedora, or maybe boot off an nvme storage device) you can't use your BIOS firmware vi…

A lot of firmware supports using CSM to do GPU init and then providing UEFI interfaces on top of that. Of course, this is incompatible with Secure Boot.

Re: Fedora considers deprecating legacy BIOS

#189

Earlier quoted context omitted.

>a Linux distribution I think it matters quite a lot that the distro in question is Fedora which is by design forward looking and kind of a testbed. They have been shipping Wayland as a default since 2016 when it still had countless of hardware and software problems. Part of the diversity of the linux ecosystem is that distros can be opinionated.

Wayland! Ye gods. I tried. I really did. I understand that from a developer standpoint, it's the future. I understand from a security standpoint, it's more secure. From a user standpoint? It completely breaks so much functionality (copy / paste, screen share, blue light filters, etc). Video players crash and sometimes take down the whole OS with it. It puts so much responsibility that used to be the job of the x serv…

Wayland has changed since you last tried. I haven't got copy paste or blue light issues with it since Fedora 35 went with Wayland-by-default. Screen share is iffy on Electron, but that behemoth is slow to pick up new technologies.

I don't know about video players crashing either.

When talking about a fast moving new piece of technology, it's good to give it a try once in a while and not let your 4 year old experience colour your judgement.

Re: Fedora considers deprecating legacy BIOS

#190
post #32

UEFI emulation is a thing. For people with legacy-only firmware systems, you too can run UEFI on lazy cloud providers and legacy hardware. I do this on my 14 year old dell laptop just so that all my x86_64 systems have the same boot efistub linux kernel images. All you need is to use one of the EDK DUET bootloader builds such as BootDuet¹, or for an easier user experience CloverBootloader². Only complaint is securebo…

Interesting... I'll check if it can emulate 64 bits UEFI on a 32 bits one (yet 64 bits cpu): Finding anything to boot on my old tablet PC is becoming a pain.
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