On 06/21/2018 10:28 PM, Chris Murphy wrote: > On Thu, Jun 21, 2018 at 3:59 PM, Kyle Marek <psppsn96@xxxxxxxxx> wrote: > >> If it helps, I've only ever used GRUB on GPT when installing to BIOS >> systems. I haven't encountered *any* issues so far. > It was always model specific. Maybe 1/2 dozen models were affected. > https://bugzilla.redhat.com/show_bug.cgi?id=755226 > https://bugzilla.redhat.com/show_bug.cgi?id=754850 > https://bugzilla.redhat.com/show_bug.cgi?id=741120 > > In one case, the firmware won't boot if it doesn't see the active bit > set on a partition in the MBR, and yet the UEFI spec says no partition > should have an active bit set in a PMBR. And the workaround caused > worse problems (blast from the past): > https://bugzilla.redhat.com/show_bug.cgi?id=754850#c8 > https://bugzilla.redhat.com/show_bug.cgi?id=754850#c9 > > > Anyway, there must be some other bug that ultimately caused GPT to be > abandoned, I'm not finding it at the moment though. Interesting. >> There was a lot to digest with the above and the GPT-default-splatting >> part. Just for clarification, are you "completely" opposed to installing >> GPT on BIOS systems by default *until* there is reason to believe that >> the issues described were now-fixed GRUB bugs? > I'm not opposed to someone looking into it. But I'm opposed to just > assuming it's all going to work out OK. And it's not up to me anyway. > > It might qualify as a system wide change, deadline for which is July > 3. The full change is GPT on BIOS by default *and* including ESP and > BIOSBoot partitions by default needs a conversation with > anaconda/blivet folks if they would accept patches to make that happen > in the Fedora 29 timeframe. They need to be asked first, there's no > point in pushing a feature proposal by a July 3 deadline if the > anaconda folks won't merge the change. And you'd need to own the > feature or find someone to own it, and go through the process. > Basically realize what you might very well be counting on, is that > buggy BIOS computers are now too old and this has since been fixed. > But there's no evidence for this one way or another, as far as I know. > For example, Windows 10's installer today in 2018, will only use MBR > on a drive when the computer boots in BIOS mode. So there's maybe not > much external testing for this. I'm not sure what other distros do by > default. That might be a useful data point. I've noticed that Windows 10 does MBR installs on BIOS, as well. I've always found that interesting because I have also found several laptops (I think most of them were HP) where the OEM installed a BIOS bootloader in addition to the EFI bootloader. My guess is that these OEMs see a similar value in being able to boot both BIOS and EFI. > It may be easier to go for just GPT on BIOS by default, for Fedora 29. > If that doesn't blow up, then go for the partition changes in Fedora > 30. That sounds like a fair way to make this manageable. >> Beyond the benefit of being able to boot EFI and GPT by default, there >> is also the benefit of not storing GRUB in the gap before the first MBR >> partition (I think this is *especially* eyebrow raising on the MBR side >> of things), and the benefits of having GPT in general such as a lack of >> a partition limit, backup partition table, and support for drives larger >> than 2 TiB (though it needs to be noted that the partitions that need to >> be accessed with BIOS calls need to exist within the first 2 TiB, or 8 >> GiB for compatibility with really stupid/old BIOSes). > For what it's worth, if the BIOS system has a drive bigger than 2TB, > then GPT is used by default. This has been true since at least Fedora > 17. > > >> Once the GPT-splatting issue is better understood, I really think that >> if GPT-by-default can be considered at all, it should be. >> > Are you gonna own the feature? :-) Maybe Colin Walters finds it > compelling enough to be co-owner? Can I? I'm a bit new to Fedora development (I don't have a FAS account, yet). However, I do care about correcting things like this. I've found Fedora's way of doing boot loader configuration a little strange and confusing compared to other distros. If Fedora is open to contribution by new members, I would be happy to contribute. _______________________________________________ devel mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://getfedora.org/code-of-conduct.html List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/devel@xxxxxxxxxxxxxxxxxxxxxxx/message/ZOZ6C6IZA5Q64JW6XUCREGF657XECWI6/
