Julian Sikorski <belegdol@xxxxxxxxx> writes: > Hi list, > > I recently got curious about unified kernel images and what they bring > to the table. While informing myself about these, the following > questions came to mind: > - ESP partition size: my laptop has it set at 260 MB by the laptop > vendor, my desktop has it at 100 MB. Recommendation is 200 to 500 MB > [0]. This seems too little, given that now the /boot partition on my > desktop is 512 MB full with 3 kernels installed. Or are the UKIs packed > more efficiently? Moreover, resizing ESP is somewhat challenging due to > a parted bug [1][2]. Are there plans to make this more user-friendly > once UKIs become more prevalent? Hey Julian, are you trying 'kernel-uki-virt' package or building your own UKI? With 'kernel-uki-virt' we're mostly targeting virtualized and cloud environments but bare metal can certainly be tried too! The size of the packaged vmlinuz-virt.efi is 68Mb now so if you keep three of them in your ESP, you need 210Mb or so. 256 MB feels limiting but I don't think anything prevents from creating a bigger ESP. I'm not sure about resizing partitions but if you're ready to wipe out your hard drive completely, it should work. > - does UKI work with third-party kernel modules like nvidia? Yes, there's no difference between the traditional kernel layout and UKI if you want to use third party modules. The only issue (not specific to UKI) is SecureBoot. If you want to keep it on, you may need to either enroll your key into SecureBoot 'db' (possible on virtualized and cloud environments) or deal with 'MOK' (the only sane option for bare metal). > - grub-less UKIs mean updating efivars with every kernel update. GRUB > developers expressed concerns this might wear down the NVRAM chips. Was > this ever looked into in more detail? With 'kernel-uki-virt' we're targeting virtualized and cloud environments where NVRAM is virtual so it's not an issue. It may (in theory) represent a problem for certain bare metal scenarios, in that case I would recommend using a bootloader between UEFI and UKI. As grub is not capable of booting UKIs (I remember seeing patches doing this but I'm not sure they were merged upstream/in Fedora) something like systemd-boot can be used. The merging 'nmbl' bootloader should also be capable of booting UKIs from day 1 (AFAIU). (Personally, I'm not sure NVRAM wear is a real world problem. AFAIU, different NVRAMs support 10000 to 500000 write cycles. For example, koji tells we that there were 173 kernel built for Fedora-39. Even 10000 cycles will allow you to use 57 Fedora versions and this is likely beyond the life expectancy of any hardware.) -- Vitaly -- _______________________________________________ devel mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-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/devel@xxxxxxxxxxxxxxxxxxxxxxx Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
