On 12/21/22 12:17, Lennart Poettering wrote: > On Mi, 21.12.22 12:12, Demi Marie Obenour (demioben...@gmail.com) wrote: > >>> At least for the systemd stuff, we carefully made sure that our access >>> patterns to the ESP both from sd-boot/sd-stub and from userspace are >>> by default as minimal and robust as we can make them, to minimize >>> chance of corruption, given that vfat is not particularly good with >>> that. (i.e. we sync a lot, and the whole ESP mount is by default an >>> autofs instance with an extremely short idle timeout so that it >>> basically remains unmounted — and thus — clean during almost all >>> times). >>> >>> Anyway, if you want to know more about choice of the fs for /boot/, >>> see my ideas here: >>> >>> https://0pointer.net/blog/linux-boot-partitions.html >>> >>> Lennart >> >> Does vfat support atomic rename? Is it possible to atomically upgrade >> a bootloader/UKI/etc? > > Depends on the fs driver. But yeah, the filename is stored at exactly > one place, and hence typically a single-sector update is > possible. (well, within bounds: for example if you rename a file from > a short filename to a long one, fs driver might need to allocate a > bunch of separate long file name dir entries, which might then span > multiple sectors) > > Lennart
Under what circumstances do the Linux kernel driver and the firmware driver actually make such guarantees? For instance, is renaming a file with a longer name to a shorter name (and replacing the old one) atomic? -- Sincerely, Demi Marie Obenour (she/her/hers) _______________________________________________ devel mailing list -- devel@lists.fedoraproject.org To unsubscribe send an email to devel-le...@lists.fedoraproject.org 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@lists.fedoraproject.org Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
