On Tue, 12 Jun 2018 14:25:48 +0800 Xi Ruoyao <r...@stu.xidian.edu.cn> wrote:
> efibootmgr uses the library from efivar for /sys/firmware/efi/efivars. > I searched "efivarfs" in the Github repo and found the commit to add > efivarfs support: > https://github.com/rhboot/efivar/commit/5b175a55d53c5d0f44e3636802fc7dc3fe7549a6 Thanks Xi! Yeah, that ability was added already in mid-2013. And so efibootmgr will auto select between efivarfs and the sysfs interface depending on what is available. So, any post-2013 efibootmgr will be able to use either interface. From https://www.kernel.org/doc/Documentation/filesystems/efivarfs.txt. "The efivarfs filesystem was created to address the shortcomings of using entries in sysfs to maintain EFI variables. The old sysfs EFI variables code only supported variables of up to 1024 bytes. This limitation existed in version 0.99 of the EFI specification, but was removed before any full releases. Since variables can now be larger than a single page, sysfs isn't the best interface for this. " So, the EFI spec itself changed and that is why we have the new interface. Mike -- http://lists.linuxfromscratch.org/listinfo/lfs-support FAQ: http://www.linuxfromscratch.org/blfs/faq.html Unsubscribe: See the above information page Do not top post on this list. A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail? http://en.wikipedia.org/wiki/Posting_style
