3 ms·
Right. I think it exchanged problems we know, for problems we don't know. And now we're learning about those problems. Or re-learning. With respect to NVRAM bo
by cmurf 9y ago
Right. I think it exchanged problems we know, for problems we don't know. And now we're learning about those problems. Or re-learning.
With respect to NVRAM boot entries, Apple has been doing this for ~30 years and across all of that hardware (three CPU architectures, at least three firmware and three or four filesystems) they have a single method of resetting the NVRAM called "zapping the PRAM" with command+option/apple+p+r at the boot chime. And that's because they know these entries can become corrupt for various reasons. And yet in 2018, what single uniform method exists for clearing stale or corrupt NVRAM information on non-Apple hardware?
Apple also long ago inserted a hint for likely boot device suspects into the HFS volume header, as a fallback for NVRAM in case it was incorrect or had been reset with zapping the PRAM.
With respect to the EFI System partition, Windows and all versions of OS X/macOS do not keep it persistently mounted. That volume is mounted on demand only during updates that require the contents of the volume to be updated, i.e. the bootloader and its files, and is then unmounted. I've always thought this was an incredibly risky as well as lazy thing on all common Linux distros that the EFI system partition is persistently kept rw mounted at /boot/efi.
Somewhat related is when /boot is a separate file system from root, it is also persistently mounted rw on Linux distros. The functional equivalents on Windows and macOS are not persistently mounted. I think it's a rather sloppy practice, but pretty much no one else seems to think it's a problem. You get a crash, and the dirty bits are ignored by read-only firmware and bootloader, so chances are it still boots, and then the dirty bit and any corruptions due to the crash are fixed by fsck during startup. shrug