[Bug 1201978] dracut assumes BIOS time is UTC closed without fixing again

[Lennart Poettering]

On Tue, 28.04.15 14:50, Michael Schwendt (mschwendt at gmail.com) wrote:

> On Fri, 24 Apr 2015 05:14:27 -0400, Felix Miata wrote:
> 
> > Why does this bug exist only in Fedora, not in openSUSE or Mageia or *buntu?
> > All my systems are multiboot, so only a select very few are on UTC. None that
> > are on UTC have Fedora installed. This means every Fedora boot takes about
> > twice as long or longer than anything else takes, waiting on all the
> > unnecessary FS checks.
> 
> Me too. It's on my growing list of breakage to observe. Haven't spent any
> time on it yet. Logical volumes getting checked nearly at every reboot.
> 
> journalctl shows entries which are two hours in the future at boot time,
> then it returns to the correct time afterwards. I remember there have
> been issues like that years ago - I don't think I've had to do anything
> special to work around it, but perhaps I'm wrong and need to search in
> my notes. Currently, it's broken again.

Fedora doesn't use time-based fsck for a reason, the concept is simply
broken.

UEFI doesn't solve anything with the rtc-in-local stuff windows is
doing there. 

rtc-in-local is really broken but that's hardly Linux' fault, that's
windows' fault. it is inherently incompatible with multi-boot setups,
since the algorithm to adjust for DST requires knowing whether the RTC
was already set to DST or not, and that is saved by windows on the
windows partition, and linux does not have generic access to
that. also, if you'd do multiboot with multiple windows versions this
breaks even on windows, since each windows version stores that flag on
their own partition.

It's a simple fact that rtc-in-local is broken, there is no way around
that, and we cannot support this in linux in full since not even
windows supports in in full...

we do offer a minimal somehwat compatible mode for linux, in which
case DST adjustments don#t work and early boot doesn't get the right
time, but that's exactly how much you will get, and we are willing to
support.

And yes, I am sorry that MS-DOS and Windows cannot handle this, but
that's something to fix in DOS and Windows, because we simply *cannot*
fix this fully on Linux.

And asking for rtc-in-local together with time-based fsck is something
we simply cannot support at all. Either get your RTC set to UTC like
everybody else, or disable time-based fsck like everybody else, but
if you enable both then you are purely on your own.

Essentially you are asking us to support multi-boot with windows, but
you ignore that it's windows that doesn't support it in the first
place...

And no, this *never* worked fully on Linux, and it never will, sorry.

Lennart

-- 
Lennart Poettering, Red Hat