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

[Zbigniew Jędrzejewski-Szmek]

On Sun, May 03, 2015 at 03:55:38PM +0200, Lennart Poettering wrote:
> On Sat, 02.05.15 18:03, Zbigniew Jędrzejewski-Szmek (zbyszek at in.waw.pl) wrote:
> 
> > On Tue, Apr 28, 2015 at 02:21:48PM +0200, Ahmad Samir wrote:
> > > On 28 April 2015 at 13:40, Kamil Paral <kparal at redhat.com> wrote:
> > > 
> > > > > On Sun, Apr 26, 2015 at 11:47:18PM -0600, Chris Murphy wrote:
> > > > > > Time in UTC is just as absurd and arbitrary as time in a local
> > > > > > timezone,
> > > > > No, it's not. This has been written about many times, but in short:
> > > > > - the information about the timezone used is not stored in RTC,
> > > > >   so all users of RTC need to be configured to use the same timezone
> > > > >   externally
> > > >
> > > > It surprises me that we see these issues even with UEFI, which seems to
> > > > include support for timezone and DST information [1]. I can confirm this
> > > > myself, I have UEFI with Fedora 21 and Win7 at home, and I noticed that
> > > > there seems to be a fsck running on every Fedora boot. I haven't had time
> > > > to debug it properly yet, but it doesn't seem to work properly out of the
> > > > box. Moreover, if I look into `journalctl -b`, I see time shifted during
> > > > the boot process (which kind of messes up the history whenever I search in
> > > > it). I haven't reported any bug yet, but there's certainly something not
> > > > working out of the box there.
> > > >
> > > >
> > > This is the bug that started this thread:
> > > https://bugzilla.redhat.com/show_bug.cgi?id=1201978
> > This not the right bug.
> > 
> > The problem is a combination of two bugs:
> > https://bugzilla.redhat.com/show_bug.cgi?id=1202024 is about fsck.ext4
> > running full check when the date was off by less then 24h. I is now
> > changed to only print a warning. Eric Sandeen mentioned this commit
> > in the other part of the thread, and made an update with that patch
> > which is now in updates-testing.
> > 
> > https://bugzilla.redhat.com/show_bug.cgi?id=1201979 is about systemd
> > being stupid and rerunning root fsck, which sometimes triggered the
> > first issue. I just posted a patch upstream:
> > http://lists.freedesktop.org/archives/systemd-devel/2015-May/031445.html
> 
> Well, note that this one is triggered if the system boots up with
> read-only root, which is not how Fedora sets things up by default...
Yeah. There are legitimate setups with ro root, but they certainly are a monority.
Incidentally, since ro-at-boot is used mostly on old installations, a large
number have big slow drives, which exacerbates the problem.

For majority of ro-at-boot setups, changing to rw would be the best and the simplest
solution. I don't think we should do that automatically (e.g. through rpm macro),
but instead encourage people to switch manually. I have no idea what would
be a good place to put this information though.

Zbyszek