First thought: Even without the exit code or anything, it's going to be -EBUSY like 99.999% of the time. Not much else can fail during umount.<div><br></div><div>And ”Filesystem is busy" would perfectly fit the earlier error message which you overlooked:</div><div><br></div><div>"Process 304 (plymouthd) has been marked to be excluded from killing.<br>It is running from the root file system, and thus likely to block<br>re-mounting of the root file system to read-only."</div><div><br></div><div>So you have a process holding / open (Plymouth is the boot splash screen app) and the kernel doesn't allow it to be umounted due to that.<br><br><div class="gmail_quote"><div dir="ltr">On Tue, Mar 21, 2017, 05:25 Chris Murphy <<a href="mailto:lists@colorremedies.com">lists@colorremedies.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Any thoughts on this?<br class="gmail_msg">
<br class="gmail_msg">
I've followed these instructions:<br class="gmail_msg">
<a href="https://freedesktop.org/wiki/Software/systemd/Debugging/" rel="noreferrer" class="gmail_msg" target="_blank">https://freedesktop.org/wiki/Software/systemd/Debugging/</a><br class="gmail_msg">
Shutdown Completes Eventually<br class="gmail_msg">
<br class="gmail_msg">
However, no additional information is being logged that gives any<br class="gmail_msg">
answer to why there are three remount ro attempts, and why they aren't<br class="gmail_msg">
succeeding.<br class="gmail_msg">
<br class="gmail_msg">
<a href="https://github.com/systemd/systemd/blob/master/src/core/umount.c" rel="noreferrer" class="gmail_msg" target="_blank">https://github.com/systemd/systemd/blob/master/src/core/umount.c</a><br class="gmail_msg">
line 409<br class="gmail_msg">
<br class="gmail_msg">
This suggests three ro attempts shouldn't happen. And then 413 says<br class="gmail_msg">
that / won't actually get umounted, reboot happens leaving it ro<br class="gmail_msg">
mounted. So the "All filesystems unmounted." doesn't tell us anything;<br class="gmail_msg">
but it does seem like there should be a way to expose exit code for<br class="gmail_msg">
umount. I'm just not sure how to do it, and if that means compiling<br class="gmail_msg">
systemd myself.<br class="gmail_msg">
<br class="gmail_msg">
--<br class="gmail_msg">
Chris Murphy<br class="gmail_msg">
_______________________________________________<br class="gmail_msg">
systemd-devel mailing list<br class="gmail_msg">
<a href="mailto:systemd-devel@lists.freedesktop.org" class="gmail_msg" target="_blank">systemd-devel@lists.freedesktop.org</a><br class="gmail_msg">
<a href="https://lists.freedesktop.org/mailman/listinfo/systemd-devel" rel="noreferrer" class="gmail_msg" target="_blank">https://lists.freedesktop.org/mailman/listinfo/systemd-devel</a><br class="gmail_msg">
</blockquote></div></div><div dir="ltr">-- <br></div><div data-smartmail="gmail_signature"><p dir="ltr">Mantas Mikulėnas <<a href="mailto:grawity@gmail.com">grawity@gmail.com</a>><br>
Sent from my phone</p>
</div>