Re: Long delays and keystrokes required - related to disk encryption?

From: Arjan van de Ven
Date: Tue Oct 28 2008 - 23:32:56 EST


Frans Pop wrote:
On Tuesday 28 October 2008, Frans Pop wrote:
I'm seeing some very strange behavior with 2.6.28-rc2-95-g49fdf67 on my
HP 2510p notebook.

During the boot there are several places where I need to hit a key for
the boot to continue. There are also some very long delays before the
next syslog message is displayed.
The boot does continue and regularly hitting a key helps (but does not
get rid of all delays), but it is a huge regression from 2.6.27.

The delays seem to continue until file systems get mounted.

As the delays start at the point my system asks for the passphrase to
unlock (LUKS) encrypted disks, I suspect it has to do with that.
Especially since hitting a key seems to "trigger" new disk activity.

However, the delays happen _again_ during shutdown, which makes it
extra strange that the system does behave normally when logged in.

During the first boot wireless networking failed. During the second
boot, wireless networking did come up (without any relevant changes).
This gave an interesting extra data point: with wireless the delays on
shutdown started later: after iwlagn gets disabled.

I've bisected it to:
commit dc4304f7deee29fcdf6a2b62f7146ea7f505fd42
Author: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
Date: Mon Oct 13 10:32:15 2008 -0400
rangetimers: fix the bug reported by Ingo for real

The bisection was one of those annoying ones where you switch branches
often and get a load of config changes. This means that I'm not 100% sure
about it, especially as the behavior changed for the last few "bad"s:
instead of endlessly repeated delays there would be only a few of them
immediately after entering the LUKS passphrase.

ok one easy thing to try, in the peek function (that this patch touches),
just stick a "return" as first statement in.
If that "fixes" it, we have a real issue with hrtimers, if not then something else is going on..

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