From mboxrd@z Thu Jan  1 00:00:00 1970
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From: Richard Weinberger <richard@nod.at>
Subject: Re: [uml-devel] UML hangs with hrtimer test module
Date: Wed, 28 Mar 2018 15:19:07 +0200
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To: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Joel Fernandes <agnel.joel@gmail.com>, uml-devel <user-mode-linux-devel@lists.sourceforge.net>, Jeff Dike <jdike@addtoit.com>
List-ID: <user-mode-linux-devel.lists.sourceforge.net>

Am Mittwoch, 28. M=E4rz 2018, 15:11:29 CEST schrieb Geert Uytterhoeven:
> On Wed, Mar 28, 2018 at 12:28 PM, Joel Fernandes <agnel.joel@gmail.com>=20
wrote:
> >         while(release_now =3D=3D 0);
>=20
> while (release_now =3D=3D 0)
>         cpu_relax();

Not sure whether a cpu_relax() fixes the problem.
I guess the root of the problem is that UML is UP and non-preemptive.=20
Therefore the loop is never interrupted.
To verify I asked for the full source.

Thanks,
//richard