From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dario Faggioli <dario.faggioli@citrix.com>
Subject: Re: [Help] Trigger Watchdog when adding an IPI in
 vcpu_wake
Date: Thu, 22 Sep 2016 11:55:16 +0200
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References: <20160913085437.GA14514@linux-gk3p>
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On Thu, 2016-09-22 at 11:12 +0200, Dario Faggioli wrote:
> _Almost_ correct. However, the problem is more that vcpu_wake() can
> happen in response to an IRQ, and when you grab a spinlock in IRQ
> context, you need to disable IRQs.
>=20
> There is a good explanation of why, here:
>=20
Ah, sorry, link is missing! Here:

https://www.kernel.org/doc/Documentation/locking/spinlocks.txt

Read the "Lesson 3: spinlocks revisited." section.

Dario
--=20
<<This happens because I choose it to happen!>> (Raistlin Majere)
-----------------------------------------------------------------
Dario Faggioli, Ph.D, http://about.me/dario.faggioli
Senior Software Engineer, Citrix Systems R&D Ltd., Cambridge (UK)
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