linux-kernel - Re: [PATCH 2/2] xen/manage: Poweroff forcefully if user-space is not yet up.

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Message-ID: <5342DE24.8080804@citrix.com>
Date:	Mon, 7 Apr 2014 18:19:32 +0100
From:	David Vrabel <david.vrabel@...rix.com>
To:	Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>
CC:	<boris.ostrovsky@...cle.com>, <xen-devel@...ts.xenproject.org>,
	<linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 2/2] xen/manage: Poweroff forcefully if user-space is
 not yet up.

On 04/04/14 19:53, Konrad Rzeszutek Wilk wrote:
> The user can launch the guest in this sequence:
> 
> xl create -p /vm.cfg	[launch, but pause it]
> xl shutdown latest	[sets control/shutdown=poweroff]
> xl unpause latest
> xl console latest	[and see that the guest has completely
> ignored the shutdown request]
> 
> In reality the guest hasn't ignored it. It registers a watch
> and gets a notification that there is value. It then calls
> the shutdown_handler which ends up calling orderly_shutdown.
> 
> Unfortunately that is so early in the bootup that there
> are no user-space. Which means that the orderly_shutdown fails.
> But since the force flag was set to false it continues on without
> reporting.
> 
> What we really want to is to use the force when we are in the
> SYSTEM_BOOTING state and not use the 'force' when SYSTEM_RUNNING.
> 
> However, if we are in the running state - and the shutdown command
> has been given before the user-space has been setup, there is nothing
> we can do. Worst yet, we stop ignoring the 'xl shutdown' requests!
> 
> As such, the other part of this patch is to only stop ignoring
> the 'xl shutdown' when we are truly in the power off sequence.
> 
> That means the user can do multiple 'xl shutdown' and we will try
> to act on them instead of ignoring them.

Applied to devel/for-linus-3.15

> Fixes-Bug: http://bugs.xenproject.org/xen/bug/6
> Reported-by:  Alex Bligh <alex@...x.org.uk>
> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>
> [v2: Add switch statement]
> [v3: Add a reboot notifier]

Can you put this version information after the --- in future?

Thanks.

David
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