linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: David Vrabel <david.vrabel@citrix.com>
To: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: <Ian.Campbell@citrix.com>, <xen-devel@lists.xenproject.org>,
	<linux-kernel@vger.kernel.org>, <JBeulich@suse.com>,
	<boris.ostrovsky@oracle.com>
Subject: Re: [PATCH 3/4] xen/manage: Guard against user-space initiated poweroff and XenBus.
Date: Thu, 21 Nov 2013 11:09:52 +0000	[thread overview]
Message-ID: <528DEA00.7070505@citrix.com> (raw)
In-Reply-To: <1383932286-25080-4-git-send-email-konrad.wilk@oracle.com>

On 08/11/13 17:38, Konrad Rzeszutek Wilk wrote:
> There is a race case where the user does 'poweroff'
> and at the same time the system admin does 'xl shutdown'.

This isn't a Xen-specific problem is it?  Wouldn't it be better to fix
this in generic code?

Especially since I don't think this patch actually fixes the race
completely.

> --- a/drivers/xen/manage.c
> +++ b/drivers/xen/manage.c
[...]
> @@ -222,7 +230,7 @@ static void shutdown_handler(struct xenbus_watch *watch,
>  	};
>  	static struct shutdown_handler *handler;
>  
> -	if (shutting_down != SHUTDOWN_INVALID)
> +	if (atomic_read(&shutting_down) != SHUTDOWN_INVALID)
>  		return;

In guest initiated poweroff at this time will still race with this
toolstack initiated poweroff.

David

  parent reply	other threads:[~2013-11-21 11:09 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-11-08 17:38 [PATCH] Fixes to Linux v3.13 - bugs.xenproject.org ones. (v1) Konrad Rzeszutek Wilk
2013-11-08 17:38 ` [PATCH 1/4] xen/mcfg: Call PHYSDEVOP_pci_mmcfg_reserved for MCFG areas Konrad Rzeszutek Wilk
2013-11-21 10:37   ` David Vrabel
2013-11-08 17:38 ` [PATCH 2/4] xen/manage: Poweroff forcefully if user-space is not yet up Konrad Rzeszutek Wilk
2013-11-20 21:11   ` Boris Ostrovsky
2013-11-21 11:33   ` David Vrabel
2013-11-26 16:47     ` Konrad Rzeszutek Wilk
2014-04-01 15:43     ` Konrad Rzeszutek Wilk
2013-11-08 17:38 ` [PATCH 3/4] xen/manage: Guard against user-space initiated poweroff and XenBus Konrad Rzeszutek Wilk
2013-11-20 21:40   ` Boris Ostrovsky
2013-11-21 11:09   ` David Vrabel [this message]
2013-11-26 16:45     ` Konrad Rzeszutek Wilk
2013-12-02 11:27       ` David Vrabel
2014-03-31 19:09         ` Konrad Rzeszutek Wilk
2014-04-01 13:18   ` David Vrabel
2014-04-01 14:03     ` Konrad Rzeszutek Wilk
2013-11-08 17:38 ` [PATCH 4/4] xen/xenbus: Avoid synchronous wait on XenBus stalling shutdown/restart Konrad Rzeszutek Wilk
2013-11-21 17:52   ` [Xen-devel] " David Vrabel
2013-11-22  9:30     ` Ian Campbell
2013-11-26 16:50     ` Konrad Rzeszutek Wilk
2013-12-02 11:41       ` David Vrabel
2014-03-31 20:33         ` Konrad Rzeszutek Wilk
2014-04-01 12:53           ` David Vrabel
2014-01-26  1:13   ` Zhang, Yang Z
2014-01-26  3:44     ` Konrad Rzeszutek Wilk
2014-04-03 11:59 ` [PATCH] Fixes to Linux v3.13 - bugs.xenproject.org ones. (v1) David Vrabel
2014-04-03 18:07   ` Konrad Rzeszutek Wilk

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=528DEA00.7070505@citrix.com \
    --to=david.vrabel@citrix.com \
    --cc=Ian.Campbell@citrix.com \
    --cc=JBeulich@suse.com \
    --cc=boris.ostrovsky@oracle.com \
    --cc=konrad.wilk@oracle.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=xen-devel@lists.xenproject.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).