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Message-ID: <762802a4b8ff21e43e59e222e472ab9b23fc43cd.camel@infradead.org>
Subject: Re: [PATCH 0/2] xen: fix two issues in Xen pv qspinlock handling
From:   David Woodhouse <dwmw2@infradead.org>
To:     Juergen Gross <jgross@suse.com>, linux-kernel@vger.kernel.org,
        xen-devel@lists.xenproject.org, x86@kernel.org
Cc:     boris.ostrovsky@oracle.com, hpa@zytor.com, tglx@linutronix.de,
        mingo@redhat.com, bp@alien8.de, Waiman.Long@hp.com,
        peterz@infradead.org
Date:   Tue, 09 Oct 2018 15:40:16 +0100
In-Reply-To: <20181001071641.19282-1-jgross@suse.com>
References: <20181001071641.19282-1-jgross@suse.com>
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On Mon, 2018-10-01 at 09:16 +0200, Juergen Gross wrote:
> The Xen specific queue spinlock wait function has two issues which
> could result in a hanging system.
>=20
> They have a similar root cause of clearing a pending wakeup of a
> waiting vcpu and later going to sleep waiting for the just cleared
> wakeup event, which of course won't ever happen.
>=20
> Juergen Gross (2):
>   xen: fix race in xen_qlock_wait()
>   xen: make xen_qlock_wait() nestable
>=20
>  arch/x86/xen/spinlock.c | 33 ++++++++++++---------------------
>  1 file changed, 12 insertions(+), 21 deletions(-)
>=20
> Cc: Waiman.Long@hp.com
> Cc: peterz@infradead.org

LGTM. Both these should be Cc:stable@vger.kernel.org, yes?

Thanks.

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