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Subject: Re: [PATCH] xen: remove stray preempt_disable() from PV AP startup
 code
To:     Juergen Gross <jgross@suse.com>, xen-devel@lists.xenproject.org,
        x86@kernel.org, linux-kernel@vger.kernel.org
Cc:     Stefano Stabellini <sstabellini@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        "H. Peter Anvin" <hpa@zytor.com>
References: <20210825113158.11716-1-jgross@suse.com>
From:   Boris Ostrovsky <boris.ostrovsky@oracle.com>
Message-ID: <df9f93ae-a833-8bf0-9df6-91cf2c4e007b@oracle.com>
Date:   Wed, 8 Sep 2021 10:21:20 -0400
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On 8/25/21 7:31 AM, Juergen Gross wrote:
> In cpu_bringup() there is a call of preempt_disable() without a paired
> preempt_enable(). This is not needed as interrupts are off initially.
> Additionally this will result in early boot messages like:
>
> BUG: scheduling while atomic: swapper/1/0/0x00000002
>
> Signed-off-by: Juergen Gross <jgross@suse.com>


Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>