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Message-ID: <573ce7fa-d64f-7351-b64d-01692fc87512@oracle.com>
Date:   Mon, 3 Jul 2023 13:51:57 -0400
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Subject: Re: [PATCH] x86/xen: fix secondary processor fpu initialization
Content-Language: en-US
To:     Juergen Gross <jgross@suse.com>, linux-kernel@vger.kernel.org,
        x86@kernel.org
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        "H. Peter Anvin" <hpa@zytor.com>, xen-devel@lists.xenproject.org
References: <20230703130032.22916-1-jgross@suse.com>
From:   Boris Ostrovsky <boris.ostrovsky@oracle.com>
In-Reply-To: <20230703130032.22916-1-jgross@suse.com>
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On 7/3/23 9:00 AM, Juergen Gross wrote:
> Moving the call of fpu__init_cpu() from cpu_init() to start_secondary()
> broke Xen PV guests, as those don't call start_secondary() for APs.
> 
> Fix that by adding the call of fpu__init_cpu() to cpu_bringup(), which
> is the Xen PV replacement of start_secondary().
> 
> Fixes: b81fac906a8f ("x86/fpu: Move FPU initialization into arch_cpu_finalize_init()")
> Signed-off-by: Juergen Gross <jgross@suse.com>


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