From 3f8968f1f0ad259591a0f050372c4abe3aa9b067 Mon Sep 17 00:00:00 2001
From: Juergen Gross <jgross@suse.com>
Date: Mon, 3 Jul 2023 15:00:32 +0200
Subject: [PATCH] x86/xen: Fix secondary processors' FPU initialization
commit fe3e0a13e597c1c8617814bf9b42ab732db5c26e upstream.
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.
Call fpu__init_cpu() in Xen's 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>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230703130032.22916-1-jgross@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/x86/xen/smp_pv.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/arch/x86/xen/smp_pv.c b/arch/x86/xen/smp_pv.c
index 928fbe63c96f..3a0a27d94c05 100644
--- a/arch/x86/xen/smp_pv.c
+++ b/arch/x86/xen/smp_pv.c
@@ -28,6 +28,7 @@
#include <asm/desc.h>
#include <asm/pgtable.h>
#include <asm/cpu.h>
+#include <asm/fpu/internal.h>
#include <xen/interface/xen.h>
#include <xen/interface/vcpu.h>
@@ -61,6 +62,7 @@ static void cpu_bringup(void)
cr4_init();
cpu_init();
+ fpu__init_cpu();
touch_softlockup_watchdog();
preempt_disable();