1020-xen-tell-guests-what-speculative-workarounds-are-not.patch

From 6a3be9a4d752ecc5af6fb61dbfc8f53a948c2556 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marek=20Marczykowski-G=C3=B3recki?=
 <marmarek@invisiblethingslab.com>
Date: Thu, 2 Feb 2023 20:42:27 +0100
Subject: [PATCH] xen: tell guests what speculative workarounds are not
 necessary
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Expose arch caps to guests, so the guest kernel can do a better choice
what workarounds are necessary on a given platform. This is
fundamentally incompatible with migration, but since we don't do
migration, we can recover some performance.

Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
---
 xen/arch/x86/msr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/xen/arch/x86/msr.c b/xen/arch/x86/msr.c
index 317b154d244d..140a3c297be0 100644
--- a/xen/arch/x86/msr.c
+++ b/xen/arch/x86/msr.c
@@ -157,7 +157,7 @@ int init_domain_msr_policy(struct domain *d)
      * so dom0 can turn off workarounds as appropriate.  Temporary, until the
      * domain policy logic gains a better understanding of MSRs.
      */
-    if ( is_hardware_domain(d) && cpu_has_arch_caps )
+    if ( cpu_has_arch_caps )
     {
         uint64_t val;
 
-- 
2.37.3