From 30d65d1b19850c9bc8c17dba8ebe9be5e0c17054 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Thu, 15 Jun 2023 14:39:59 +0200 Subject: [PATCH] x86/xen: Set default memory type for PV guests to WB When running as an unprivileged PV guest under Xen (not dom0), the default MTRR memory type should be write-back. Signed-off-by: Juergen Gross Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Boris Ostrovsky Link: https://lore.kernel.org/r/20230615123959.12298-1-jgross@suse.com --- arch/x86/xen/enlighten_pv.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c index 8732b85d56505..93b658248d013 100644 --- a/arch/x86/xen/enlighten_pv.c +++ b/arch/x86/xen/enlighten_pv.c @@ -187,6 +187,8 @@ static void __init xen_pv_init_platform(void) if (xen_initial_domain()) xen_set_mtrr_data(); + else + mtrr_overwrite_state(NULL, 0, MTRR_TYPE_WRBACK); } static void __init xen_pv_guest_late_init(void) -- 2.30.2