[xen master] x86: don't allow Dom0 (direct) access to port F0

[patchbot@xxxxxxx]

commit 86266162fc09d1472dc1f70ce329386cb4b2cc91
Author:     Jan Beulich <jbeulich@xxxxxxxx>
AuthorDate: Thu Nov 2 10:45:39 2023 +0100
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Thu Nov 2 10:45:39 2023 +0100

    x86: don't allow Dom0 (direct) access to port F0
    
    This controls the driving of IGNNE# (if such emulation is enabled in
    hardware), and hence would need proper handling in the hypervisor to be
    safe to use by Dom0 (and fully emulating for PVH/HVM DomU-s).
    
    Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
    Acked-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
---
 xen/arch/x86/dom0_build.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/xen/arch/x86/dom0_build.c b/xen/arch/x86/dom0_build.c
index 640e666685..e734622400 100644
--- a/xen/arch/x86/dom0_build.c
+++ b/xen/arch/x86/dom0_build.c
@@ -492,6 +492,9 @@ int __init dom0_setup_permissions(struct domain *d)
     /* INIT# and alternative A20M# control. */
     rc |= ioports_deny_access(d, 0x92, 0x92);
 
+    /* IGNNE# control. */
+    rc |= ioports_deny_access(d, 0xF0, 0xF0);
+
     /* ACPI PM Timer. */
     if ( pmtmr_ioport )
         rc |= ioports_deny_access(d, pmtmr_ioport, pmtmr_ioport + 3);
--
generated by git-patchbot for /home/xen/git/xen.git#master