On 2/14/23 6:53 PM, Boris Ostrovsky wrote:
On 2/14/23 11:13 AM, Jan Beulich wrote:
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -18,6 +18,8 @@
#include <linux/pgtable.h>
#include <linux/bpf.h>
+#include <xen/xen.h>
+
#include <asm/spec-ctrl.h>
#include <asm/cmdline.h>
#include <asm/bugs.h>
@@ -32,6 +34,7 @@
#include <asm/intel-family.h>
#include <asm/e820/api.h>
#include <asm/hypervisor.h>
+#include <asm/xen/hypervisor.h>
#include <asm/tlbflush.h>
#include "cpu.h"
@@ -934,7 +937,8 @@ do_cmd_auto:
break;
case RETBLEED_MITIGATION_IBPB:
- setup_force_cpu_cap(X86_FEATURE_ENTRY_IBPB);
+ if (!xen_pv_domain() || xen_vm_assist_ibpb(true))
Is this going to compile without CONFIG_XEN?
I also think these two conditions should be wrapped into something to limit
exposure of non-Xen code to Xen-specific primitives.
Oh, and this needs x86 maintainers.
-boris
