[PATCH v2 09/12] x86/vmce, tools/libxl: expose LMCE capability in guest MSR_IA32_MCG_CAP

[Haozhong Zhang <haozhong.zhang@intel.com>]

If LMCE is supported by host and ' mca_caps = [ "lmce" ] ' is present
in xl config, the LMCE capability will be exposed in guest MSR_IA32_MCG_CAP.
By default, LMCE is not exposed to guest so as to keep the backwards migration
compatibility.

Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
---
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>

Changes in v2:
 * Allow restore an LMCE enabled guest on an LMCE-incapable host.
 * Change xl config to "mca_caps = [ "lmce" ]", which can be extended to
   support other MCA capabilities in the future.
---
 docs/man/xl.cfg.pod.5.in        | 24 ++++++++++++++++++++++++
 tools/libxl/libxl_dom.c         | 30 ++++++++++++++++++++++++++++++
 tools/libxl/libxl_types.idl     |  1 +
 tools/xl/xl_parse.c             |  4 ++++
 xen/arch/x86/cpu/mcheck/vmce.c  | 19 ++++++++++++++++++-
 xen/arch/x86/hvm/hvm.c          |  5 +++++
 xen/include/asm-x86/mce.h       |  1 +
 xen/include/public/hvm/params.h |  7 ++++++-
 8 files changed, 89 insertions(+), 2 deletions(-)

diff --git a/docs/man/xl.cfg.pod.5.in b/docs/man/xl.cfg.pod.5.in
index 505c111..d75dcd2 100644
--- a/docs/man/xl.cfg.pod.5.in
+++ b/docs/man/xl.cfg.pod.5.in
@@ -2021,6 +2021,30 @@ natively or via hardware backwards compatibility support.
 
 =back
 
+=head3 x86
+
+=over 4
+
+=item B<mca_caps=[ "CAP", "CAP", ... ]>
+
+(HVM only) Enable MCA capabilities besides default ones enabled
+by Xen hypervisor for the HVM domain. "CAP" can be one in the
+following list:
+
+=over 4
+
+=item B<"lmce">
+
+Intel local MCE
+
+=item B<default>
+
+No MCA capabilities in above list are enabled.
+
+=back
+
+=back
+
 =head1 SEE ALSO
 
 =over 4
diff --git a/tools/libxl/libxl_dom.c b/tools/libxl/libxl_dom.c
index d519c8d..91b2f08 100644
--- a/tools/libxl/libxl_dom.c
+++ b/tools/libxl/libxl_dom.c
@@ -275,6 +275,32 @@ err:
     libxl_bitmap_dispose(&enlightenments);
     return ERROR_FAIL;
 }
+
+static int hvm_set_mca_capabilities(libxl__gc *gc, uint32_t domid,
+                                    libxl_domain_build_info *const info)
+{
+    int i, rc = 0;
+    const libxl_string_list xl_caps = info->u.hvm.mca_caps;
+    unsigned long caps = 0;
+
+    if (!xl_caps)
+        return 0;
+
+    for (i = 0; xl_caps[i] != NULL; i++) {
+        if (!strcmp(xl_caps[i], "lmce"))
+            caps |= HVMMCA_CAP_LMCE;
+        else {
+            LOG(ERROR, "Unsupported MCA capability %s", xl_caps[i]);
+            rc = ERROR_FAIL;
+            break;
+        }
+    }
+
+    if (!rc)
+        rc = xc_hvm_param_set(CTX->xch, domid, HVM_PARAM_MCA_CAP, caps);
+
+    return rc;
+}
 #endif
 
 static void hvm_set_conf_params(xc_interface *handle, uint32_t domid,
@@ -438,6 +464,10 @@ int libxl__build_pre(libxl__gc *gc, uint32_t domid,
         rc = hvm_set_viridian_features(gc, domid, info);
         if (rc)
             return rc;
+
+        rc = hvm_set_mca_capabilities(gc, domid, info);
+        if (rc)
+            return rc;
 #endif
     }
 
diff --git a/tools/libxl/libxl_types.idl b/tools/libxl/libxl_types.idl
index a612d1f..71c6c33 100644
--- a/tools/libxl/libxl_types.idl
+++ b/tools/libxl/libxl_types.idl
@@ -550,6 +550,7 @@ libxl_domain_build_info = Struct("domain_build_info",[
                                        ("serial_list",      libxl_string_list),
                                        ("rdm", libxl_rdm_reserve),
                                        ("rdm_mem_boundary_memkb", MemKB),
+                                       ("mca_caps",         libxl_string_list),
                                        ])),
                  ("pv", Struct(None, [("kernel", string),
                                       ("slack_memkb", MemKB),
diff --git a/tools/xl/xl_parse.c b/tools/xl/xl_parse.c
index 1ef0c27..11a9f51 100644
--- a/tools/xl/xl_parse.c
+++ b/tools/xl/xl_parse.c
@@ -1084,6 +1084,10 @@ void parse_config_data(const char *config_source,
 
         if (!xlu_cfg_get_long (config, "rdm_mem_boundary", &l, 0))
             b_info->u.hvm.rdm_mem_boundary_memkb = l * 1024;
+
+        xlu_cfg_get_list_as_string_list(config, "mca_caps",
+                                        &b_info->u.hvm.mca_caps, false);
+
         break;
     case LIBXL_DOMAIN_TYPE_PV:
     {
diff --git a/xen/arch/x86/cpu/mcheck/vmce.c b/xen/arch/x86/cpu/mcheck/vmce.c
index 994a50e..5dc790f 100644
--- a/xen/arch/x86/cpu/mcheck/vmce.c
+++ b/xen/arch/x86/cpu/mcheck/vmce.c
@@ -74,7 +74,7 @@ int vmce_restore_vcpu(struct vcpu *v, const struct hvm_vmce_vcpu *ctxt)
     unsigned long guest_mcg_cap;
 
     if ( boot_cpu_data.x86_vendor == X86_VENDOR_INTEL )
-        guest_mcg_cap = INTEL_GUEST_MCG_CAP;
+        guest_mcg_cap = INTEL_GUEST_MCG_CAP | MCG_LMCE_P;
     else
         guest_mcg_cap = AMD_GUEST_MCG_CAP;
 
@@ -546,3 +546,20 @@ int unmmap_broken_page(struct domain *d, mfn_t mfn, unsigned long gfn)
     return rc;
 }
 
+int vmce_enable_mca_cap(struct domain *d, uint64_t cap)
+{
+    struct vcpu *v;
+
+    if ( cap & ~HVMMCA_CAP_MASK )
+        return -EINVAL;
+
+    if ( cap & HVMMCA_CAP_LMCE )
+    {
+        if ( !lmce_support )
+            return -EINVAL;
+        for_each_vcpu(d, v)
+            v->arch.vmce.mcg_cap |= MCG_LMCE_P;
+    }
+
+    return 0;
+}
diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c
index ccfae4f..0007e3d 100644
--- a/xen/arch/x86/hvm/hvm.c
+++ b/xen/arch/x86/hvm/hvm.c
@@ -4045,6 +4045,7 @@ static int hvm_allow_set_param(struct domain *d,
     case HVM_PARAM_IOREQ_SERVER_PFN:
     case HVM_PARAM_NR_IOREQ_SERVER_PAGES:
     case HVM_PARAM_ALTP2M:
+    case HVM_PARAM_MCA_CAP:
         if ( value != 0 && a->value != value )
             rc = -EEXIST;
         break;
@@ -4257,6 +4258,10 @@ static int hvmop_set_param(
                                                (0x10000 / 8) + 1) << 32);
         a.value |= VM86_TSS_UPDATED;
         break;
+
+    case HVM_PARAM_MCA_CAP:
+        rc = vmce_enable_mca_cap(d, a.value);
+        break;
     }
 
     if ( rc != 0 )
diff --git a/xen/include/asm-x86/mce.h b/xen/include/asm-x86/mce.h
index dee66b3..70eb50c 100644
--- a/xen/include/asm-x86/mce.h
+++ b/xen/include/asm-x86/mce.h
@@ -38,6 +38,7 @@ extern int vmce_restore_vcpu(struct vcpu *, const struct hvm_vmce_vcpu *);
 extern int vmce_wrmsr(uint32_t msr, uint64_t val);
 extern int vmce_rdmsr(uint32_t msr, uint64_t *val);
 extern bool vmce_support_lmce(const struct vcpu *v);
+extern int vmce_enable_mca_cap(struct domain *d, uint64_t cap);
 
 extern unsigned int nr_mce_banks;
 
diff --git a/xen/include/public/hvm/params.h b/xen/include/public/hvm/params.h
index 58c8478..266c123 100644
--- a/xen/include/public/hvm/params.h
+++ b/xen/include/public/hvm/params.h
@@ -259,6 +259,11 @@
  */
 #define HVM_PARAM_VM86_TSS_SIZED 37
 
-#define HVM_NR_PARAMS 38
+/* Enable MCA capabilities. */
+#define HVM_PARAM_MCA_CAP 38
+#define HVMMCA_CAP_LMCE   (1UL << 27)
+#define HVMMCA_CAP_MASK   HVMMCA_CAP_LMCE
+
+#define HVM_NR_PARAMS 39
 
 #endif /* __XEN_PUBLIC_HVM_PARAMS_H__ */
-- 
2.10.1


_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel