x86: vMCE emulation

This patch provides virtual MCE support to guest. It emulates a simple
and clean MCE MSRs interface to guest by faking caps to guest if needed
and masking caps if unnecessary:
1. Providing a well-defined MCG_CAP to guest, filter out un-necessary
   caps and provide only guest needed caps;
2. Disabling MCG_CTL to avoid model specific;
3. Sticking all 1's to MCi_CTL to guest to avoid model specific;
4. Enabling CMCI cap but never really inject to guest to prevent
   polling periodically;
5. Masking MSCOD field of MCi_STATUS to avoid model specific;
6. Keeping natural semantics by per-vcpu instead of per-domain
   variables;
7. Using bank1 and reserving bank0 to work around 'bank0 quirk' of some
   very old processors;
8. Cleaning some vMCE# injection logic which shared by Intel and AMD
   but useless under new vMCE implement;
9. Keeping compatilbe w/ old xen version which has been backported to
   SLES11 SP2, so that old vMCE would not blocked when migrate to new
   vMCE;

Signed-off-by: Liu, Jinsong <jinsong.liu@intel.com>

- make printing consistent (and non-exploitable)
- fix return values of intel_mce_{rd,wr}msr() for out of range banks
- miscellaneous cleanup

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Committed-by: Jan Beulich <jbeulich@suse.com>

1 files changed, 2 insertions, 5 deletions

diff --git a/xen/include/asm-x86/domain.h b/xen/include/asm-x86/domain.h
index 973a774f1b..1b2a770dae 100644
--- a/xen/include/asm-x86/domain.h
+++ b/xen/include/asm-x86/domain.h
@@ -296,9 +296,6 @@ struct arch_domain
 
     struct PITState vpit;
 
-    /* For Guest vMCA handling */
-    struct domain_mca_msrs *vmca_msrs;
-
     /* TSC management (emulation, pv, scaling, stats) */
     int tsc_mode;            /* see include/asm-x86/time.h */
     bool_t vtsc;             /* tsc is emulated (may change after migrate) */
@@ -438,8 +435,8 @@ struct arch_vcpu
      * and thus should be saved/restored. */
     bool_t nonlazy_xstate_used;
 
-    uint64_t mcg_cap;
-    
+    struct vmce vmce;
+
     struct paging_vcpu paging;
 
     uint32_t gdbsx_vcpu_event;