x86 mce: Fix panic in mcheck_mca_logout

I met the following panic message in mcheck_mca_logout().
MSR_IA32_MCi_ADDR might take the values other than the machine
address. FATAL PAGE FAULT occured when the non-existent address is
passed to maddr_get_owner().

Signed-off-by: Kazuhiro Suzuki <kaz@jp.fujitsu.com>

diff --git a/xen/arch/x86/cpu/mcheck/mce.c b/xen/arch/x86/cpu/mcheck/mce.c
index e20898ed52bf9e4d56dfdcbc058f79f28f7d0954..8866e130bbd29b752ecb1066d4ec1328db50082d 100644 (file)
--- a/xen/arch/x86/cpu/mcheck/mce.c
+++ b/xen/arch/x86/cpu/mcheck/mce.c
@@ -237,10 +237,12 @@ mctelem_cookie_t mcheck_mca_logout(enum mca_source who, cpu_banks_t bankmask,
 
                if (status & MCi_STATUS_ADDRV) {
                        mca_rdmsrl(MSR_IA32_MC0_ADDR + 4 * i, addr);
-                       d = maddr_get_owner(addr);
-                       if (d != NULL && (who == MCA_POLLER ||
-                           who == MCA_CMCI_HANDLER))
-                               mcb.mc_domid = d->domain_id;
+                       if (mfn_valid(paddr_to_pfn(addr))) {
+                               d = maddr_get_owner(addr);
+                               if (d != NULL && (who == MCA_POLLER ||
+                                   who == MCA_CMCI_HANDLER))
+                                       mcb.mc_domid = d->domain_id;
+                       }
                }
 
                if (status & MCi_STATUS_MISCV)