pr_warning("Corrupted IC MCE info?\n");
 }
 
+static void amd_decode_bu_mce(u64 mc2_status)
+{
+       u32 ec = mc2_status & 0xffff;
+       u32 xec = (mc2_status >> 16) & 0xf;
+
+       pr_emerg(" Bus Unit Error");
+
+       if (xec == 0x1)
+               pr_cont(" in the write data buffers.\n");
+       else if (xec == 0x3)
+               pr_cont(" in the victim data buffers.\n");
+       else if (xec == 0x2 && MEM_ERROR(ec))
+               pr_cont(": %s error in the L2 cache tags.\n", RRRR_MSG(ec));
+       else if (xec == 0x0) {
+               if (TLB_ERROR(ec))
+                       pr_cont(": %s error in a Page Descriptor Cache or "
+                               "Guest TLB.\n", TT_MSG(ec));
+               else if (BUS_ERROR(ec))
+                       pr_cont(": %s/ECC error in data read from NB: %s.\n",
+                               RRRR_MSG(ec), PP_MSG(ec));
+               else if (MEM_ERROR(ec)) {
+                       u8 rrrr = (ec >> 4) & 0xf;
+
+                       if (rrrr >= 0x7)
+                               pr_cont(": %s error during data copyback.\n",
+                                       RRRR_MSG(ec));
+                       else if (rrrr <= 0x1)
+                               pr_cont(": %s parity/ECC error during data "
+                                       "access from L2.\n", RRRR_MSG(ec));
+                       else
+                               goto wrong_bu_mce;
+               } else
+                       goto wrong_bu_mce;
+       } else
+               goto wrong_bu_mce;
+
+       return;
+
+wrong_bu_mce:
+       pr_warning("Corrupted BU MCE info?\n");
+}
+
 void amd_decode_nb_mce(int node_id, struct err_regs *regs, int handle_errors)
 {
        u32 ec  = ERROR_CODE(regs->nbsl);
                amd_decode_ic_mce(m->status);
                break;
 
+       case 2:
+               amd_decode_bu_mce(m->status);
+               break;
+
        case 4:
                regs.nbsl  = (u32) m->status;
                regs.nbsh  = (u32)(m->status >> 32);