diff --git a/arch/alpha/kernel/err_common.c b/arch/alpha/kernel/err_common.c
index 94e1b3dcf6d4..9271ea425a7b 100644
--- a/arch/alpha/kernel/err_common.c
+++ b/arch/alpha/kernel/err_common.c
@@ -44,6 +44,19 @@ mchk_dump_mem(void *data, size_t length, char **annotation)
 	}
 }
 
+/* Preserve rejected frames without trusting their internal offsets. */
+void
+mchk_dump_logout_frame_raw(struct el_common *header)
+{
+	size_t length = header->size;
+
+	/* Bound diagnostic output and never read a partial final quadword. */
+	if (length > 1024)
+		length = 1024;
+	length &= ~7UL;
+	mchk_dump_mem(header, length, NULL);
+}
+
 void
 mchk_dump_logout_frame(struct el_common *mchk_header)
 {
diff --git a/arch/alpha/kernel/err_ev6.c b/arch/alpha/kernel/err_ev6.c
index 8144f2045b5b..f12299ae1f24 100644
--- a/arch/alpha/kernel/err_ev6.c
+++ b/arch/alpha/kernel/err_ev6.c
@@ -190,6 +190,25 @@ ev6_process_logout_frame(struct el_common *mchk_header, int print)
 		(struct el_common_EV6_mcheck *)mchk_header;
 	int status = MCHK_DISPOSITION_UNKNOWN_ERROR;
 
+	/*
+	 * ES40 correctable frames end the CPU area before EXC_ADDR (Table
+	 * D-19). Validate both regions before decoding or dumping any data.
+	 */
+	if (mchk_header->proc_offset != offsetof(struct el_common_EV6_mcheck,
+					       I_STAT) ||
+	    mchk_header->sys_offset < offsetof(struct el_common_EV6_mcheck,
+					      EXC_ADDR) ||
+	    mchk_header->sys_offset > mchk_header->size ||
+	    ((mchk_header->sys_offset | mchk_header->size) & 7)) {
+		if (print) {
+			printk("%s    Invalid EV6 logout frame: size %x, CPU %x, system %x\n",
+			       err_print_prefix, mchk_header->size,
+			       mchk_header->proc_offset, mchk_header->sys_offset);
+			mchk_dump_logout_frame_raw(mchk_header);
+		}
+		return MCHK_DISPOSITION_UNKNOWN_ERROR;
+	}
+
 	status |= ev6_parse_ibox(ev6mchk->I_STAT, print);
 	status |= ev6_parse_mbox(ev6mchk->MM_STAT, ev6mchk->DC_STAT, 
 				 ev6mchk->C_STAT, print);
@@ -203,16 +222,15 @@ ev6_process_logout_frame(struct el_common *mchk_header, int print)
 	if (status != MCHK_DISPOSITION_DISMISS) {
 		char *saved_err_prefix = err_print_prefix;
 
-		/*
-		 * Dump some additional information from the frame
-		 */
-		printk("%s    EXC_ADDR: 0x%016lx   IER_CM: 0x%016lx"
-		            "   ISUM: 0x%016lx\n"
-		         "    PAL_BASE: 0x%016lx   I_CTL:  0x%016lx"
-		            "   PCTX: 0x%016lx\n",
-		       err_print_prefix,
-		       ev6mchk->EXC_ADDR, ev6mchk->IER_CM, ev6mchk->ISUM,
-		       ev6mchk->PAL_BASE, ev6mchk->I_CTL, ev6mchk->PCTX);
+		/* These registers are absent from short correctable frames. */
+		if (mchk_header->sys_offset >= sizeof(*ev6mchk))
+			printk("%s    EXC_ADDR: 0x%016lx   IER_CM: 0x%016lx"
+			       "   ISUM: 0x%016lx\n"
+			       "    PAL_BASE: 0x%016lx   I_CTL:  0x%016lx"
+			       "   PCTX: 0x%016lx\n",
+			       err_print_prefix,
+			       ev6mchk->EXC_ADDR, ev6mchk->IER_CM, ev6mchk->ISUM,
+			       ev6mchk->PAL_BASE, ev6mchk->I_CTL, ev6mchk->PCTX);
 
 		if (status == MCHK_DISPOSITION_UNKNOWN_ERROR) {
 			printk("%s    UNKNOWN error, frame follows:\n",
diff --git a/arch/alpha/kernel/err_impl.h b/arch/alpha/kernel/err_impl.h
index 737b958a586d..5bef23a00942 100644
--- a/arch/alpha/kernel/err_impl.h
+++ b/arch/alpha/kernel/err_impl.h
@@ -47,6 +47,7 @@ struct el_subpacket_handler {
 extern char *err_print_prefix;
 
 extern void mchk_dump_mem(void *, size_t, char **);
+extern void mchk_dump_logout_frame_raw(struct el_common *header);
 extern void mchk_dump_logout_frame(struct el_common *);
 extern void el_print_timestamp(union el_timestamp *);
 extern void el_process_subpackets(struct el_subpacket *, int);