diff --git a/src/arch/x86/transitions/librm.S b/src/arch/x86/transitions/librm.S
index e91ede37..c31daad8 100644
--- a/src/arch/x86/transitions/librm.S
+++ b/src/arch/x86/transitions/librm.S
@@ -7,6 +7,9 @@
 
 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL )
 
+/* Drag in general configuration */
+#include <config/general.h>
+
 /* Drag in local definitions */
 #include "librm.h"
 
@@ -207,7 +210,9 @@ VC_TMP_CR3:		.space	4
 VC_TMP_CR4:		.space	4
 VC_TMP_EMER:		.space	8
 .endif
+#ifdef TIVOLI_VMM_WORKAROUND
 VC_TMP_FXSAVE:		.space	512
+#endif
 VC_TMP_END:
 	.previous
 
@@ -1000,11 +1005,12 @@ virt_call:
 
 	/* Claim ownership of temporary static buffer */
 	cli
-
-	/* Preserve FPU, MMX and SSE state in temporary static buffer */
 	movw	%cs:rm_ds, %ds
-	fxsave	( rm_tmpbuf + VC_TMP_FXSAVE )
 
+#ifdef TIVOLI_VMM_WORKAROUND
+	/* Preserve FPU, MMX and SSE state in temporary static buffer */
+	fxsave	( rm_tmpbuf + VC_TMP_FXSAVE )
+#endif
 	/* Preserve GDT and IDT in temporary static buffer */
 	sidt	( rm_tmpbuf + VC_TMP_IDT )
 	sgdt	( rm_tmpbuf + VC_TMP_GDT )
@@ -1070,9 +1076,11 @@ vc_rmode:
 	movl	$MSR_EFER, %ecx
 	wrmsr
 .endif
+
+#ifdef TIVOLI_VMM_WORKAROUND
 	/* Restore FPU, MMX and SSE state from temporary static buffer */
 	fxrstor	( rm_tmpbuf + VC_TMP_FXSAVE )
-
+#endif
 	/* Restore registers and flags and return */
 	popl	%eax /* skip %cs and %ss */
 	popw	%ds
diff --git a/src/config/general.h b/src/config/general.h
index d2bbeb06..be0845f6 100644
--- a/src/config/general.h
+++ b/src/config/general.h
@@ -190,6 +190,9 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 #undef	GDBUDP			/* Remote GDB debugging over UDP
 				 * (both may be set) */
 //#define EFI_DOWNGRADE_UX	/* Downgrade UEFI user experience */
+#define	TIVOLI_VMM_WORKAROUND	/* Work around the Tivoli VMM's garbling of SSE
+				 * registers when iPXE traps to it due to
+				 * privileged instructions */
 
 #include <config/named.h>
 #include NAMED_CONFIG(general.h)