diff --git a/arch/x86/entry/vdso/vclock_gettime.c b/arch/x86/entry/vdso/vclock_gettime.c
index 5dd363d54348..722cbed8026b 100644
--- a/arch/x86/entry/vdso/vclock_gettime.c
+++ b/arch/x86/entry/vdso/vclock_gettime.c
@@ -51,8 +51,9 @@ extern u8 pvclock_page
 notrace static long vdso_fallback_gettime(long clock, struct timespec *ts)
 {
 	long ret;
-	asm("syscall" : "=a" (ret) :
-	    "0" (__NR_clock_gettime), "D" (clock), "S" (ts) : "memory");
+	asm ("syscall" : "=a" (ret), "=m" (*ts) :
+	     "0" (__NR_clock_gettime), "D" (clock), "S" (ts) :
+	     "memory", "rcx", "r11");
 	return ret;
 }
 
@@ -60,8 +61,9 @@ notrace static long vdso_fallback_gtod(struct timeval *tv, struct timezone *tz)
 {
 	long ret;
 
-	asm("syscall" : "=a" (ret) :
-	    "0" (__NR_gettimeofday), "D" (tv), "S" (tz) : "memory");
+	asm ("syscall" : "=a" (ret), "=m" (*tv), "=m" (*tz) :
+	     "0" (__NR_gettimeofday), "D" (tv), "S" (tz) :
+	     "memory", "rcx", "r11");
 	return ret;
 }
 
@@ -143,12 +145,12 @@ notrace static long vdso_fallback_gettime(long clock, struct timespec *ts)
 {
 	long ret;
 
-	asm(
+	asm (
 		"mov %%ebx, %%edx \n"
 		"mov %2, %%ebx \n"
 		"call __kernel_vsyscall \n"
 		"mov %%edx, %%ebx \n"
-		: "=a" (ret)
+		: "=a" (ret), "=m" (*ts)
 		: "0" (__NR_clock_gettime), "g" (clock), "c" (ts)
 		: "memory", "edx");
 	return ret;
@@ -158,12 +160,12 @@ notrace static long vdso_fallback_gtod(struct timeval *tv, struct timezone *tz)
 {
 	long ret;
 
-	asm(
+	asm (
 		"mov %%ebx, %%edx \n"
 		"mov %2, %%ebx \n"
 		"call __kernel_vsyscall \n"
 		"mov %%edx, %%ebx \n"
-		: "=a" (ret)
+		: "=a" (ret), "=m" (*tv), "=m" (*tz)
 		: "0" (__NR_gettimeofday), "g" (tv), "c" (tz)
 		: "memory", "edx");
 	return ret;