diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 420bb17440fd1653dbfde9c6f9011a5cdf94a7d8..58e69ec8b7a01ff98a0a04c8a7a6df786519eede 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -4740,6 +4740,10 @@
 			[x86] unstable: mark the TSC clocksource as unstable, this
 			marks the TSC unconditionally unstable at bootup and
 			avoids any further wobbles once the TSC watchdog notices.
+			[x86] nowatchdog: disable clocksource watchdog. Used
+			in situations with strict latency requirements (where
+			interruptions from clocksource watchdog are not
+			acceptable).
 
 	turbografx.map[2|3]=	[HW,JOY]
 			TurboGraFX parallel port interface
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index 3fae238340699376ef2b5f84d4b6d4c7f60c48c5..aab0c82e0a0d7c227b7926d92ea1eb8b590da785 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -283,6 +283,7 @@ int __init notsc_setup(char *str)
 __setup("notsc", notsc_setup);
 
 static int no_sched_irq_time;
+static int no_tsc_watchdog;
 
 static int __init tsc_setup(char *str)
 {
@@ -292,6 +293,8 @@ static int __init tsc_setup(char *str)
 		no_sched_irq_time = 1;
 	if (!strcmp(str, "unstable"))
 		mark_tsc_unstable("boot parameter");
+	if (!strcmp(str, "nowatchdog"))
+		no_tsc_watchdog = 1;
 	return 1;
 }
 
@@ -1349,7 +1352,7 @@ static int __init init_tsc_clocksource(void)
 	if (tsc_unstable)
 		goto unreg;
 
-	if (tsc_clocksource_reliable)
+	if (tsc_clocksource_reliable || no_tsc_watchdog)
 		clocksource_tsc.flags &= ~CLOCK_SOURCE_MUST_VERIFY;
 
 	if (boot_cpu_has(X86_FEATURE_NONSTOP_TSC_S3))
diff --git a/arch/x86/lib/delay.c b/arch/x86/lib/delay.c
index f5b7f1b3b6d75ce6024f7ab7459586b1f124902d..b7375dc6898f3215966359a2de29a6b8fc9ce592 100644
--- a/arch/x86/lib/delay.c
+++ b/arch/x86/lib/delay.c
@@ -162,7 +162,7 @@ void __delay(unsigned long loops)
 }
 EXPORT_SYMBOL(__delay);
 
-void __const_udelay(unsigned long xloops)
+noinline void __const_udelay(unsigned long xloops)
 {
 	unsigned long lpj = this_cpu_read(cpu_info.loops_per_jiffy) ? : loops_per_jiffy;
 	int d0;