diff --git a/tools/testing/selftests/kvm/aarch64/arch_timer.c b/tools/testing/selftests/kvm/aarch64/arch_timer.c
index 27191217f117..f794fd1152f5 100644
--- a/tools/testing/selftests/kvm/aarch64/arch_timer.c
+++ b/tools/testing/selftests/kvm/aarch64/arch_timer.c
@@ -6,16 +6,18 @@
  * CVAL and TVAL registers. This consitutes the four stages in the test.
  * The guest's main thread configures the timer interrupt for a stage
  * and waits for it to fire, with a timeout equal to the timer period.
- * It asserts that the timeout doesn't exceed the timer period.
+ * It asserts that the timeout doesn't exceed the timer period plus
+ * a user configurable error margin(default to 100us).
  *
  * On the other hand, upon receipt of an interrupt, the guest's interrupt
  * handler validates the interrupt by checking if the architectural state
  * is in compliance with the specifications.
  *
  * The test provides command-line options to configure the timer's
- * period (-p), number of vCPUs (-n), and iterations per stage (-i).
- * To stress-test the timer stack even more, an option to migrate the
- * vCPUs across pCPUs (-m), at a particular rate, is also provided.
+ * period (-p), number of vCPUs (-n), iterations per stage (-i) and timer
+ * interrupt arrival error margin (-e). To stress-test the timer stack
+ * even more, an option to migrate the vCPUs across pCPUs (-m), at a
+ * particular rate, is also provided.
  *
  * Copyright (c) 2021, Google LLC.
  */
@@ -46,6 +48,7 @@ struct test_args {
 	uint32_t nr_iter;
 	uint32_t timer_period_ms;
 	uint32_t migration_freq_ms;
+	uint32_t timer_err_margin_us;
 	struct kvm_arm_counter_offset offset;
 };
 
@@ -54,6 +57,7 @@ static struct test_args test_args = {
 	.nr_iter = NR_TEST_ITERS_DEF,
 	.timer_period_ms = TIMER_TEST_PERIOD_MS_DEF,
 	.migration_freq_ms = TIMER_TEST_MIGRATION_FREQ_MS,
+	.timer_err_margin_us = TIMER_TEST_ERR_MARGIN_US,
 	.offset = { .reserved = 1 },
 };
 
@@ -190,10 +194,14 @@ static void guest_run_stage(struct test_vcpu_shared_data *shared_data,
 
 		/* Setup a timeout for the interrupt to arrive */
 		udelay(msecs_to_usecs(test_args.timer_period_ms) +
-			TIMER_TEST_ERR_MARGIN_US);
+			test_args.timer_err_margin_us);
 
 		irq_iter = READ_ONCE(shared_data->nr_iter);
-		GUEST_ASSERT_EQ(config_iter + 1, irq_iter);
+		__GUEST_ASSERT(config_iter + 1 == irq_iter,
+				"config_iter + 1 = 0x%lx, irq_iter = 0x%lx.\n"
+				"  Guest timer interrupt was not trigged within the specified\n"
+				"  interval, try to increase the error margin by [-e] option.\n",
+				config_iter + 1, irq_iter);
 	}
 }
 
@@ -408,8 +416,9 @@ static void test_vm_cleanup(struct kvm_vm *vm)
 
 static void test_print_help(char *name)
 {
-	pr_info("Usage: %s [-h] [-n nr_vcpus] [-i iterations] [-p timer_period_ms]\n",
-		name);
+	pr_info("Usage: %s [-h] [-n nr_vcpus] [-i iterations] [-p timer_period_ms]\n"
+		"\t\t    [-m migration_freq_ms] [-o counter_offset]\n"
+		"\t\t    [-e timer_err_margin_us]\n", name);
 	pr_info("\t-n: Number of vCPUs to configure (default: %u; max: %u)\n",
 		NR_VCPUS_DEF, KVM_MAX_VCPUS);
 	pr_info("\t-i: Number of iterations per stage (default: %u)\n",
@@ -419,6 +428,8 @@ static void test_print_help(char *name)
 	pr_info("\t-m: Frequency (in ms) of vCPUs to migrate to different pCPU. 0 to turn off (default: %u)\n",
 		TIMER_TEST_MIGRATION_FREQ_MS);
 	pr_info("\t-o: Counter offset (in counter cycles, default: 0)\n");
+	pr_info("\t-e: Interrupt arrival error margin (in us) of the guest timer (default: %u)\n",
+		TIMER_TEST_ERR_MARGIN_US);
 	pr_info("\t-h: print this help screen\n");
 }
 
@@ -426,7 +437,7 @@ static bool parse_args(int argc, char *argv[])
 {
 	int opt;
 
-	while ((opt = getopt(argc, argv, "hn:i:p:m:o:")) != -1) {
+	while ((opt = getopt(argc, argv, "hn:i:p:m:o:e:")) != -1) {
 		switch (opt) {
 		case 'n':
 			test_args.nr_vcpus = atoi_positive("Number of vCPUs", optarg);
@@ -445,6 +456,9 @@ static bool parse_args(int argc, char *argv[])
 		case 'm':
 			test_args.migration_freq_ms = atoi_non_negative("Frequency", optarg);
 			break;
+		case 'e':
+			test_args.timer_err_margin_us = atoi_non_negative("Error Margin", optarg);
+			break;
 		case 'o':
 			test_args.offset.counter_offset = strtol(optarg, NULL, 0);
 			test_args.offset.reserved = 0;