diff --git a/sys/amd64/acpica/acpi_switch.S b/sys/amd64/acpica/acpi_switch.S
index 0b262925d2f6..2274c85ec547 100644
--- a/sys/amd64/acpica/acpi_switch.S
+++ b/sys/amd64/acpica/acpi_switch.S
@@ -128,9 +128,19 @@ ENTRY(acpi_restorecpu)
 	/* Restore descriptor tables. */
 	lidt	WAKEUP_XPCB(IDT)
 	lldt	WAKEUP_XPCB(LDT)
+
+#define	SDT_SYSTSS	9
+#define	SDT_SYSBSY	11
+
+	/* Reset task busy bit and reload TR. */
+	movq	PCPU(TSS), %rax
+	andb	$(~SDT_SYSBSY | SDT_SYSTSS), 5(%rax)
 	movw	WAKEUP_XPCB(TR), %ax
 	ltr	%ax
 
+#undef	SDT_SYSTSS
+#undef	SDT_SYSBSY
+
 	/* Restore other callee saved registers. */
 	movq	WAKEUP_PCB(R15), %r15
 	movq	WAKEUP_PCB(R14), %r14
diff --git a/sys/amd64/acpica/acpi_wakecode.S b/sys/amd64/acpica/acpi_wakecode.S
index 4165ec68867d..4e82f53196af 100644
--- a/sys/amd64/acpica/acpi_wakecode.S
+++ b/sys/amd64/acpica/acpi_wakecode.S
@@ -223,6 +223,12 @@ reset_video:
 bootgdt:
 	.long	0x00000000
 	.long	0x00000000
+	.long	0x00000000
+	.long	0x00000000
+	.long	0x00000000
+	.long	0x00000000
+	.long	0x00000000
+	.long	0x00000000
 
 bootcode64:
 	.long	0x0000ffff
@@ -261,6 +267,8 @@ wakeup_xpcb:
 wakeup_gdt:
 	.word	0
 	.quad	0
+
+	ALIGN_DATA
 wakeup_efer:
 	.quad	0
 wakeup_pat:
diff --git a/sys/amd64/acpica/acpi_wakeup.c b/sys/amd64/acpica/acpi_wakeup.c
index 02432f0d983b..2f9d8a01b295 100644
--- a/sys/amd64/acpica/acpi_wakeup.c
+++ b/sys/amd64/acpica/acpi_wakeup.c
@@ -78,7 +78,6 @@ static struct xpcb	*stopxpcbs;
 int			acpi_restorecpu(struct xpcb *, vm_offset_t);
 int			acpi_savecpu(struct xpcb *);
 
-static void		acpi_reset_tss(int cpu);
 static void		acpi_alloc_wakeup_handler(void);
 static void		acpi_stop_beep(void *);
 
@@ -116,8 +115,6 @@ acpi_wakeup_ap(struct acpi_softc *sc, int cpu)
 	    stopxpcbs[cpu].xpcb_gdt.rd_base);
 	WAKECODE_FIXUP(wakeup_cpu, int, cpu);
 
-	acpi_reset_tss(cpu);
-
 	/* do an INIT IPI: assert RESET */
 	lapic_ipi_raw(APIC_DEST_DESTFLD | APIC_TRIGMOD_EDGE |
 	    APIC_LEVEL_ASSERT | APIC_DESTMODE_PHY | APIC_DELMODE_INIT, apic_id);
@@ -220,19 +217,6 @@ acpi_wakeup_cpus(struct acpi_softc *sc, cpumask_t wakeup_cpus)
 }
 #endif
 
-static void
-acpi_reset_tss(int cpu)
-{
-	uint32_t	*tss;
-
-	/*
-	 * We have to clear "task busy" bit in TSS to restore
-	 * task register later.  Otherwise, ltr causes GPF.
-	 */
-	tss = (uint32_t *)&gdt[NGDT * cpu + GPROC0_SEL] + 1;
-	*tss &= ~((SDT_SYSBSY ^ SDT_SYSTSS) << 8);
-}
-
 int
 acpi_sleep_machdep(struct acpi_softc *sc, int state)
 {
@@ -289,8 +273,6 @@ acpi_sleep_machdep(struct acpi_softc *sc, int state)
 		    stopxpcbs[0].xpcb_gdt.rd_base);
 		WAKECODE_FIXUP(wakeup_cpu, int, 0);
 
-		acpi_reset_tss(0);
-
 		/* Call ACPICA to enter the desired sleep state */
 		if (state == ACPI_STATE_S4 && sc->acpi_s4bios)
 			status = AcpiEnterSleepStateS4bios();