diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h
index f1662df255caf45d024b429055dc48eee2e90cb4..408bc4719f3b24eec2f95b15afb5e2c827748810 100644
--- a/arch/arm64/include/asm/ptrace.h
+++ b/arch/arm64/include/asm/ptrace.h
@@ -27,6 +27,11 @@
 #define CurrentEL_EL1		(1 << 2)
 #define CurrentEL_EL2		(2 << 2)
 
+#define INIT_PSTATE_EL1 \
+	(PSR_D_BIT | PSR_A_BIT | PSR_I_BIT | PSR_F_BIT | PSR_MODE_EL1h)
+#define INIT_PSTATE_EL2 \
+	(PSR_D_BIT | PSR_A_BIT | PSR_I_BIT | PSR_F_BIT | PSR_MODE_EL2h)
+
 /*
  * PMR values used to mask/unmask interrupts.
  *
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index 9f083b11efe255855e99fe625bc6717002363d93..04dc533ea8b6035319d27f40d6686e7173acb625 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -465,19 +465,24 @@ ENTRY(kimage_vaddr)
  * If we're fortunate enough to boot at EL2, ensure that the world is
  * sane before dropping to EL1.
  *
+ * Since we cannot always rely on ERET synchronizing writes to sysregs (e.g. if
+ * SCTLR_ELx.EOS is clear), we place an ISB prior to ERET.
+ *
  * Returns either BOOT_CPU_MODE_EL1 or BOOT_CPU_MODE_EL2 in w0 if
  * booted in EL1 or EL2 respectively.
  */
 ENTRY(el2_setup)
-	msr	SPsel, #1			// We want to use SP_EL{1,2}
 	mrs	x0, CurrentEL
 	cmp	x0, #CurrentEL_EL2
 	b.eq	1f
 	mov_q	x0, (SCTLR_EL1_RES1 | ENDIAN_SET_EL1)
 	msr	sctlr_el1, x0
-	mov	w0, #BOOT_CPU_MODE_EL1		// This cpu booted in EL1
 	isb
-	ret
+	mov_q	x0, INIT_PSTATE_EL1
+	msr	spsr_el1, x0
+	msr	elr_el1, lr
+	mov	w0, #BOOT_CPU_MODE_EL1
+	eret
 
 1:	mov_q	x0, (SCTLR_EL2_RES1 | ENDIAN_SET_EL2)
 	msr	sctlr_el2, x0
@@ -588,9 +593,12 @@ set_hcr:
 
 	cbz	x2, install_el2_stub
 
-	mov	w0, #BOOT_CPU_MODE_EL2		// This CPU booted in EL2
 	isb
-	ret
+	mov_q	x0, INIT_PSTATE_EL2
+	msr	spsr_el2, x0
+	msr	elr_el2, lr
+	mov	w0, #BOOT_CPU_MODE_EL2
+	eret
 
 install_el2_stub:
 	/*
@@ -622,12 +630,11 @@ install_el2_stub:
 7:	adr_l	x0, __hyp_stub_vectors
 	msr	vbar_el2, x0
 
-	/* spsr */
-	mov	x0, #(PSR_F_BIT | PSR_I_BIT | PSR_A_BIT | PSR_D_BIT |\
-		      PSR_MODE_EL1h)
+	isb
+	mov	x0, #INIT_PSTATE_EL1
 	msr	spsr_el2, x0
 	msr	elr_el2, lr
-	mov	w0, #BOOT_CPU_MODE_EL2		// This CPU booted in EL2
+	mov	w0, #BOOT_CPU_MODE_EL2
 	eret
 ENDPROC(el2_setup)