ARM: KVM: clear exclusive monitor on all exception returns

commit 22cfbb6d upstream.

Make sure we clear the exclusive monitor on all exception returns,
which otherwise could lead to lock corruptions.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Jonghwan Choi <jhbird.choi@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/arm/kvm/interrupts.S

@@ -292,6 +292,7 @@ THUMB(	orr	r2, r2, #PSR_T_BIT	)
 	ldr	r2, =BSYM(panic)
 	msr	ELR_hyp, r2
 	ldr	r0, =\panic_str
+	clrex				@ Clear exclusive monitor
 	eret
 .endm
 
@@ -441,6 +442,7 @@ guest_trap:
 
 4:	pop	{r0, r1}		@ Failed translation, return to guest
 	mcrr	p15, 0, r0, r1, c7	@ PAR
+	clrex
 	pop	{r0, r1, r2}
 	eret
 
@@ -467,6 +469,7 @@ switch_to_guest_vfp:
 
 	pop	{r3-r7}
 	pop	{r0-r2}
+	clrex
 	eret
 #endif