From 50d912cc3e5055c14e13a8e7de5c078b01a2e2b7 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 3 Apr 2017 19:37:34 +0100 Subject: arm64: hyp-stub: Stop pointlessly clobbering lr When entering the kernel hyp stub, we check whether or not we've made it here through an HVC instruction, clobbering lr (aka x30) in the process. This is completely pointless, as HVC is the only way to get here (all traps to EL2 are disabled, no interrupt override is applied). So let's remove this bit of code whose only point is to corrupt a valuable register. Acked-by: Catalin Marinas Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall --- arch/arm64/kernel/hyp-stub.S | 6 ------ 1 file changed, 6 deletions(-) diff --git a/arch/arm64/kernel/hyp-stub.S b/arch/arm64/kernel/hyp-stub.S index d3b5f75e652e..e4215ad06930 100644 --- a/arch/arm64/kernel/hyp-stub.S +++ b/arch/arm64/kernel/hyp-stub.S @@ -55,12 +55,6 @@ ENDPROC(__hyp_stub_vectors) .align 11 el1_sync: - mrs x30, esr_el2 - lsr x30, x30, #ESR_ELx_EC_SHIFT - - cmp x30, #ESR_ELx_EC_HVC64 - b.ne 9f // Not an HVC trap - cmp x0, #HVC_GET_VECTORS b.ne 1f mrs x0, vbar_el2 -- cgit v1.2.3-59-g8ed1b