Commit 7ee74cc7 authored Apr 28, 2022 by Ard Biesheuvel Committed by Marc Zyngier May 06, 2022

KVM: arm64: Avoid unnecessary absolute addressing via literals

There are a few cases in the nVHE code where we take the absolute
address of a symbol via a literal pool entry, and subsequently translate
it to another address space (PA, kimg VA, kernel linear VA, etc).
Originally, this literal was needed because we relied on a different
translation for absolute references, but this is no longer the case, so
we can simply use relative addressing instead. This removes a couple of
RELA entries pointing into the .text segment.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220428140350.3303481-1-ardb@kernel.org

parent 325031d4

arch/arm64/kvm/hyp/nvhe/host.S

+3 −5

Original line number	Diff line number	Diff line
		@@ -80,7 +80,7 @@ SYM_FUNC_START(__hyp_do_panic)
		mov lr, #(PSR_F_BIT \| PSR_I_BIT \| PSR_A_BIT \| PSR_D_BIT \|\
		PSR_MODE_EL1h)
		msr spsr_el2, lr
		ldr lr, =nvhe_hyp_panic_handler
		adr_l lr, nvhe_hyp_panic_handler
		hyp_kimg_va lr, x6
		msr elr_el2, lr

		@@ -125,13 +125,11 @@ alternative_else_nop_endif
		add sp, sp, #16
		/*
		* Compute the idmap address of __kvm_handle_stub_hvc and
		* jump there. Since we use kimage_voffset, do not use the
		* HYP VA for __kvm_handle_stub_hvc, but the kernel VA instead
		* (by loading it from the constant pool).
		* jump there.
		*
		* Preserve x0-x4, which may contain stub parameters.
		*/
		ldr x5, =__kvm_handle_stub_hvc
		adr_l x5, __kvm_handle_stub_hvc
		hyp_pa x5, x6
		br x5
		SYM_FUNC_END(__host_hvc)