KVM: arm64: Avoid unnecessary absolute addressing via literals
authorArd Biesheuvel <ardb@kernel.org>
Thu, 28 Apr 2022 14:03:50 +0000 (16:03 +0200)
committerMarc Zyngier <maz@kernel.org>
Fri, 6 May 2022 10:03:56 +0000 (11:03 +0100)
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
arch/arm64/kvm/hyp/nvhe/host.S

index 3d613e7..3665515 100644 (file)
@@ -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)