Directly using the kimage_voffset variable is fine for now, but will become more problematic as we start distrusting EL1. Instead, patch the kimage_voffset into the HYP text, ensuring we don't have to load an untrusted value later on. Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx> --- arch/arm64/kernel/image-vars.h | 4 +--- arch/arm64/kvm/hyp/nvhe/host.S | 7 ++++++- arch/arm64/kvm/va_layout.c | 6 ++++++ 3 files changed, 13 insertions(+), 4 deletions(-) diff --git a/arch/arm64/kernel/image-vars.h b/arch/arm64/kernel/image-vars.h index b5b0fdd1043c..259c704a548a 100644 --- a/arch/arm64/kernel/image-vars.h +++ b/arch/arm64/kernel/image-vars.h @@ -65,13 +65,11 @@ __efistub__ctype = _ctype; KVM_NVHE_ALIAS(kvm_patch_vector_branch); KVM_NVHE_ALIAS(kvm_update_va_mask); KVM_NVHE_ALIAS(kvm_update_kimg_phys_offset); +KVM_NVHE_ALIAS(kvm_get_kimage_voffset); /* Global kernel state accessed by nVHE hyp code. */ KVM_NVHE_ALIAS(kvm_vgic_global_state); -/* Kernel constant needed to compute idmap addresses. */ -KVM_NVHE_ALIAS(kimage_voffset); - /* Kernel symbols used to call panic() from nVHE hyp code (via ERET). */ KVM_NVHE_ALIAS(__hyp_panic_string); KVM_NVHE_ALIAS(panic); diff --git a/arch/arm64/kvm/hyp/nvhe/host.S b/arch/arm64/kvm/hyp/nvhe/host.S index ed27f06a31ba..e2d316d13180 100644 --- a/arch/arm64/kvm/hyp/nvhe/host.S +++ b/arch/arm64/kvm/hyp/nvhe/host.S @@ -115,7 +115,12 @@ SYM_FUNC_END(__hyp_do_panic) * Preserve x0-x4, which may contain stub parameters. */ ldr x5, =__kvm_handle_stub_hvc - ldr_l x6, kimage_voffset +alternative_cb kvm_get_kimage_voffset + movz x6, #0 + movk x6, #0, lsl #16 + movk x6, #0, lsl #32 + movk x6, #0, lsl #48 +alternative_cb_end /* x5 = __pa(x5) */ sub x5, x5, x6 diff --git a/arch/arm64/kvm/va_layout.c b/arch/arm64/kvm/va_layout.c index 1d00d2cb93fd..d61117805de0 100644 --- a/arch/arm64/kvm/va_layout.c +++ b/arch/arm64/kvm/va_layout.c @@ -251,3 +251,9 @@ void kvm_update_kimg_phys_offset(struct alt_instr *alt, { generate_mov_q(kimage_voffset + PHYS_OFFSET, origptr, updptr, nr_inst); } + +void kvm_get_kimage_voffset(struct alt_instr *alt, + __le32 *origptr, __le32 *updptr, int nr_inst) +{ + generate_mov_q(kimage_voffset, origptr, updptr, nr_inst); +} -- 2.28.0 _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm