From 6bebcecb6c5bf65cde18739a4fe57af25c179e44 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 3 Apr 2017 19:37:55 +0100 Subject: [PATCH] ARM: KVM: Allow the main HYP code to use the init hyp stub implementation We now have a full hyp-stub implementation in the KVM init code, but the main KVM code only supports HVC_GET_VECTORS, which is not enough. Instead of reinventing the wheel, let's reuse the init implementation by branching to the idmap page when called with a hyp-stub hypercall. Tested-by: Keerthy Acked-by: Russell King Acked-by: Catalin Marinas Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall --- arch/arm/kvm/hyp/hyp-entry.S | 29 ++++++++++++++++++++++++----- 1 file changed, 24 insertions(+), 5 deletions(-) diff --git a/arch/arm/kvm/hyp/hyp-entry.S b/arch/arm/kvm/hyp/hyp-entry.S index 1f8db7d21fc5..a35baa81fd23 100644 --- a/arch/arm/kvm/hyp/hyp-entry.S +++ b/arch/arm/kvm/hyp/hyp-entry.S @@ -126,11 +126,30 @@ hyp_hvc: */ pop {r0, r1, r2} - /* Check for __hyp_get_vectors */ - cmp r0, #HVC_GET_VECTORS - mrceq p15, 4, r0, c12, c0, 0 @ get HVBAR - beq 1f + /* + * Check if we have a kernel function, which is guaranteed to be + * bigger than the maximum hyp stub hypercall + */ + cmp r0, #HVC_STUB_HCALL_NR + bhs 1f + /* + * Not a kernel function, treat it as a stub hypercall. + * Compute the physical address for __kvm_handle_stub_hvc + * (as the code lives in the idmaped page) and branch there. + * We hijack ip (r12) as a tmp register. + */ + push {r1} + ldr r1, =kimage_voffset + ldr r1, [r1] + ldr ip, =__kvm_handle_stub_hvc + sub ip, ip, r1 +THUMB( add ip, ip, #1) + pop {r1} + + bx ip + +1: push {lr} mov lr, r0 @@ -142,7 +161,7 @@ THUMB( orr lr, #1) blx lr @ Call the HYP function pop {lr} -1: eret + eret guest_trap: load_vcpu r0 @ Load VCPU pointer to r0 -- 2.20.1