[RFC PATCH 4/6] kvm: arm64: Remove patching of fn pointers in hyp
From: David Brazdil
Date: Thu Nov 19 2020 - 11:26:12 EST
Taking a function pointer will now generate a R_AARCH64_RELATIVE that is
fixed up at early boot. Remove the alternative-based mechanism for
converting the address from a kernel VA.
Signed-off-by: David Brazdil <dbrazdil@xxxxxxxxxx>
---
arch/arm64/include/asm/kvm_mmu.h | 18 ------------------
arch/arm64/kernel/image-vars.h | 1 -
arch/arm64/kvm/hyp/nvhe/hyp-main.c | 11 ++++-------
arch/arm64/kvm/va_layout.c | 6 ------
4 files changed, 4 insertions(+), 32 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
index e5226f7e4732..8cb8974ec9cc 100644
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h
@@ -121,24 +121,6 @@ static __always_inline unsigned long __kern_hyp_va(unsigned long v)
#define kern_hyp_va(v) ((typeof(v))(__kern_hyp_va((unsigned long)(v))))
-static __always_inline unsigned long __kimg_hyp_va(unsigned long v)
-{
- unsigned long offset;
-
- asm volatile(ALTERNATIVE_CB("movz %0, #0\n"
- "movk %0, #0, lsl #16\n"
- "movk %0, #0, lsl #32\n"
- "movk %0, #0, lsl #48\n",
- kvm_update_kimg_phys_offset)
- : "=r" (offset));
-
- return __kern_hyp_va((v - offset) | PAGE_OFFSET);
-}
-
-#define kimg_fn_hyp_va(v) ((typeof(*v))(__kimg_hyp_va((unsigned long)(v))))
-
-#define kimg_fn_ptr(x) (typeof(x) **)(x)
-
/*
* We currently support using a VM-specified IPA size. For backward
* compatibility, the default IPA size is fixed to 40bits.
diff --git a/arch/arm64/kernel/image-vars.h b/arch/arm64/kernel/image-vars.h
index 8539f34d7538..6379721236cf 100644
--- a/arch/arm64/kernel/image-vars.h
+++ b/arch/arm64/kernel/image-vars.h
@@ -64,7 +64,6 @@ __efistub__ctype = _ctype;
/* Alternative callbacks for init-time patching of nVHE hyp code. */
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. */
diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c
index b3db5f4eea27..7998eff5f0a2 100644
--- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c
+++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c
@@ -110,9 +110,9 @@ static void handle___vgic_v3_restore_aprs(struct kvm_cpu_context *host_ctxt)
typedef void (*hcall_t)(struct kvm_cpu_context *);
-#define HANDLE_FUNC(x) [__KVM_HOST_SMCCC_FUNC_##x] = kimg_fn_ptr(handle_##x)
+#define HANDLE_FUNC(x) [__KVM_HOST_SMCCC_FUNC_##x] = (hcall_t)handle_##x
-static const hcall_t *host_hcall[] = {
+static const hcall_t host_hcall[] = {
HANDLE_FUNC(__kvm_vcpu_run),
HANDLE_FUNC(__kvm_flush_vm_context),
HANDLE_FUNC(__kvm_tlb_flush_vmid_ipa),
@@ -132,7 +132,6 @@ static const hcall_t *host_hcall[] = {
static void handle_host_hcall(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(unsigned long, id, host_ctxt, 0);
- const hcall_t *kfn;
hcall_t hfn;
id -= KVM_HOST_SMCCC_ID(0);
@@ -140,13 +139,11 @@ static void handle_host_hcall(struct kvm_cpu_context *host_ctxt)
if (unlikely(id >= ARRAY_SIZE(host_hcall)))
goto inval;
- kfn = host_hcall[id];
- if (unlikely(!kfn))
+ hfn = host_hcall[id];
+ if (unlikely(!hfn))
goto inval;
cpu_reg(host_ctxt, 0) = SMCCC_RET_SUCCESS;
-
- hfn = kimg_fn_hyp_va(kfn);
hfn(host_ctxt);
return;
diff --git a/arch/arm64/kvm/va_layout.c b/arch/arm64/kvm/va_layout.c
index 7f45a98eacfd..0494315f71f2 100644
--- a/arch/arm64/kvm/va_layout.c
+++ b/arch/arm64/kvm/va_layout.c
@@ -373,12 +373,6 @@ static void generate_mov_q(u64 val, __le32 *origptr, __le32 *updptr, int nr_inst
*updptr++ = cpu_to_le32(insn);
}
-void kvm_update_kimg_phys_offset(struct alt_instr *alt,
- __le32 *origptr, __le32 *updptr, int nr_inst)
-{
- 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)
{
--
2.29.2.299.gdc1121823c-goog