[PATCH v3 02/32] KVM: arm64: Link position-independent string routines into .hyp.text

Quentin Perret
2021-03-03T16:19:25Z

From: Will Deacon <will@kernel.org>

Pull clear_page(), copy_page(), memcpy() and memset() into the nVHE hyp
code and ensure that we always execute the '__pi_' entry point on the
offchance that it changes in future.

[ qperret: Commit title nits and added linker script alias ]

Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Quentin Perret <qperret@google.com>
---
arch/arm64/include/asm/hyp_image.h | 3 +++
arch/arm64/kernel/image-vars.h | 11 +++++++++++
arch/arm64/kvm/hyp/nvhe/Makefile | 4 ++++
3 files changed, 18 insertions(+)

diff --git a/arch/arm64/include/asm/hyp_image.h b/arch/arm64/include/asm/hyp_image.h
index 737ded6b6d0d..78cd77990c9c 100644
--- a/arch/arm64/include/asm/hyp_image.h
+++ b/arch/arm64/include/asm/hyp_image.h
@@ -56,6 +56,9 @@
*/
#define KVM_NVHE_ALIAS(sym) kvm_nvhe_sym(sym) = sym;

+/* Defines a linker script alias for KVM nVHE hyp symbols */
+#define KVM_NVHE_ALIAS_HYP(first, sec) kvm_nvhe_sym(first) = kvm_nvhe_sym(sec);
+
#endif /* LINKER_SCRIPT */

#endif /* __ARM64_HYP_IMAGE_H__ */
diff --git a/arch/arm64/kernel/image-vars.h b/arch/arm64/kernel/image-vars.h
index 5aa9ed1e9ec6..4eb7a15c8b60 100644
--- a/arch/arm64/kernel/image-vars.h
+++ b/arch/arm64/kernel/image-vars.h
@@ -104,6 +104,17 @@ KVM_NVHE_ALIAS(kvm_arm_hyp_percpu_base);
/* PMU available static key */
KVM_NVHE_ALIAS(kvm_arm_pmu_available);

+/* Position-independent library routines */
+KVM_NVHE_ALIAS_HYP(clear_page, __pi_clear_page);
+KVM_NVHE_ALIAS_HYP(copy_page, __pi_copy_page);
+KVM_NVHE_ALIAS_HYP(memcpy, __pi_memcpy);
+KVM_NVHE_ALIAS_HYP(memset, __pi_memset);
+
+#ifdef CONFIG_KASAN
+KVM_NVHE_ALIAS_HYP(__memcpy, __pi_memcpy);
+KVM_NVHE_ALIAS_HYP(__memset, __pi_memset);
+#endif
+
#endif /* CONFIG_KVM */

#endif /* __ARM64_KERNEL_IMAGE_VARS_H */
diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile
index a6707df4f6c0..bc98f8e3d1da 100644
--- a/arch/arm64/kvm/hyp/nvhe/Makefile
+++ b/arch/arm64/kvm/hyp/nvhe/Makefile
@@ -9,10 +9,14 @@ ccflags-y := -D__KVM_NVHE_HYPERVISOR__ -D__DISABLE_EXPORTS
hostprogs := gen-hyprel
HOST_EXTRACFLAGS += -I$(objtree)/include

+lib-objs := clear_page.o copy_page.o memcpy.o memset.o
+lib-objs := $(addprefix ../../../lib/, $(lib-objs))
+
obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o hyp-init.o host.o \
hyp-main.o hyp-smp.o psci-relay.o
obj-y += ../vgic-v3-sr.o ../aarch32.o ../vgic-v2-cpuif-proxy.o ../entry.o \
../fpsimd.o ../hyp-entry.o ../exception.o
+obj-y += $(lib-objs)

##
## Build rules for compiling nVHE hyp code