From f1bca539a17f917ed3e0f92ab78f38584df7fe6e Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 22 Mar 2021 12:09:51 +0000 Subject: [PATCH] FROMGIT: KVM: arm64: Generate final CTR_EL0 value when running in Protected mode In protected mode, late CPUs are not allowed to boot (enforced by the PSCI relay). We can thus specialise the read_ctr macro to always return a pre-computed, sanitised value. Special care is taken to prevent the use of this custome version outside of the protected mode. Bug: 178098380 Reviewed-by: Quentin Perret Signed-off-by: Marc Zyngier (cherry picked from commit 755db23420a1ce4b740186543432983e9bbe713e git//git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm.git next) Signed-off-by: Quentin Perret Change-Id: I70832065d8f4d76cb5e1c6e1d326e585e877d35c --- arch/arm64/include/asm/assembler.h | 13 +++++++++++++ arch/arm64/kernel/image-vars.h | 1 + arch/arm64/kvm/va_layout.c | 7 +++++++ 3 files changed, 21 insertions(+) diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index ac4e833a559f..2bce4e17dc22 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -15,6 +15,7 @@ #include #include +#include #include #include #include @@ -270,12 +271,24 @@ alternative_endif * provide the system wide safe value from arm64_ftr_reg_ctrel0.sys_val */ .macro read_ctr, reg +#ifndef __KVM_NVHE_HYPERVISOR__ alternative_if_not ARM64_MISMATCHED_CACHE_TYPE mrs \reg, ctr_el0 // read CTR nop alternative_else ldr_l \reg, arm64_ftr_reg_ctrel0 + ARM64_FTR_SYSVAL alternative_endif +#else +alternative_if_not ARM64_KVM_PROTECTED_MODE + ASM_BUG() +alternative_else_nop_endif +alternative_cb kvm_compute_final_ctr_el0 + movz \reg, #0 + movk \reg, #0, lsl #16 + movk \reg, #0, lsl #32 + movk \reg, #0, lsl #48 +alternative_cb_end +#endif .endm diff --git a/arch/arm64/kernel/image-vars.h b/arch/arm64/kernel/image-vars.h index d5dc2b792651..fdd60cd1d7e8 100644 --- a/arch/arm64/kernel/image-vars.h +++ b/arch/arm64/kernel/image-vars.h @@ -65,6 +65,7 @@ __efistub__ctype = _ctype; KVM_NVHE_ALIAS(kvm_patch_vector_branch); KVM_NVHE_ALIAS(kvm_update_va_mask); KVM_NVHE_ALIAS(kvm_get_kimage_voffset); +KVM_NVHE_ALIAS(kvm_compute_final_ctr_el0); /* Global kernel state accessed by nVHE hyp code. */ KVM_NVHE_ALIAS(kvm_vgic_global_state); diff --git a/arch/arm64/kvm/va_layout.c b/arch/arm64/kvm/va_layout.c index 978301392d67..acdb7b3cc97d 100644 --- a/arch/arm64/kvm/va_layout.c +++ b/arch/arm64/kvm/va_layout.c @@ -288,3 +288,10 @@ void kvm_get_kimage_voffset(struct alt_instr *alt, { generate_mov_q(kimage_voffset, origptr, updptr, nr_inst); } + +void kvm_compute_final_ctr_el0(struct alt_instr *alt, + __le32 *origptr, __le32 *updptr, int nr_inst) +{ + generate_mov_q(read_sanitised_ftr_reg(SYS_CTR_EL0), + origptr, updptr, nr_inst); +}