linux-kernel - [PATCH v5 21/36] KVM: arm64: Set host stage 2 using kvm_nvhe_init

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20210315143536.214621-22-qperret@google.com>
Date:   Mon, 15 Mar 2021 14:35:21 +0000
From:   Quentin Perret <qperret@...gle.com>
To:     catalin.marinas@....com, will@...nel.org, maz@...nel.org,
        james.morse@....com, julien.thierry.kdev@...il.com,
        suzuki.poulose@....com
Cc:     android-kvm@...gle.com, seanjc@...gle.com, mate.toth-pal@....com,
        linux-kernel@...r.kernel.org, robh+dt@...nel.org,
        linux-arm-kernel@...ts.infradead.org, kernel-team@...roid.com,
        kvmarm@...ts.cs.columbia.edu, tabba@...gle.com, ardb@...nel.org,
        mark.rutland@....com, dbrazdil@...gle.com, qperret@...gle.com
Subject: [PATCH v5 21/36] KVM: arm64: Set host stage 2 using kvm_nvhe_init_params

Move the registers relevant to host stage 2 enablement to
kvm_nvhe_init_params to prepare the ground for enabling it in later
patches.

Acked-by: Will Deacon <will@...nel.org>
Signed-off-by: Quentin Perret <qperret@...gle.com>
---
 arch/arm64/include/asm/kvm_asm.h   |  3 +++
 arch/arm64/kernel/asm-offsets.c    |  3 +++
 arch/arm64/kvm/arm.c               |  5 +++++
 arch/arm64/kvm/hyp/nvhe/hyp-init.S | 14 +++++++++-----
 arch/arm64/kvm/hyp/nvhe/switch.c   |  5 +----
 5 files changed, 21 insertions(+), 9 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index db20a9477870..6dce860f8bca 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -158,6 +158,9 @@ struct kvm_nvhe_init_params {
 	unsigned long tpidr_el2;
 	unsigned long stack_hyp_va;
 	phys_addr_t pgd_pa;
+	unsigned long hcr_el2;
+	unsigned long vttbr;
+	unsigned long vtcr;
 };
 
 /* Translate a kernel address @ptr into its equivalent linear mapping */
diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c
index a36e2fc330d4..8930b42f6418 100644
--- a/arch/arm64/kernel/asm-offsets.c
+++ b/arch/arm64/kernel/asm-offsets.c
@@ -120,6 +120,9 @@ int main(void)
   DEFINE(NVHE_INIT_TPIDR_EL2,	offsetof(struct kvm_nvhe_init_params, tpidr_el2));
   DEFINE(NVHE_INIT_STACK_HYP_VA,	offsetof(struct kvm_nvhe_init_params, stack_hyp_va));
   DEFINE(NVHE_INIT_PGD_PA,	offsetof(struct kvm_nvhe_init_params, pgd_pa));
+  DEFINE(NVHE_INIT_HCR_EL2,	offsetof(struct kvm_nvhe_init_params, hcr_el2));
+  DEFINE(NVHE_INIT_VTTBR,	offsetof(struct kvm_nvhe_init_params, vttbr));
+  DEFINE(NVHE_INIT_VTCR,	offsetof(struct kvm_nvhe_init_params, vtcr));
 #endif
 #ifdef CONFIG_CPU_PM
   DEFINE(CPU_CTX_SP,		offsetof(struct cpu_suspend_ctx, sp));
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 7d62211109d9..d474eec606a3 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -1413,6 +1413,11 @@ static void cpu_prepare_hyp_mode(int cpu)
 
 	params->stack_hyp_va = kern_hyp_va(per_cpu(kvm_arm_hyp_stack_page, cpu) + PAGE_SIZE);
 	params->pgd_pa = kvm_mmu_get_httbr();
+	if (is_protected_kvm_enabled())
+		params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS;
+	else
+		params->hcr_el2 = HCR_HOST_NVHE_FLAGS;
+	params->vttbr = params->vtcr = 0;
 
 	/*
 	 * Flush the init params from the data cache because the struct will
diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-init.S b/arch/arm64/kvm/hyp/nvhe/hyp-init.S
index a2b8b6a84cbd..a50ad9e9fc05 100644
--- a/arch/arm64/kvm/hyp/nvhe/hyp-init.S
+++ b/arch/arm64/kvm/hyp/nvhe/hyp-init.S
@@ -83,11 +83,6 @@ SYM_CODE_END(__kvm_hyp_init)
  * x0: struct kvm_nvhe_init_params PA
  */
 SYM_CODE_START_LOCAL(___kvm_hyp_init)
-alternative_if ARM64_KVM_PROTECTED_MODE
-	mov_q	x1, HCR_HOST_NVHE_PROTECTED_FLAGS
-	msr	hcr_el2, x1
-alternative_else_nop_endif
-
 	ldr	x1, [x0, #NVHE_INIT_TPIDR_EL2]
 	msr	tpidr_el2, x1
 
@@ -97,6 +92,15 @@ alternative_else_nop_endif
 	ldr	x1, [x0, #NVHE_INIT_MAIR_EL2]
 	msr	mair_el2, x1
 
+	ldr	x1, [x0, #NVHE_INIT_HCR_EL2]
+	msr	hcr_el2, x1
+
+	ldr	x1, [x0, #NVHE_INIT_VTTBR]
+	msr	vttbr_el2, x1
+
+	ldr	x1, [x0, #NVHE_INIT_VTCR]
+	msr	vtcr_el2, x1
+
 	ldr	x1, [x0, #NVHE_INIT_PGD_PA]
 	phys_to_ttbr x2, x1
 alternative_if ARM64_HAS_CNP
diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c
index f3d0e9eca56c..979a76cdf9fb 100644
--- a/arch/arm64/kvm/hyp/nvhe/switch.c
+++ b/arch/arm64/kvm/hyp/nvhe/switch.c
@@ -97,10 +97,7 @@ static void __deactivate_traps(struct kvm_vcpu *vcpu)
 	mdcr_el2 |= MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT;
 
 	write_sysreg(mdcr_el2, mdcr_el2);
-	if (is_protected_kvm_enabled())
-		write_sysreg(HCR_HOST_NVHE_PROTECTED_FLAGS, hcr_el2);
-	else
-		write_sysreg(HCR_HOST_NVHE_FLAGS, hcr_el2);
+	write_sysreg(this_cpu_ptr(&kvm_init_params)->hcr_el2, hcr_el2);
 	write_sysreg(CPTR_EL2_DEFAULT, cptr_el2);
 	write_sysreg(__kvm_hyp_host_vector, vbar_el2);
 }
-- 
2.31.0.rc2.261.g7f71774620-goog