From: Fuad Tabba <tabba@google.com>
To: kvmarm@lists.cs.columbia.edu
Cc: maz@kernel.org, will@kernel.org, james.morse@arm.com,
alexandru.elisei@arm.com, suzuki.poulose@arm.com,
mark.rutland@arm.com, christoffer.dall@arm.com,
pbonzini@redhat.com, drjones@redhat.com, qperret@google.com,
kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
kernel-team@android.com, tabba@google.com
Subject: [PATCH v3 06/15] KVM: arm64: Restore mdcr_el2 from vcpu
Date: Mon, 19 Jul 2021 17:03:37 +0100 [thread overview]
Message-ID: <20210719160346.609914-7-tabba@google.com> (raw)
In-Reply-To: <20210719160346.609914-1-tabba@google.com>
On deactivating traps, restore the value of mdcr_el2 from the
newly created and preserved host value vcpu context, rather than
directly reading the hardware register.
Up until and including this patch the two values are the same,
i.e., the hardware register and the vcpu one. A future patch will
be changing the value of mdcr_el2 on activating traps, and this
ensures that its value will be restored.
No functional change intended.
Signed-off-by: Fuad Tabba <tabba@google.com>
---
arch/arm64/include/asm/kvm_host.h | 5 ++++-
arch/arm64/include/asm/kvm_hyp.h | 2 +-
arch/arm64/kvm/hyp/include/hyp/switch.h | 6 +++++-
arch/arm64/kvm/hyp/nvhe/switch.c | 11 ++---------
arch/arm64/kvm/hyp/vhe/switch.c | 12 ++----------
arch/arm64/kvm/hyp/vhe/sysreg-sr.c | 2 +-
6 files changed, 15 insertions(+), 23 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 4d2d974c1522..76462c6a91ee 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -287,10 +287,13 @@ struct kvm_vcpu_arch {
/* Stage 2 paging state used by the hardware on next switch */
struct kvm_s2_mmu *hw_mmu;
- /* HYP configuration */
+ /* Values of trap registers for the guest. */
u64 hcr_el2;
u64 mdcr_el2;
+ /* Values of trap registers for the host before guest entry. */
+ u64 mdcr_el2_host;
+
/* Exception Information */
struct kvm_vcpu_fault_info fault;
diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h
index 9d60b3006efc..657d0c94cf82 100644
--- a/arch/arm64/include/asm/kvm_hyp.h
+++ b/arch/arm64/include/asm/kvm_hyp.h
@@ -95,7 +95,7 @@ void __sve_restore_state(void *sve_pffr, u32 *fpsr);
#ifndef __KVM_NVHE_HYPERVISOR__
void activate_traps_vhe_load(struct kvm_vcpu *vcpu);
-void deactivate_traps_vhe_put(void);
+void deactivate_traps_vhe_put(struct kvm_vcpu *vcpu);
#endif
u64 __guest_enter(struct kvm_vcpu *vcpu);
diff --git a/arch/arm64/kvm/hyp/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h
index e4a2f295a394..a0e78a6027be 100644
--- a/arch/arm64/kvm/hyp/include/hyp/switch.h
+++ b/arch/arm64/kvm/hyp/include/hyp/switch.h
@@ -92,11 +92,15 @@ static inline void __activate_traps_common(struct kvm_vcpu *vcpu)
write_sysreg(0, pmselr_el0);
write_sysreg(ARMV8_PMU_USERENR_MASK, pmuserenr_el0);
}
+
+ vcpu->arch.mdcr_el2_host = read_sysreg(mdcr_el2);
write_sysreg(vcpu->arch.mdcr_el2, mdcr_el2);
}
-static inline void __deactivate_traps_common(void)
+static inline void __deactivate_traps_common(struct kvm_vcpu *vcpu)
{
+ write_sysreg(vcpu->arch.mdcr_el2_host, mdcr_el2);
+
write_sysreg(0, hstr_el2);
if (kvm_arm_support_pmu_v3())
write_sysreg(0, pmuserenr_el0);
diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c
index f7af9688c1f7..1778593a08a9 100644
--- a/arch/arm64/kvm/hyp/nvhe/switch.c
+++ b/arch/arm64/kvm/hyp/nvhe/switch.c
@@ -69,12 +69,10 @@ static void __activate_traps(struct kvm_vcpu *vcpu)
static void __deactivate_traps(struct kvm_vcpu *vcpu)
{
extern char __kvm_hyp_host_vector[];
- u64 mdcr_el2, cptr;
+ u64 cptr;
___deactivate_traps(vcpu);
- mdcr_el2 = read_sysreg(mdcr_el2);
-
if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) {
u64 val;
@@ -92,13 +90,8 @@ static void __deactivate_traps(struct kvm_vcpu *vcpu)
isb();
}
- __deactivate_traps_common();
-
- mdcr_el2 &= MDCR_EL2_HPMN_MASK;
- mdcr_el2 |= MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT;
- mdcr_el2 |= MDCR_EL2_E2TB_MASK << MDCR_EL2_E2TB_SHIFT;
+ __deactivate_traps_common(vcpu);
- write_sysreg(mdcr_el2, mdcr_el2);
write_sysreg(this_cpu_ptr(&kvm_init_params)->hcr_el2, hcr_el2);
cptr = CPTR_EL2_DEFAULT;
diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c
index b3229924d243..0d0c9550fb08 100644
--- a/arch/arm64/kvm/hyp/vhe/switch.c
+++ b/arch/arm64/kvm/hyp/vhe/switch.c
@@ -91,17 +91,9 @@ void activate_traps_vhe_load(struct kvm_vcpu *vcpu)
__activate_traps_common(vcpu);
}
-void deactivate_traps_vhe_put(void)
+void deactivate_traps_vhe_put(struct kvm_vcpu *vcpu)
{
- u64 mdcr_el2 = read_sysreg(mdcr_el2);
-
- mdcr_el2 &= MDCR_EL2_HPMN_MASK |
- MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT |
- MDCR_EL2_TPMS;
-
- write_sysreg(mdcr_el2, mdcr_el2);
-
- __deactivate_traps_common();
+ __deactivate_traps_common(vcpu);
}
/* Switch to the guest for VHE systems running in EL2 */
diff --git a/arch/arm64/kvm/hyp/vhe/sysreg-sr.c b/arch/arm64/kvm/hyp/vhe/sysreg-sr.c
index 2a0b8c88d74f..007a12dd4351 100644
--- a/arch/arm64/kvm/hyp/vhe/sysreg-sr.c
+++ b/arch/arm64/kvm/hyp/vhe/sysreg-sr.c
@@ -101,7 +101,7 @@ void kvm_vcpu_put_sysregs_vhe(struct kvm_vcpu *vcpu)
struct kvm_cpu_context *host_ctxt;
host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
- deactivate_traps_vhe_put();
+ deactivate_traps_vhe_put(vcpu);
__sysreg_save_el1_state(guest_ctxt);
__sysreg_save_user_state(guest_ctxt);
--
2.32.0.402.g57bb445576-goog
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next prev parent reply other threads:[~2021-07-19 16:11 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-19 16:03 [PATCH v3 00/15] KVM: arm64: Fixed features for protected VMs Fuad Tabba
2021-07-19 16:03 ` [PATCH v3 01/15] KVM: arm64: placeholder to check if VM is protected Fuad Tabba
2021-08-12 8:58 ` Will Deacon
2021-08-12 9:22 ` Fuad Tabba
2021-07-19 16:03 ` [PATCH v3 02/15] KVM: arm64: Remove trailing whitespace in comment Fuad Tabba
2021-08-12 8:59 ` Will Deacon
2021-07-19 16:03 ` [PATCH v3 03/15] KVM: arm64: MDCR_EL2 is a 64-bit register Fuad Tabba
2021-07-19 16:03 ` [PATCH v3 04/15] KVM: arm64: Fix names of config register fields Fuad Tabba
2021-07-19 16:03 ` [PATCH v3 05/15] KVM: arm64: Refactor sys_regs.h,c for nVHE reuse Fuad Tabba
2021-07-20 13:38 ` [PATCH v3 05/15] KVM: arm64: Refactor sys_regs.h, c " Andrew Jones
2021-07-20 14:03 ` Fuad Tabba
2021-08-12 8:59 ` Will Deacon
2021-07-19 16:03 ` Fuad Tabba [this message]
2021-07-20 14:52 ` [PATCH v3 06/15] KVM: arm64: Restore mdcr_el2 from vcpu Andrew Jones
2021-07-21 7:37 ` Fuad Tabba
2021-08-12 8:46 ` Will Deacon
2021-08-12 9:28 ` Fuad Tabba
2021-08-12 9:49 ` Will Deacon
2021-07-19 16:03 ` [PATCH v3 07/15] KVM: arm64: Track value of cptr_el2 in struct kvm_vcpu_arch Fuad Tabba
2021-08-12 8:59 ` Will Deacon
2021-07-19 16:03 ` [PATCH v3 08/15] KVM: arm64: Add feature register flag definitions Fuad Tabba
2021-08-12 8:59 ` Will Deacon
2021-08-12 9:21 ` Fuad Tabba
2021-07-19 16:03 ` [PATCH v3 09/15] KVM: arm64: Add config register bit definitions Fuad Tabba
2021-08-12 8:59 ` Will Deacon
2021-07-19 16:03 ` [PATCH v3 10/15] KVM: arm64: Guest exit handlers for nVHE hyp Fuad Tabba
2021-08-03 15:32 ` Will Deacon
2021-07-19 16:03 ` [PATCH v3 11/15] KVM: arm64: Add trap handlers for protected VMs Fuad Tabba
2021-08-12 9:45 ` Will Deacon
2021-08-16 14:39 ` Fuad Tabba
2021-07-19 16:03 ` [PATCH v3 12/15] KVM: arm64: Move sanitized copies of CPU features Fuad Tabba
2021-08-12 9:46 ` Will Deacon
2021-07-19 16:03 ` [PATCH v3 13/15] KVM: arm64: Trap access to pVM restricted features Fuad Tabba
2021-08-12 9:53 ` Will Deacon
2021-07-19 16:03 ` [PATCH v3 14/15] KVM: arm64: Handle protected guests at 32 bits Fuad Tabba
2021-07-19 19:43 ` Oliver Upton
2021-07-21 8:39 ` Fuad Tabba
2021-08-12 9:57 ` Will Deacon
2021-08-12 13:08 ` Fuad Tabba
2021-07-19 16:03 ` [PATCH v3 15/15] KVM: arm64: Restrict protected VM capabilities Fuad Tabba
2021-08-12 9:59 ` Will Deacon
2021-08-16 14:40 ` Fuad Tabba
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