[PATCH 09/17] KVM: arm64: Key use of VHE instructions in nVHE code off ARM64_KVM_HVHE

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From: Marc Zyngier <maz@kernel.org>
To: <kvmarm@lists.cs.columbia.edu>, <kvmarm@lists.linux.dev>,
	kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org
Cc: Will Deacon <will@kernel.org>
Subject: [PATCH 09/17] KVM: arm64: Key use of VHE instructions in nVHE code off ARM64_KVM_HVHE
Date: Thu, 20 Oct 2022 10:07:19 +0100	[thread overview]
Message-ID: <20221020090727.3669908-10-maz@kernel.org> (raw)
In-Reply-To: <20221020090727.3669908-1-maz@kernel.org>

We can now start with the fun stuff: if we enable VHE *only* for
the hypervisor, we need to generate the VHE instructions when
accessing the system registers.

For this, reporpose the alternative sequence to be keyed off
ARM64_KVM_HVHE in the nVHE hypervisor code, and only there.

Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 arch/arm64/include/asm/kvm_hyp.h | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h
index 461fc0dc4a70..e45215a62b43 100644
--- a/arch/arm64/include/asm/kvm_hyp.h
+++ b/arch/arm64/include/asm/kvm_hyp.h
@@ -33,12 +33,18 @@ DECLARE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
 
 #else // !__KVM_VHE_HYPERVISOR__
 
+#if defined(__KVM_NVHE_HYPERVISOR__)
+#define VHE_ALT_KEY	ARM64_KVM_HVHE
+#else
+#define VHE_ALT_KEY	ARM64_HAS_VIRT_HOST_EXTN
+#endif
+
 #define read_sysreg_elx(r,nvh,vh)					\
 	({								\
 		u64 reg;						\
-		asm volatile(ALTERNATIVE(__mrs_s("%0", r##nvh),	\
+		asm volatile(ALTERNATIVE(__mrs_s("%0", r##nvh),		\
 					 __mrs_s("%0", r##vh),		\
-					 ARM64_HAS_VIRT_HOST_EXTN)	\
+					 VHE_ALT_KEY)			\
 			     : "=r" (reg));				\
 		reg;							\
 	})
@@ -48,7 +54,7 @@ DECLARE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
 		u64 __val = (u64)(v);					\
 		asm volatile(ALTERNATIVE(__msr_s(r##nvh, "%x0"),	\
 					 __msr_s(r##vh, "%x0"),		\
-					 ARM64_HAS_VIRT_HOST_EXTN)	\
+					 VHE_ALT_KEY)			\
 					 : : "rZ" (__val));		\
 	} while (0)
 
-- 
2.34.1

_______________________________________________
kvmarm mailing list
kvmarm@lists.cs.columbia.edu
https://lists.cs.columbia.edu/mailman/listinfo/kvmarm

WARNING: multiple messages have this Message-ID (diff)

From: Marc Zyngier <maz@kernel.org>
To: <kvmarm@lists.cs.columbia.edu>, <kvmarm@lists.linux.dev>,
	kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org
Cc: James Morse <james.morse@arm.com>,
	Suzuki K Poulose <suzuki.poulose@arm.com>,
	Alexandru Elisei <alexandru.elisei@arm.com>,
	Oliver Upton <oliver.upton@linux.dev>,
	Quentin Perret <qperret@google.com>,
	Will Deacon <will@kernel.org>, Fuad Tabba <tabba@google.com>
Subject: [PATCH 09/17] KVM: arm64: Key use of VHE instructions in nVHE code off ARM64_KVM_HVHE
Date: Thu, 20 Oct 2022 10:07:19 +0100	[thread overview]
Message-ID: <20221020090727.3669908-10-maz@kernel.org> (raw)
Message-ID: <20221020090719.UmjZljE9ykyqo7sIZR2ckiZuzmnKA9I8tlAuPfS8aAI@z> (raw)
In-Reply-To: <20221020090727.3669908-1-maz@kernel.org>

We can now start with the fun stuff: if we enable VHE *only* for
the hypervisor, we need to generate the VHE instructions when
accessing the system registers.

For this, reporpose the alternative sequence to be keyed off
ARM64_KVM_HVHE in the nVHE hypervisor code, and only there.

Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 arch/arm64/include/asm/kvm_hyp.h | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h
index 461fc0dc4a70..e45215a62b43 100644
--- a/arch/arm64/include/asm/kvm_hyp.h
+++ b/arch/arm64/include/asm/kvm_hyp.h
@@ -33,12 +33,18 @@ DECLARE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
 
 #else // !__KVM_VHE_HYPERVISOR__
 
+#if defined(__KVM_NVHE_HYPERVISOR__)
+#define VHE_ALT_KEY	ARM64_KVM_HVHE
+#else
+#define VHE_ALT_KEY	ARM64_HAS_VIRT_HOST_EXTN
+#endif
+
 #define read_sysreg_elx(r,nvh,vh)					\
 	({								\
 		u64 reg;						\
-		asm volatile(ALTERNATIVE(__mrs_s("%0", r##nvh),	\
+		asm volatile(ALTERNATIVE(__mrs_s("%0", r##nvh),		\
 					 __mrs_s("%0", r##vh),		\
-					 ARM64_HAS_VIRT_HOST_EXTN)	\
+					 VHE_ALT_KEY)			\
 			     : "=r" (reg));				\
 		reg;							\
 	})
@@ -48,7 +54,7 @@ DECLARE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
 		u64 __val = (u64)(v);					\
 		asm volatile(ALTERNATIVE(__msr_s(r##nvh, "%x0"),	\
 					 __msr_s(r##vh, "%x0"),		\
-					 ARM64_HAS_VIRT_HOST_EXTN)	\
+					 VHE_ALT_KEY)			\
 					 : : "rZ" (__val));		\
 	} while (0)
 
-- 
2.34.1

WARNING: multiple messages have this Message-ID (diff)

From: Marc Zyngier <maz@kernel.org>
To: <kvmarm@lists.cs.columbia.edu>, <kvmarm@lists.linux.dev>,
	kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org
Cc: James Morse <james.morse@arm.com>,
	Suzuki K Poulose <suzuki.poulose@arm.com>,
	Alexandru Elisei <alexandru.elisei@arm.com>,
	Oliver Upton <oliver.upton@linux.dev>,
	Quentin Perret <qperret@google.com>,
	Will Deacon <will@kernel.org>, Fuad Tabba <tabba@google.com>
Subject: [PATCH 09/17] KVM: arm64: Key use of VHE instructions in nVHE code off ARM64_KVM_HVHE
Date: Thu, 20 Oct 2022 10:07:19 +0100	[thread overview]
Message-ID: <20221020090727.3669908-10-maz@kernel.org> (raw)
In-Reply-To: <20221020090727.3669908-1-maz@kernel.org>

We can now start with the fun stuff: if we enable VHE *only* for
the hypervisor, we need to generate the VHE instructions when
accessing the system registers.

For this, reporpose the alternative sequence to be keyed off
ARM64_KVM_HVHE in the nVHE hypervisor code, and only there.

Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 arch/arm64/include/asm/kvm_hyp.h | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h
index 461fc0dc4a70..e45215a62b43 100644
--- a/arch/arm64/include/asm/kvm_hyp.h
+++ b/arch/arm64/include/asm/kvm_hyp.h
@@ -33,12 +33,18 @@ DECLARE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
 
 #else // !__KVM_VHE_HYPERVISOR__
 
+#if defined(__KVM_NVHE_HYPERVISOR__)
+#define VHE_ALT_KEY	ARM64_KVM_HVHE
+#else
+#define VHE_ALT_KEY	ARM64_HAS_VIRT_HOST_EXTN
+#endif
+
 #define read_sysreg_elx(r,nvh,vh)					\
 	({								\
 		u64 reg;						\
-		asm volatile(ALTERNATIVE(__mrs_s("%0", r##nvh),	\
+		asm volatile(ALTERNATIVE(__mrs_s("%0", r##nvh),		\
 					 __mrs_s("%0", r##vh),		\
-					 ARM64_HAS_VIRT_HOST_EXTN)	\
+					 VHE_ALT_KEY)			\
 			     : "=r" (reg));				\
 		reg;							\
 	})
@@ -48,7 +54,7 @@ DECLARE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
 		u64 __val = (u64)(v);					\
 		asm volatile(ALTERNATIVE(__msr_s(r##nvh, "%x0"),	\
 					 __msr_s(r##vh, "%x0"),		\
-					 ARM64_HAS_VIRT_HOST_EXTN)	\
+					 VHE_ALT_KEY)			\
 					 : : "rZ" (__val));		\
 	} while (0)
 
-- 
2.34.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

next prev parent reply	other threads:[~2022-10-20  9:07 UTC|newest]

Thread overview: 56+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-10-20  9:07 [PATCH 00/17] KVM: arm64: Allow using VHE in the nVHE hypervisor Marc Zyngier
2022-10-20  9:07 ` Marc Zyngier
2022-10-20  9:07 ` Marc Zyngier
2022-10-20  9:07 ` [PATCH 01/17] arm64: Turn kaslr_feature_override into a generic SW feature override Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07 ` [PATCH 02/17] arm64: Add KVM_HVHE capability and has_hvhe() predicate Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2023-06-01  7:01   ` Oliver Upton
2023-06-01  7:01     ` Oliver Upton
2022-10-20  9:07 ` [PATCH 03/17] arm64: Don't enable VHE for the kernel if OVERRIDE_HVHE is set Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07 ` [PATCH 04/17] arm64: Prevent the use of is_kernel_in_hyp_mode() in hypervisor code Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07 ` [PATCH 05/17] arm64: Allow EL1 physical timer access when running VHE Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07 ` [PATCH 06/17] arm64: Use CPACR_EL1 format to set CPTR_EL2 when E2H is set Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07 ` [PATCH 07/17] KVM: arm64: Elide kern_hyp_va() in VHE-specific parts of the hypervisor Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07 ` [PATCH 08/17] KVM: arm64: Remove alternatives from sysreg accessors in VHE hypervisor context Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07 ` Marc Zyngier [this message]
2022-10-20  9:07   ` [PATCH 09/17] KVM: arm64: Key use of VHE instructions in nVHE code off ARM64_KVM_HVHE Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07 ` [PATCH 10/17] KVM: arm64: Force HCR_EL2.E2H when ARM64_KVM_HVHE is set Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07 ` [PATCH 11/17] KVM: arm64: Disable TTBR1_EL2 when using ARM64_KVM_HVHE Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07 ` [PATCH 12/17] KVM: arm64: Adjust EL2 stage-1 leaf AP bits when ARM64_KVM_HVHE is set Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07 ` [PATCH 13/17] KVM: arm64: Rework CPTR_EL2 programming for HVHE configuration Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07 ` [PATCH 14/17] KVM: arm64: Program the timer traps with VHE layout in hVHE mode Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07 ` [PATCH 15/17] KVM: arm64: Force HCR_E2H in guest context when ARM64_KVM_HVHE is set Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07 ` [PATCH 16/17] arm64: Allow arm64_sw.hvhe on command line Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07 ` [PATCH 17/17] KVM: arm64: Terrible timer hack for M1 with hVHE Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier
2022-10-20  9:07   ` Marc Zyngier

find likely ancestor, descendant, or conflicting patches for this message:
( dfblob:461fc0dc4a7 dfblob:e45215a62b4 dfblob:461fc0dc4a7
dfblob:e45215a62b4 dfblob:461fc0dc4a7 dfblob:e45215a62b4 )
 OR (
bs:"[PATCH 09/17] KVM: arm64: Key use of VHE instructions in nVHE code off ARM64_KVM_HVHE" )
	(help)

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