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From: Will Deacon <will@kernel.org>
To: kvmarm@lists.cs.columbia.edu
Cc: catalin.marinas@arm.com, kernel-team@android.com,
	Will Deacon <will@kernel.org>, Marc Zyngier <maz@kernel.org>
Subject: [PATCH v2 2/9] KVM: arm64: Tidy up kvm_map_vector()
Date: Mon,  9 Nov 2020 21:47:19 +0000	[thread overview]
Message-ID: <20201109214726.15276-3-will@kernel.org> (raw)
In-Reply-To: <20201109214726.15276-1-will@kernel.org>

The bulk of the work in kvm_map_vector() is conditional on the
ARM64_HARDEN_EL2_VECTORS capability, so return early if that is not set
and make the code a bit easier to read.

Cc: Marc Zyngier <maz@kernel.org>
Cc: Quentin Perret <qperret@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
---
 arch/arm64/kvm/arm.c | 28 ++++++++++++++--------------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index b43b637ded14..476bc613d0e6 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -1297,6 +1297,8 @@ static unsigned long nvhe_percpu_order(void)
 
 static int kvm_map_vectors(void)
 {
+	int slot;
+
 	/*
 	 * SV2  = ARM64_SPECTRE_V2
 	 * HEL2 = ARM64_HARDEN_EL2_VECTORS
@@ -1306,22 +1308,20 @@ static int kvm_map_vectors(void)
 	 * !SV2 +  HEL2 -> allocate one vector slot and use exec mapping
 	 *  SV2 +  HEL2 -> use hardened vectors and use exec mapping
 	 */
-	if (cpus_have_const_cap(ARM64_HARDEN_EL2_VECTORS)) {
-		phys_addr_t vect_pa = __pa_symbol(__bp_harden_hyp_vecs);
-		unsigned long size = __BP_HARDEN_HYP_VECS_SZ;
+	if (!cpus_have_const_cap(ARM64_HARDEN_EL2_VECTORS))
+		return 0;
 
-		/*
-		 * Always allocate a spare vector slot, as we don't
-		 * know yet which CPUs have a BP hardening slot that
-		 * we can reuse.
-		 */
-		__kvm_harden_el2_vector_slot = atomic_inc_return(&arm64_el2_vector_last_slot);
-		BUG_ON(__kvm_harden_el2_vector_slot >= BP_HARDEN_EL2_SLOTS);
-		return create_hyp_exec_mappings(vect_pa, size,
-						&__kvm_bp_vect_base);
-	}
+	/*
+	 * Always allocate a spare vector slot, as we don't know yet which CPUs
+	 * have a BP hardening slot that we can reuse.
+	 */
+	slot = atomic_inc_return(&arm64_el2_vector_last_slot);
+	BUG_ON(slot >= BP_HARDEN_EL2_SLOTS);
+	__kvm_harden_el2_vector_slot = slot;
 
-	return 0;
+	return create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs),
+					__BP_HARDEN_HYP_VECS_SZ,
+					&__kvm_bp_vect_base);
 }
 
 static void cpu_init_hyp_mode(void)
-- 
2.29.2.222.g5d2a92d10f8-goog

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  parent reply	other threads:[~2020-11-09 21:47 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-11-09 21:47 [PATCH v2 0/9] Rework hyp vector handling Will Deacon
2020-11-09 21:47 ` [PATCH v2 1/9] KVM: arm64: Remove redundant Spectre-v2 code from kvm_map_vector() Will Deacon
2020-11-09 21:47 ` Will Deacon [this message]
2020-11-09 21:47 ` [PATCH v2 3/9] KVM: arm64: Move kvm_get_hyp_vector() out of header file Will Deacon
2020-11-09 21:47 ` [PATCH v2 4/9] KVM: arm64: Make BP hardening globals static instead Will Deacon
2020-11-09 21:47 ` [PATCH v2 5/9] KVM: arm64: Move BP hardening helpers into spectre.h Will Deacon
2020-11-09 21:47 ` [PATCH v2 6/9] KVM: arm64: Re-jig logic when patching hardened hyp vectors Will Deacon
2020-11-09 21:47 ` [PATCH v2 7/9] KVM: arm64: Allocate hyp vectors statically Will Deacon
2020-11-12 11:07   ` Marc Zyngier
2020-11-12 11:27     ` Will Deacon
2020-11-12 12:05   ` Marc Zyngier
2020-11-12 12:24     ` Will Deacon
2020-11-09 21:47 ` [PATCH v2 8/9] arm64: spectre: Rename ARM64_HARDEN_EL2_VECTORS to ARM64_SPECTRE_V3A Will Deacon
2020-11-09 21:47 ` [PATCH v2 9/9] arm64: spectre: Consolidate spectre-v3a detection Will Deacon

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