[PATCH RFC 36/37] KVM: arm64: Disable MTE is tag storage is enabled
From: Alexandru Elisei <hidden>
Date: 2023-08-23 13:19:22
Also in:
kvmarm, linux-arch, linux-arm-kernel, linux-fsdevel, linux-mm, lkml
Subsystem:
arm64 port (aarch64 architecture), kernel virtual machine for arm64 (kvm/arm64), the rest · Maintainers:
Catalin Marinas, Will Deacon, Marc Zyngier, Oliver Upton, Linus Torvalds
KVM allows MTE enabled VMs to be created when the backing memory is does not have MTE enabled. Without changes to how KVM allocates memory for a VM, it is impossible to discern when the corresponding tag storage needs to be reserved. For now, disable MTE in KVM if tag storage is enabled. Signed-off-by: Alexandru Elisei <redacted> --- arch/arm64/kvm/arm.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 72dc53a75d1c..1f39c2d5223d 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c@@ -38,6 +38,7 @@ #include <asm/kvm_mmu.h> #include <asm/kvm_pkvm.h> #include <asm/kvm_emulate.h> +#include <asm/memory_metadata.h> #include <asm/sections.h> #include <kvm/arm_hypercalls.h>
@@ -85,7 +86,8 @@ int kvm_vm_ioctl_enable_cap(struct kvm *kvm, break; case KVM_CAP_ARM_MTE: mutex_lock(&kvm->lock); - if (!system_supports_mte() || kvm->created_vcpus) { + if (!system_supports_mte() || metadata_storage_enabled() || + kvm->created_vcpus) { r = -EINVAL; } else { r = 0;
@@ -277,7 +279,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) r = 1; break; case KVM_CAP_ARM_MTE: - r = system_supports_mte(); + r = system_supports_mte() && !metadata_storage_enabled(); break; case KVM_CAP_STEAL_TIME: r = kvm_arm_pvtime_supported();
--
2.41.0