From 10c02aad111df02088d1a81792a709f6a7eca6cc Mon Sep 17 00:00:00 2001 From: Sebastian Ene Date: Wed, 24 Jan 2024 09:10:28 +0000 Subject: KVM: arm64: Fix circular locking dependency The rule inside kvm enforces that the vcpu->mutex is taken *inside* kvm->lock. The rule is violated by the pkvm_create_hyp_vm() which acquires the kvm->lock while already holding the vcpu->mutex lock from kvm_vcpu_ioctl(). Avoid the circular locking dependency altogether by protecting the hyp vm handle with the config_lock, much like we already do for other forms of VM-scoped data. Signed-off-by: Sebastian Ene Cc: stable@vger.kernel.org Reviewed-by: Oliver Upton Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20240124091027.1477174-2-sebastianene@google.com --- arch/arm64/kvm/pkvm.c | 27 +++++++++++++++++---------- 1 file changed, 17 insertions(+), 10 deletions(-) diff --git a/arch/arm64/kvm/pkvm.c b/arch/arm64/kvm/pkvm.c index 8350fb8fee0b..b7be96a53597 100644 --- a/arch/arm64/kvm/pkvm.c +++ b/arch/arm64/kvm/pkvm.c @@ -101,6 +101,17 @@ void __init kvm_hyp_reserve(void) hyp_mem_base); } +static void __pkvm_destroy_hyp_vm(struct kvm *host_kvm) +{ + if (host_kvm->arch.pkvm.handle) { + WARN_ON(kvm_call_hyp_nvhe(__pkvm_teardown_vm, + host_kvm->arch.pkvm.handle)); + } + + host_kvm->arch.pkvm.handle = 0; + free_hyp_memcache(&host_kvm->arch.pkvm.teardown_mc); +} + /* * Allocates and donates memory for hypervisor VM structs at EL2. * @@ -181,7 +192,7 @@ static int __pkvm_create_hyp_vm(struct kvm *host_kvm) return 0; destroy_vm: - pkvm_destroy_hyp_vm(host_kvm); + __pkvm_destroy_hyp_vm(host_kvm); return ret; free_vm: free_pages_exact(hyp_vm, hyp_vm_sz); @@ -194,23 +205,19 @@ int pkvm_create_hyp_vm(struct kvm *host_kvm) { int ret = 0; - mutex_lock(&host_kvm->lock); + mutex_lock(&host_kvm->arch.config_lock); if (!host_kvm->arch.pkvm.handle) ret = __pkvm_create_hyp_vm(host_kvm); - mutex_unlock(&host_kvm->lock); + mutex_unlock(&host_kvm->arch.config_lock); return ret; } void pkvm_destroy_hyp_vm(struct kvm *host_kvm) { - if (host_kvm->arch.pkvm.handle) { - WARN_ON(kvm_call_hyp_nvhe(__pkvm_teardown_vm, - host_kvm->arch.pkvm.handle)); - } - - host_kvm->arch.pkvm.handle = 0; - free_hyp_memcache(&host_kvm->arch.pkvm.teardown_mc); + mutex_lock(&host_kvm->arch.config_lock); + __pkvm_destroy_hyp_vm(host_kvm); + mutex_unlock(&host_kvm->arch.config_lock); } int pkvm_init_host_vm(struct kvm *host_kvm) -- cgit v1.2.3 From 42dfa94d802a48c871e2017cbf86153270c86632 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 4 Feb 2024 16:43:05 +0900 Subject: KVM: arm64: Do not source virt/lib/Kconfig twice For ARCH=arm64, virt/lib/Kconfig is sourced twice, from arch/arm64/kvm/Kconfig and from drivers/vfio/Kconfig. There is no good reason to parse virt/lib/Kconfig twice. Commit 2412405b3141 ("KVM: arm/arm64: register irq bypass consumer on ARM/ARM64") should not have added this 'source' directive. Signed-off-by: Masahiro Yamada Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20240204074305.31492-1-masahiroy@kernel.org --- arch/arm64/kvm/Kconfig | 1 - 1 file changed, 1 deletion(-) diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig index 6c3c8ca73e7f..27ca89b628a0 100644 --- a/arch/arm64/kvm/Kconfig +++ b/arch/arm64/kvm/Kconfig @@ -3,7 +3,6 @@ # KVM configuration # -source "virt/lib/Kconfig" source "virt/kvm/Kconfig" menuconfig VIRTUALIZATION -- cgit v1.2.3