Move allocation of VMX and SVM vcpus to common x86. Although the struct being allocated is technically a VMX/SVM struct, it can be interpreted directly as a 'struct kvm_vcpu' because of the pre-existing requirement that 'struct kvm_vcpu' be located at offset zero of the arch/vendor vcpu struct. Remove the message from the build-time assertions regarding placement of the struct, as compatibility with the arch usercopy region is no longer the sole dependent on 'struct kvm_vcpu' being at offset zero. Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx> --- arch/x86/include/asm/kvm_host.h | 2 +- arch/x86/kvm/svm.c | 28 +++++++++------------------- arch/x86/kvm/vmx/vmx.c | 24 ++++++++---------------- arch/x86/kvm/x86.c | 16 ++++++++++++---- 4 files changed, 30 insertions(+), 40 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 5d8056ff7390..77581eeb02e3 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1014,7 +1014,7 @@ struct kvm_x86_ops { void (*vm_destroy)(struct kvm *kvm); /* Create, but do not attach this VCPU */ - struct kvm_vcpu *(*vcpu_create)(struct kvm *kvm, unsigned id); + int (*vcpu_create)(struct kvm *kvm, struct kvm_vcpu *vcpu, unsigned id); void (*vcpu_free)(struct kvm_vcpu *vcpu); void (*vcpu_reset)(struct kvm_vcpu *vcpu, bool init_event); diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 2f66c52e1b5d..bbc5dac9d400 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -2138,9 +2138,9 @@ static int avic_init_vcpu(struct vcpu_svm *svm) return ret; } -static struct kvm_vcpu *svm_create_vcpu(struct kvm *kvm, unsigned int id) +static int svm_create_vcpu(struct kvm *kvm, struct kvm_vcpu *vcpu, + unsigned int id) { - struct kvm_vcpu *vcpu; struct vcpu_svm *svm; struct page *page; struct page *msrpm_pages; @@ -2148,22 +2148,15 @@ static struct kvm_vcpu *svm_create_vcpu(struct kvm *kvm, unsigned int id) struct page *nested_msrpm_pages; int err; - BUILD_BUG_ON_MSG(offsetof(struct vcpu_svm, vcpu) != 0, - "struct kvm_vcpu must be at offset 0 for arch usercopy region"); - - svm = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL_ACCOUNT); - if (!svm) { - err = -ENOMEM; - goto out; - } - vcpu = &svm->vcpu; + BUILD_BUG_ON(offsetof(struct vcpu_svm, vcpu) != 0); + svm = to_svm(vcpu); vcpu->arch.user_fpu = kmem_cache_zalloc(x86_fpu_cache, GFP_KERNEL_ACCOUNT); if (!vcpu->arch.user_fpu) { printk(KERN_ERR "kvm: failed to allocate kvm userspace's fpu\n"); err = -ENOMEM; - goto free_partial_svm; + goto out; } vcpu->arch.guest_fpu = kmem_cache_zalloc(x86_fpu_cache, @@ -2176,7 +2169,7 @@ static struct kvm_vcpu *svm_create_vcpu(struct kvm *kvm, unsigned int id) err = kvm_vcpu_init(vcpu, kvm, id); if (err) - goto free_svm; + goto free_guest_fpu; err = -ENOMEM; page = alloc_page(GFP_KERNEL_ACCOUNT); @@ -2220,7 +2213,7 @@ static struct kvm_vcpu *svm_create_vcpu(struct kvm *kvm, unsigned int id) svm_init_osvw(vcpu); - return vcpu; + return 0; free_page4: __free_page(hsave_page); @@ -2232,14 +2225,12 @@ static struct kvm_vcpu *svm_create_vcpu(struct kvm *kvm, unsigned int id) __free_page(page); uninit: kvm_vcpu_uninit(vcpu); -free_svm: +free_guest_fpu: kmem_cache_free(x86_fpu_cache, vcpu->arch.guest_fpu); free_user_fpu: kmem_cache_free(x86_fpu_cache, vcpu->arch.user_fpu); -free_partial_svm: - kmem_cache_free(kvm_vcpu_cache, svm); out: - return ERR_PTR(err); + return err; } static void svm_clear_current_vmcb(struct vmcb *vmcb) @@ -2268,7 +2259,6 @@ static void svm_free_vcpu(struct kvm_vcpu *vcpu) kvm_vcpu_uninit(vcpu); kmem_cache_free(x86_fpu_cache, vcpu->arch.user_fpu); kmem_cache_free(x86_fpu_cache, vcpu->arch.guest_fpu); - kmem_cache_free(kvm_vcpu_cache, svm); } static void svm_vcpu_load(struct kvm_vcpu *vcpu, int cpu) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 70b8d15eb2c5..832d8e38acd4 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -6693,31 +6693,24 @@ static void vmx_free_vcpu(struct kvm_vcpu *vcpu) kvm_vcpu_uninit(vcpu); kmem_cache_free(x86_fpu_cache, vcpu->arch.user_fpu); kmem_cache_free(x86_fpu_cache, vcpu->arch.guest_fpu); - kmem_cache_free(kvm_vcpu_cache, vmx); } -static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id) +static int vmx_create_vcpu(struct kvm *kvm, struct kvm_vcpu *vcpu, + unsigned int id) { - struct kvm_vcpu *vcpu; struct vcpu_vmx *vmx; unsigned long *msr_bitmap; int cpu, err; - BUILD_BUG_ON_MSG(offsetof(struct vcpu_vmx, vcpu) != 0, - "struct kvm_vcpu must be at offset 0 for arch usercopy region"); - - vmx = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL_ACCOUNT); - if (!vmx) - return ERR_PTR(-ENOMEM); - - vcpu = &vmx->vcpu; + BUILD_BUG_ON(offsetof(struct vcpu_vmx, vcpu) != 0); + vmx = to_vmx(vcpu); vcpu->arch.user_fpu = kmem_cache_zalloc(x86_fpu_cache, GFP_KERNEL_ACCOUNT); if (!vcpu->arch.user_fpu) { printk(KERN_ERR "kvm: failed to allocate kvm userspace's fpu\n"); err = -ENOMEM; - goto free_partial_vcpu; + goto out; } vcpu->arch.guest_fpu = kmem_cache_zalloc(x86_fpu_cache, @@ -6815,7 +6808,7 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id) vmx->ept_pointer = INVALID_PAGE; - return vcpu; + return 0; free_vmcs: free_loaded_vmcs(vmx->loaded_vmcs); @@ -6830,9 +6823,8 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id) kmem_cache_free(x86_fpu_cache, vcpu->arch.guest_fpu); free_user_fpu: kmem_cache_free(x86_fpu_cache, vcpu->arch.user_fpu); -free_partial_vcpu: - kmem_cache_free(kvm_vcpu_cache, vmx); - return ERR_PTR(err); +out: + return err; } #define L1TF_MSG_SMT "L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.\n" diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index c9a291693279..45b296a9fdbb 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -9012,26 +9012,34 @@ static void fx_init(struct kvm_vcpu *vcpu) void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu) { - void *wbinvd_dirty_mask = vcpu->arch.wbinvd_dirty_mask; - kvmclock_reset(vcpu); kvm_x86_ops->vcpu_free(vcpu); - free_cpumask_var(wbinvd_dirty_mask); + + free_cpumask_var(vcpu->arch.wbinvd_dirty_mask); + kmem_cache_free(kvm_vcpu_cache, vcpu); } struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id) { struct kvm_vcpu *vcpu; + int r; if (kvm_check_tsc_unstable() && atomic_read(&kvm->online_vcpus) != 0) printk_once(KERN_WARNING "kvm: SMP vm created on host with unstable TSC; " "guest TSC will not be reliable\n"); - vcpu = kvm_x86_ops->vcpu_create(kvm, id); + vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL_ACCOUNT); + if (!vcpu) + return ERR_PTR(-ENOMEM); + r = kvm_x86_ops->vcpu_create(kvm, vcpu, id); + if (r) { + kmem_cache_free(kvm_vcpu_cache, vcpu); + return ERR_PTR(r); + } return vcpu; } -- 2.22.0