Commit a655276a authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
Browse files

KVM: SEV: Fall back to vmalloc for SEV-ES scratch area if necessary 



Use kvzalloc() to allocate KVM's buffer for SEV-ES's GHCB scratch area so
that KVM falls back to __vmalloc() if physically contiguous memory isn't
available.  The buffer is purely a KVM software construct, i.e. there's
no need for it to be physically contiguous.

Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
Message-Id: <20211109222350.2266045-3-seanjc@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 75236f5f

arch/x86/kvm/svm/sev.c

+4 −4
Original line number Diff line number Diff line
@@ -2260,7 +2260,7 @@ void sev_free_vcpu(struct kvm_vcpu *vcpu) 
	__free_page(virt_to_page(svm->sev_es.vmsa));



	if (svm->sev_es.ghcb_sa_free)

		kfree(svm->sev_es.ghcb_sa);

		kvfree(svm->sev_es.ghcb_sa);

}



static void dump_ghcb(struct vcpu_svm *svm)
@@ -2493,7 +2493,7 @@ void sev_es_unmap_ghcb(struct vcpu_svm *svm) 
			svm->sev_es.ghcb_sa_sync = false;

		}



		kfree(svm->sev_es.ghcb_sa);

		kvfree(svm->sev_es.ghcb_sa);

		svm->sev_es.ghcb_sa = NULL;

		svm->sev_es.ghcb_sa_free = false;

	}
@@ -2581,7 +2581,7 @@ static int setup_vmgexit_scratch(struct vcpu_svm *svm, bool sync, u64 len) 
			       len, GHCB_SCRATCH_AREA_LIMIT);

			return -EINVAL;

		}

		scratch_va = kzalloc(len, GFP_KERNEL_ACCOUNT);

		scratch_va = kvzalloc(len, GFP_KERNEL_ACCOUNT);

		if (!scratch_va)

			return -ENOMEM;
@@ -2589,7 +2589,7 @@ static int setup_vmgexit_scratch(struct vcpu_svm *svm, bool sync, u64 len) 
			/* Unable to copy scratch area from guest */

			pr_err("vmgexit: kvm_read_guest for scratch area failed\n");



			kfree(scratch_va);

			kvfree(scratch_va);

			return -EFAULT;

		}