From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brijesh Singh Subject: [PATCH v6 11/23] sev: register the guest memory range which may contain encrypted data Date: Mon, 29 Jan 2018 11:41:20 -0600 Message-ID: <20180129174132.108925-12-brijesh.singh@amd.com> References: <20180129174132.108925-1-brijesh.singh@amd.com> Mime-Version: 1.0 Content-Type: text/plain Cc: kvm@vger.kernel.org, Paolo Bonzini , Tom Lendacky , Peter Maydell , Richard Henderson , "Edgar E. Iglesias" , "Dr. David Alan Gilbert" , Eduardo Habkost , Stefan Hajnoczi , Eric Blake , "Michael S. Tsirkin" , "Daniel P . Berrange" , Brijesh Singh To: qemu-devel@nongnu.org Return-path: Received: from mail-dm3nam03on0075.outbound.protection.outlook.com ([104.47.41.75]:63152 "EHLO NAM03-DM3-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751630AbeA2RmM (ORCPT ); Mon, 29 Jan 2018 12:42:12 -0500 In-Reply-To: <20180129174132.108925-1-brijesh.singh@amd.com> Sender: kvm-owner@vger.kernel.org List-ID: When SEV is enabled, the hardware encryption engine uses a tweak such that the two identical plaintext at different location will have a different ciphertexts. So swapping or moving a ciphertexts of two guest pages will not result in plaintexts being swapped. Hence relocating a physical backing pages of the SEV guest will require some additional steps in KVM driver. The KVM_MEMORY_ENCRYPT_{UN,}REG_REGION ioctl can be used to register/unregister the guest memory region which may contain the encrypted data. KVM driver will internally handle the relocating physical backing pages of registered memory regions. Cc: Paolo Bonzini Signed-off-by: Brijesh Singh --- accel/kvm/sev.c | 41 +++++++++++++++++++++++++++++++++++++++++ accel/kvm/trace-events | 2 ++ 2 files changed, 43 insertions(+) diff --git a/accel/kvm/sev.c b/accel/kvm/sev.c index be1791e510b3..5ae37caeb361 100644 --- a/accel/kvm/sev.c +++ b/accel/kvm/sev.c @@ -85,6 +85,45 @@ fw_error_to_str(int code) } static void +sev_ram_block_added(RAMBlockNotifier *n, void *host, size_t size) +{ + int r; + struct kvm_enc_region range; + + range.addr = (__u64)host; + range.size = size; + + trace_kvm_memcrypt_register_region(host, size); + r = kvm_vm_ioctl(kvm_state, KVM_MEMORY_ENCRYPT_REG_REGION, &range); + if (r) { + error_report("%s: failed to register region (%p+%#lx)", + __func__, host, size); + } +} + +static void +sev_ram_block_removed(RAMBlockNotifier *n, void *host, size_t size) +{ + int r; + struct kvm_enc_region range; + + range.addr = (__u64)host; + range.size = size; + + trace_kvm_memcrypt_unregister_region(host, size); + r = kvm_vm_ioctl(kvm_state, KVM_MEMORY_ENCRYPT_UNREG_REGION, &range); + if (r) { + error_report("%s: failed to unregister region (%p+%#lx)", + __func__, host, size); + } +} + +static struct RAMBlockNotifier sev_ram_notifier = { + .ram_block_added = sev_ram_block_added, + .ram_block_removed = sev_ram_block_removed, +}; + +static void qsev_guest_finalize(Object *obj) { } @@ -288,6 +327,8 @@ sev_guest_init(const char *id) goto err; } + ram_block_notifier_add(&sev_ram_notifier); + return s; err: g_free(s); diff --git a/accel/kvm/trace-events b/accel/kvm/trace-events index ea487e5a5913..364c84bd7a73 100644 --- a/accel/kvm/trace-events +++ b/accel/kvm/trace-events @@ -15,3 +15,5 @@ kvm_irqchip_release_virq(int virq) "virq %d" # sev.c kvm_sev_init(void) "" +kvm_memcrypt_register_region(void *addr, size_t len) "addr %p len 0x%lu" +kvm_memcrypt_unregister_region(void *addr, size_t len) "addr %p len 0x%lu" -- 2.9.5