From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brijesh Singh Subject: [PATCH v10 12/28] sev/i386: register the guest memory range which may contain encrypted data Date: Wed, 28 Feb 2018 15:10:12 -0600 Message-ID: <20180228211028.83970-13-brijesh.singh@amd.com> References: <20180228211028.83970-1-brijesh.singh@amd.com> Mime-Version: 1.0 Content-Type: text/plain Cc: Peter Maydell , Brijesh Singh , kvm@vger.kernel.org, "Michael S. Tsirkin" , Stefan Hajnoczi , Alexander Graf , "Edgar E. Iglesias" , Markus Armbruster , Bruce Rogers , Christian Borntraeger , Marcel Apfelbaum , Borislav Petkov , Thomas Lendacky , Eduardo Habkost , Richard Henderson , "Dr. David Alan Gilbert" , Alistair Francis , Cornelia Huck , Richard Henderson , Peter Crosthwaite , Paolo Bonzini To: qemu-devel@nongnu.org Return-path: In-Reply-To: <20180228211028.83970-1-brijesh.singh@amd.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+gceq-qemu-devel2=m.gmane.org@nongnu.org Sender: "Qemu-devel" List-Id: kvm.vger.kernel.org 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 Cc: Richard Henderson Cc: Eduardo Habkost Signed-off-by: Brijesh Singh --- target/i386/sev.c | 41 +++++++++++++++++++++++++++++++++++++++++ target/i386/trace-events | 2 ++ 2 files changed, 43 insertions(+) diff --git a/target/i386/sev.c b/target/i386/sev.c index 80569f4bcf49..8ee6159b2bfc 100644 --- a/target/i386/sev.c +++ b/target/i386/sev.c @@ -100,6 +100,45 @@ fw_error_to_str(int code) return sev_fw_errlist[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) { @@ -434,6 +473,8 @@ sev_guest_init(const char *id) goto err; } + ram_block_notifier_add(&sev_ram_notifier); + return s; err: g_free(sev_state); diff --git a/target/i386/trace-events b/target/i386/trace-events index 797b716751b7..ffa3d2250425 100644 --- a/target/i386/trace-events +++ b/target/i386/trace-events @@ -8,3 +8,5 @@ kvm_x86_update_msi_routes(int num) "Updated %d MSI routes" # target/i386/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" -- 2.14.3 From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53224) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1er90I-0001JQ-Hv for qemu-devel@nongnu.org; Wed, 28 Feb 2018 16:11:12 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1er90E-0005l0-MF for qemu-devel@nongnu.org; Wed, 28 Feb 2018 16:11:10 -0500 Received: from mail-sn1nam02on0070.outbound.protection.outlook.com ([104.47.36.70]:44829 helo=NAM02-SN1-obe.outbound.protection.outlook.com) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1er90E-0005jA-Df for qemu-devel@nongnu.org; Wed, 28 Feb 2018 16:11:06 -0500 From: Brijesh Singh Date: Wed, 28 Feb 2018 15:10:12 -0600 Message-Id: <20180228211028.83970-13-brijesh.singh@amd.com> In-Reply-To: <20180228211028.83970-1-brijesh.singh@amd.com> References: <20180228211028.83970-1-brijesh.singh@amd.com> MIME-Version: 1.0 Content-Type: text/plain Subject: [Qemu-devel] [PATCH v10 12/28] sev/i386: register the guest memory range which may contain encrypted data List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Alistair Francis , Christian Borntraeger , Cornelia Huck , "Daniel P . Berrange" , "Dr. David Alan Gilbert" , "Michael S. Tsirkin" , "Edgar E. Iglesias" , Eduardo Habkost , Eric Blake , kvm@vger.kernel.org, Marcel Apfelbaum , Markus Armbruster , Paolo Bonzini , Peter Crosthwaite , Peter Maydell , Richard Henderson , Stefan Hajnoczi , Thomas Lendacky , Borislav Petkov , Alexander Graf , Bruce Rogers , Brijesh Singh , Richard Henderson 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 Cc: Richard Henderson Cc: Eduardo Habkost Signed-off-by: Brijesh Singh --- target/i386/sev.c | 41 +++++++++++++++++++++++++++++++++++++++++ target/i386/trace-events | 2 ++ 2 files changed, 43 insertions(+) diff --git a/target/i386/sev.c b/target/i386/sev.c index 80569f4bcf49..8ee6159b2bfc 100644 --- a/target/i386/sev.c +++ b/target/i386/sev.c @@ -100,6 +100,45 @@ fw_error_to_str(int code) return sev_fw_errlist[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) { @@ -434,6 +473,8 @@ sev_guest_init(const char *id) goto err; } + ram_block_notifier_add(&sev_ram_notifier); + return s; err: g_free(sev_state); diff --git a/target/i386/trace-events b/target/i386/trace-events index 797b716751b7..ffa3d2250425 100644 --- a/target/i386/trace-events +++ b/target/i386/trace-events @@ -8,3 +8,5 @@ kvm_x86_update_msi_routes(int num) "Updated %d MSI routes" # target/i386/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" -- 2.14.3