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* [PATCH v2 1/3] doc: Fix some mistakes in the SEV documentation
@ 2021-04-23 20:08 Tom Lendacky
  2021-04-23 20:08 ` [PATCH v2 2/3] docs: Add SEV-ES documentation to amd-memory-encryption.txt Tom Lendacky
                   ` (4 more replies)
  0 siblings, 5 replies; 10+ messages in thread
From: Tom Lendacky @ 2021-04-23 20:08 UTC (permalink / raw)
  To: qemu-devel
  Cc: Pavel Hrdina, Daniel P . Berrange, Eduardo Habkost,
	Michal Privoznik, Dr. David Alan Gilbert, Brijesh Singh,
	Paolo Bonzini, Laszlo Ersek

From: Tom Lendacky <thomas.lendacky@amd.com>

Fix some spelling and grammar mistakes in the amd-memory-encryption.txt
file. No new information added.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 docs/amd-memory-encryption.txt | 59 +++++++++++++++++-----------------
 1 file changed, 29 insertions(+), 30 deletions(-)

diff --git a/docs/amd-memory-encryption.txt b/docs/amd-memory-encryption.txt
index 145896aec7..ed85159ea7 100644
--- a/docs/amd-memory-encryption.txt
+++ b/docs/amd-memory-encryption.txt
@@ -1,38 +1,38 @@
 Secure Encrypted Virtualization (SEV) is a feature found on AMD processors.
 
 SEV is an extension to the AMD-V architecture which supports running encrypted
-virtual machine (VMs) under the control of KVM. Encrypted VMs have their pages
+virtual machines (VMs) under the control of KVM. Encrypted VMs have their pages
 (code and data) secured such that only the guest itself has access to the
 unencrypted version. Each encrypted VM is associated with a unique encryption
-key; if its data is accessed to a different entity using a different key the
+key; if its data is accessed by a different entity using a different key the
 encrypted guests data will be incorrectly decrypted, leading to unintelligible
 data.
 
-The key management of this feature is handled by separate processor known as
-AMD secure processor (AMD-SP) which is present in AMD SOCs. Firmware running
-inside the AMD-SP provide commands to support common VM lifecycle. This
+Key management for this feature is handled by a separate processor known as the
+AMD secure processor (AMD-SP), which is present in AMD SOCs. Firmware running
+inside the AMD-SP provides commands to support a common VM lifecycle. This
 includes commands for launching, snapshotting, migrating and debugging the
-encrypted guest. Those SEV command can be issued via KVM_MEMORY_ENCRYPT_OP
+encrypted guest. These SEV commands can be issued via KVM_MEMORY_ENCRYPT_OP
 ioctls.
 
 Launching
 ---------
-Boot images (such as bios) must be encrypted before guest can be booted.
-MEMORY_ENCRYPT_OP ioctl provides commands to encrypt the images :LAUNCH_START,
+Boot images (such as bios) must be encrypted before a guest can be booted. The
+MEMORY_ENCRYPT_OP ioctl provides commands to encrypt the images: LAUNCH_START,
 LAUNCH_UPDATE_DATA, LAUNCH_MEASURE and LAUNCH_FINISH. These four commands
 together generate a fresh memory encryption key for the VM, encrypt the boot
-images and provide a measurement than can be used as an attestation of the
+images and provide a measurement than can be used as an attestation of a
 successful launch.
 
 LAUNCH_START is called first to create a cryptographic launch context within
-the firmware. To create this context, guest owner must provides guest policy,
+the firmware. To create this context, guest owner must provide a guest policy,
 its public Diffie-Hellman key (PDH) and session parameters. These inputs
-should be treated as binary blob and must be passed as-is to the SEV firmware.
+should be treated as a binary blob and must be passed as-is to the SEV firmware.
 
-The guest policy is passed as plaintext and hypervisor may able to read it
+The guest policy is passed as plaintext. A hypervisor may choose to read it,
 but should not modify it (any modification of the policy bits will result
 in bad measurement). The guest policy is a 4-byte data structure containing
-several flags that restricts what can be done on running SEV guest.
+several flags that restricts what can be done on a running SEV guest.
 See KM Spec section 3 and 6.2 for more details.
 
 The guest policy can be provided via the 'policy' property (see below)
@@ -40,31 +40,30 @@ The guest policy can be provided via the 'policy' property (see below)
 # ${QEMU} \
    sev-guest,id=sev0,policy=0x1...\
 
-Guest owners provided DH certificate and session parameters will be used to
+The guest owner provided DH certificate and session parameters will be used to
 establish a cryptographic session with the guest owner to negotiate keys used
 for the attestation.
 
-The DH certificate and session blob can be provided via 'dh-cert-file' and
-'session-file' property (see below
+The DH certificate and session blob can be provided via the 'dh-cert-file' and
+'session-file' properties (see below)
 
 # ${QEMU} \
      sev-guest,id=sev0,dh-cert-file=<file1>,session-file=<file2>
 
 LAUNCH_UPDATE_DATA encrypts the memory region using the cryptographic context
-created via LAUNCH_START command. If required, this command can be called
+created via the LAUNCH_START command. If required, this command can be called
 multiple times to encrypt different memory regions. The command also calculates
 the measurement of the memory contents as it encrypts.
 
-LAUNCH_MEASURE command can be used to retrieve the measurement of encrypted
-memory. This measurement is a signature of the memory contents that can be
-sent to the guest owner as an attestation that the memory was encrypted
-correctly by the firmware. The guest owner may wait to provide the guest
-confidential information until it can verify the attestation measurement.
-Since the guest owner knows the initial contents of the guest at boot, the
-attestation measurement can be verified by comparing it to what the guest owner
-expects.
+LAUNCH_MEASURE can be used to retrieve the measurement of encrypted memory.
+This measurement is a signature of the memory contents that can be sent to the
+guest owner as an attestation that the memory was encrypted correctly by the
+firmware. The guest owner may wait to provide the guest confidential information
+until it can verify the attestation measurement. Since the guest owner knows the
+initial contents of the guest at boot, the attestation measurement can be
+verified by comparing it to what the guest owner expects.
 
-LAUNCH_FINISH command finalizes the guest launch and destroy's the cryptographic
+LAUNCH_FINISH finalizes the guest launch and destroys the cryptographic
 context.
 
 See SEV KM API Spec [1] 'Launching a guest' usage flow (Appendix A) for the
@@ -78,10 +77,10 @@ To launch a SEV guest
 
 Debugging
 -----------
-Since memory contents of SEV guest is encrypted hence hypervisor access to the
-guest memory will get a cipher text. If guest policy allows debugging, then
-hypervisor can use DEBUG_DECRYPT and DEBUG_ENCRYPT commands access the guest
-memory region for debug purposes.  This is not supported in QEMU yet.
+Since the memory contents of a SEV guest are encrypted, hypervisor access to
+the guest memory will return cipher text. If the guest policy allows debugging,
+then a hypervisor can use the DEBUG_DECRYPT and DEBUG_ENCRYPT commands to access
+the guest memory region for debug purposes.  This is not supported in QEMU yet.
 
 Snapshot/Restore
 -----------------
-- 
2.31.0



^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH v2 2/3] docs: Add SEV-ES documentation to amd-memory-encryption.txt
  2021-04-23 20:08 [PATCH v2 1/3] doc: Fix some mistakes in the SEV documentation Tom Lendacky
@ 2021-04-23 20:08 ` Tom Lendacky
  2021-04-26 12:33   ` Laszlo Ersek
  2021-04-23 20:08 ` [PATCH v2 3/3] docs/interop/firmware.json: Add SEV-ES support Tom Lendacky
                   ` (3 subsequent siblings)
  4 siblings, 1 reply; 10+ messages in thread
From: Tom Lendacky @ 2021-04-23 20:08 UTC (permalink / raw)
  To: qemu-devel
  Cc: Pavel Hrdina, Daniel P . Berrange, Eduardo Habkost,
	Michal Privoznik, Dr. David Alan Gilbert, Brijesh Singh,
	Paolo Bonzini, Laszlo Ersek

From: Tom Lendacky <thomas.lendacky@amd.com>

Update the amd-memory-encryption.txt file with information about SEV-ES,
including how to launch an SEV-ES guest and some of the differences
between SEV and SEV-ES guests in regards to launching and measuring the
guest.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 docs/amd-memory-encryption.txt | 54 +++++++++++++++++++++++++++++-----
 1 file changed, 47 insertions(+), 7 deletions(-)

diff --git a/docs/amd-memory-encryption.txt b/docs/amd-memory-encryption.txt
index ed85159ea7..ffca382b5f 100644
--- a/docs/amd-memory-encryption.txt
+++ b/docs/amd-memory-encryption.txt
@@ -15,6 +15,13 @@ includes commands for launching, snapshotting, migrating and debugging the
 encrypted guest. These SEV commands can be issued via KVM_MEMORY_ENCRYPT_OP
 ioctls.
 
+Secure Encrypted Virtualization - Encrypted State (SEV-ES) builds on the SEV
+support to additionally protect the guest register state. In order to allow a
+hypervisor to perform functions on behalf of a guest, there is architectural
+support for notifying a guest's operating system when certain types of VMEXITs
+are about to occur. This allows the guest to selectively share information with
+the hypervisor to satisfy the requested function.
+
 Launching
 ---------
 Boot images (such as bios) must be encrypted before a guest can be booted. The
@@ -24,6 +31,9 @@ together generate a fresh memory encryption key for the VM, encrypt the boot
 images and provide a measurement than can be used as an attestation of a
 successful launch.
 
+For a SEV-ES guest, the LAUNCH_UPDATE_VMSA command is also used to encrypt the
+guest register state, or VM save area (VMSA), for all of the guest vCPUs.
+
 LAUNCH_START is called first to create a cryptographic launch context within
 the firmware. To create this context, guest owner must provide a guest policy,
 its public Diffie-Hellman key (PDH) and session parameters. These inputs
@@ -40,6 +50,12 @@ The guest policy can be provided via the 'policy' property (see below)
 # ${QEMU} \
    sev-guest,id=sev0,policy=0x1...\
 
+Setting the "SEV-ES required" policy bit (bit 2) will launch the guest as a
+SEV-ES guest (see below)
+
+# ${QEMU} \
+   sev-guest,id=sev0,policy=0x5...\
+
 The guest owner provided DH certificate and session parameters will be used to
 establish a cryptographic session with the guest owner to negotiate keys used
 for the attestation.
@@ -55,13 +71,19 @@ created via the LAUNCH_START command. If required, this command can be called
 multiple times to encrypt different memory regions. The command also calculates
 the measurement of the memory contents as it encrypts.
 
-LAUNCH_MEASURE can be used to retrieve the measurement of encrypted memory.
-This measurement is a signature of the memory contents that can be sent to the
-guest owner as an attestation that the memory was encrypted correctly by the
-firmware. The guest owner may wait to provide the guest confidential information
-until it can verify the attestation measurement. Since the guest owner knows the
-initial contents of the guest at boot, the attestation measurement can be
-verified by comparing it to what the guest owner expects.
+LAUNCH_UPDATE_VMSA encrypts all the vCPU VMSAs for a SEV-ES guest using the
+cryptographic context created via the LAUNCH_START command. The command also
+calculates the measurement of the VMSAs as it encrypts them.
+
+LAUNCH_MEASURE can be used to retrieve the measurement of encrypted memory and,
+for a SEV-ES guest, encrypted VMSAs. This measurement is a signature of the
+memory contents and, for a SEV-ES guest, the VMSA contents, that can be sent
+to the guest owner as an attestation that the memory and VMSAs were encrypted
+correctly by the firmware. The guest owner may wait to provide the guest
+confidential information until it can verify the attestation measurement.
+Since the guest owner knows the initial contents of the guest at boot, the
+attestation measurement can be verified by comparing it to what the guest owner
+expects.
 
 LAUNCH_FINISH finalizes the guest launch and destroys the cryptographic
 context.
@@ -75,6 +97,22 @@ To launch a SEV guest
     -machine ...,confidential-guest-support=sev0 \
     -object sev-guest,id=sev0,cbitpos=47,reduced-phys-bits=1
 
+To launch a SEV-ES guest
+
+# ${QEMU} \
+    -machine ...,confidential-guest-support=sev0 \
+    -object sev-guest,id=sev0,cbitpos=47,reduced-phys-bits=1,policy=0x5
+
+An SEV-ES guest has some restrictions as compared to a SEV guest. Because the
+guest register state is encrypted and cannot be updated by the VMM/hypervisor,
+a SEV-ES guest:
+ - Does not support SMM - SMM support requires updating the guest register
+   state.
+ - Does not support reboot - a system reset requires updating the guest register
+   state.
+ - Requires in-kernel irqchip - the burden is placed on the hypervisor to
+   manage booting APs.
+
 Debugging
 -----------
 Since the memory contents of a SEV guest are encrypted, hypervisor access to
@@ -101,8 +139,10 @@ Secure Encrypted Virtualization Key Management:
 
 KVM Forum slides:
 http://www.linux-kvm.org/images/7/74/02x08A-Thomas_Lendacky-AMDs_Virtualizatoin_Memory_Encryption_Technology.pdf
+https://www.linux-kvm.org/images/9/94/Extending-Secure-Encrypted-Virtualization-with-SEV-ES-Thomas-Lendacky-AMD.pdf
 
 AMD64 Architecture Programmer's Manual:
    http://support.amd.com/TechDocs/24593.pdf
    SME is section 7.10
    SEV is section 15.34
+   SEV-ES is section 15.35
-- 
2.31.0



^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH v2 3/3] docs/interop/firmware.json: Add SEV-ES support
  2021-04-23 20:08 [PATCH v2 1/3] doc: Fix some mistakes in the SEV documentation Tom Lendacky
  2021-04-23 20:08 ` [PATCH v2 2/3] docs: Add SEV-ES documentation to amd-memory-encryption.txt Tom Lendacky
@ 2021-04-23 20:08 ` Tom Lendacky
  2021-04-26 12:39   ` Laszlo Ersek
  2021-04-26 12:11 ` [PATCH v2 1/3] doc: Fix some mistakes in the SEV documentation Laszlo Ersek
                   ` (2 subsequent siblings)
  4 siblings, 1 reply; 10+ messages in thread
From: Tom Lendacky @ 2021-04-23 20:08 UTC (permalink / raw)
  To: qemu-devel
  Cc: Pavel Hrdina, Daniel P . Berrange, Eduardo Habkost,
	Michal Privoznik, Dr. David Alan Gilbert, Brijesh Singh,
	Paolo Bonzini, Laszlo Ersek

From: Tom Lendacky <thomas.lendacky@amd.com>

Create an enum definition, '@amd-sev-es', for SEV-ES and add documention
for the new enum. Add an example that shows some of the requirements for
SEV-ES, including not having SMM support and the requirement for an
X64-only build.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 docs/interop/firmware.json | 47 +++++++++++++++++++++++++++++++++++++-
 1 file changed, 46 insertions(+), 1 deletion(-)

diff --git a/docs/interop/firmware.json b/docs/interop/firmware.json
index 9d94ccafa9..8d8b0be030 100644
--- a/docs/interop/firmware.json
+++ b/docs/interop/firmware.json
@@ -115,6 +115,12 @@
 #           this feature are documented in
 #           "docs/amd-memory-encryption.txt".
 #
+# @amd-sev-es: The firmware supports running under AMD Secure Encrypted
+#              Virtualization - Encrypted State, as specified in the AMD64
+#              Architecture Programmer's Manual. QEMU command line options
+#              related to this feature are documented in
+#              "docs/amd-memory-encryption.txt".
+#
 # @enrolled-keys: The variable store (NVRAM) template associated with
 #                 the firmware binary has the UEFI Secure Boot
 #                 operational mode turned on, with certificates
@@ -179,7 +185,7 @@
 # Since: 3.0
 ##
 { 'enum' : 'FirmwareFeature',
-  'data' : [ 'acpi-s3', 'acpi-s4', 'amd-sev', 'enrolled-keys',
+  'data' : [ 'acpi-s3', 'acpi-s4', 'amd-sev', 'amd-sev-es', 'enrolled-keys',
              'requires-smm', 'secure-boot', 'verbose-dynamic',
              'verbose-static' ] }
 
@@ -504,6 +510,45 @@
 # }
 #
 # {
+#     "description": "OVMF with SEV-ES support",
+#     "interface-types": [
+#         "uefi"
+#     ],
+#     "mapping": {
+#         "device": "flash",
+#         "executable": {
+#             "filename": "/usr/share/OVMF/OVMF_CODE.fd",
+#             "format": "raw"
+#         },
+#         "nvram-template": {
+#             "filename": "/usr/share/OVMF/OVMF_VARS.fd",
+#             "format": "raw"
+#         }
+#     },
+#     "targets": [
+#         {
+#             "architecture": "x86_64",
+#             "machines": [
+#                 "pc-q35-*"
+#             ]
+#         }
+#     ],
+#     "features": [
+#         "acpi-s3",
+#         "amd-sev",
+#         "amd-sev-es",
+#         "verbose-dynamic"
+#     ],
+#     "tags": [
+#         "-a X64",
+#         "-p OvmfPkg/OvmfPkgX64.dsc",
+#         "-t GCC48",
+#         "-b DEBUG",
+#         "-D FD_SIZE_4MB"
+#     ]
+# }
+#
+# {
 #     "description": "UEFI firmware for ARM64 virtual machines",
 #     "interface-types": [
 #         "uefi"
-- 
2.31.0



^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [PATCH v2 1/3] doc: Fix some mistakes in the SEV documentation
  2021-04-23 20:08 [PATCH v2 1/3] doc: Fix some mistakes in the SEV documentation Tom Lendacky
  2021-04-23 20:08 ` [PATCH v2 2/3] docs: Add SEV-ES documentation to amd-memory-encryption.txt Tom Lendacky
  2021-04-23 20:08 ` [PATCH v2 3/3] docs/interop/firmware.json: Add SEV-ES support Tom Lendacky
@ 2021-04-26 12:11 ` Laszlo Ersek
  2021-06-02 19:19 ` Tom Lendacky
  2021-06-02 20:07 ` Connor Kuehl
  4 siblings, 0 replies; 10+ messages in thread
From: Laszlo Ersek @ 2021-04-26 12:11 UTC (permalink / raw)
  To: Tom Lendacky, qemu-devel
  Cc: Pavel Hrdina, Daniel P . Berrange, Eduardo Habkost,
	Michal Privoznik, Dr. David Alan Gilbert, Brijesh Singh,
	Paolo Bonzini

On 04/23/21 22:08, Tom Lendacky wrote:
> From: Tom Lendacky <thomas.lendacky@amd.com>
> 
> Fix some spelling and grammar mistakes in the amd-memory-encryption.txt
> file. No new information added.
> 
> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
> ---
>  docs/amd-memory-encryption.txt | 59 +++++++++++++++++-----------------
>  1 file changed, 29 insertions(+), 30 deletions(-)
> 
> diff --git a/docs/amd-memory-encryption.txt b/docs/amd-memory-encryption.txt
> index 145896aec7..ed85159ea7 100644
> --- a/docs/amd-memory-encryption.txt
> +++ b/docs/amd-memory-encryption.txt
> @@ -1,38 +1,38 @@
>  Secure Encrypted Virtualization (SEV) is a feature found on AMD processors.
>  
>  SEV is an extension to the AMD-V architecture which supports running encrypted
> -virtual machine (VMs) under the control of KVM. Encrypted VMs have their pages
> +virtual machines (VMs) under the control of KVM. Encrypted VMs have their pages
>  (code and data) secured such that only the guest itself has access to the
>  unencrypted version. Each encrypted VM is associated with a unique encryption
> -key; if its data is accessed to a different entity using a different key the
> +key; if its data is accessed by a different entity using a different key the
>  encrypted guests data will be incorrectly decrypted, leading to unintelligible
>  data.
>  
> -The key management of this feature is handled by separate processor known as
> -AMD secure processor (AMD-SP) which is present in AMD SOCs. Firmware running
> -inside the AMD-SP provide commands to support common VM lifecycle. This
> +Key management for this feature is handled by a separate processor known as the
> +AMD secure processor (AMD-SP), which is present in AMD SOCs. Firmware running
> +inside the AMD-SP provides commands to support a common VM lifecycle. This
>  includes commands for launching, snapshotting, migrating and debugging the
> -encrypted guest. Those SEV command can be issued via KVM_MEMORY_ENCRYPT_OP
> +encrypted guest. These SEV commands can be issued via KVM_MEMORY_ENCRYPT_OP
>  ioctls.
>  
>  Launching
>  ---------
> -Boot images (such as bios) must be encrypted before guest can be booted.
> -MEMORY_ENCRYPT_OP ioctl provides commands to encrypt the images :LAUNCH_START,
> +Boot images (such as bios) must be encrypted before a guest can be booted. The
> +MEMORY_ENCRYPT_OP ioctl provides commands to encrypt the images: LAUNCH_START,
>  LAUNCH_UPDATE_DATA, LAUNCH_MEASURE and LAUNCH_FINISH. These four commands
>  together generate a fresh memory encryption key for the VM, encrypt the boot
> -images and provide a measurement than can be used as an attestation of the
> +images and provide a measurement than can be used as an attestation of a
>  successful launch.
>  
>  LAUNCH_START is called first to create a cryptographic launch context within
> -the firmware. To create this context, guest owner must provides guest policy,
> +the firmware. To create this context, guest owner must provide a guest policy,
>  its public Diffie-Hellman key (PDH) and session parameters. These inputs
> -should be treated as binary blob and must be passed as-is to the SEV firmware.
> +should be treated as a binary blob and must be passed as-is to the SEV firmware.
>  
> -The guest policy is passed as plaintext and hypervisor may able to read it
> +The guest policy is passed as plaintext. A hypervisor may choose to read it,
>  but should not modify it (any modification of the policy bits will result
>  in bad measurement). The guest policy is a 4-byte data structure containing
> -several flags that restricts what can be done on running SEV guest.
> +several flags that restricts what can be done on a running SEV guest.
>  See KM Spec section 3 and 6.2 for more details.
>  
>  The guest policy can be provided via the 'policy' property (see below)
> @@ -40,31 +40,30 @@ The guest policy can be provided via the 'policy' property (see below)
>  # ${QEMU} \
>     sev-guest,id=sev0,policy=0x1...\
>  
> -Guest owners provided DH certificate and session parameters will be used to
> +The guest owner provided DH certificate and session parameters will be used to
>  establish a cryptographic session with the guest owner to negotiate keys used
>  for the attestation.
>  
> -The DH certificate and session blob can be provided via 'dh-cert-file' and
> -'session-file' property (see below
> +The DH certificate and session blob can be provided via the 'dh-cert-file' and
> +'session-file' properties (see below)
>  
>  # ${QEMU} \
>       sev-guest,id=sev0,dh-cert-file=<file1>,session-file=<file2>
>  
>  LAUNCH_UPDATE_DATA encrypts the memory region using the cryptographic context
> -created via LAUNCH_START command. If required, this command can be called
> +created via the LAUNCH_START command. If required, this command can be called
>  multiple times to encrypt different memory regions. The command also calculates
>  the measurement of the memory contents as it encrypts.
>  
> -LAUNCH_MEASURE command can be used to retrieve the measurement of encrypted
> -memory. This measurement is a signature of the memory contents that can be
> -sent to the guest owner as an attestation that the memory was encrypted
> -correctly by the firmware. The guest owner may wait to provide the guest
> -confidential information until it can verify the attestation measurement.
> -Since the guest owner knows the initial contents of the guest at boot, the
> -attestation measurement can be verified by comparing it to what the guest owner
> -expects.
> +LAUNCH_MEASURE can be used to retrieve the measurement of encrypted memory.
> +This measurement is a signature of the memory contents that can be sent to the
> +guest owner as an attestation that the memory was encrypted correctly by the
> +firmware. The guest owner may wait to provide the guest confidential information
> +until it can verify the attestation measurement. Since the guest owner knows the
> +initial contents of the guest at boot, the attestation measurement can be
> +verified by comparing it to what the guest owner expects.
>  
> -LAUNCH_FINISH command finalizes the guest launch and destroy's the cryptographic
> +LAUNCH_FINISH finalizes the guest launch and destroys the cryptographic
>  context.
>  
>  See SEV KM API Spec [1] 'Launching a guest' usage flow (Appendix A) for the
> @@ -78,10 +77,10 @@ To launch a SEV guest
>  
>  Debugging
>  -----------
> -Since memory contents of SEV guest is encrypted hence hypervisor access to the
> -guest memory will get a cipher text. If guest policy allows debugging, then
> -hypervisor can use DEBUG_DECRYPT and DEBUG_ENCRYPT commands access the guest
> -memory region for debug purposes.  This is not supported in QEMU yet.
> +Since the memory contents of a SEV guest are encrypted, hypervisor access to
> +the guest memory will return cipher text. If the guest policy allows debugging,
> +then a hypervisor can use the DEBUG_DECRYPT and DEBUG_ENCRYPT commands to access
> +the guest memory region for debug purposes.  This is not supported in QEMU yet.
>  
>  Snapshot/Restore
>  -----------------
> 

Reviewed-by: Laszlo Ersek <lersek@redhat.com>



^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [PATCH v2 2/3] docs: Add SEV-ES documentation to amd-memory-encryption.txt
  2021-04-23 20:08 ` [PATCH v2 2/3] docs: Add SEV-ES documentation to amd-memory-encryption.txt Tom Lendacky
@ 2021-04-26 12:33   ` Laszlo Ersek
  0 siblings, 0 replies; 10+ messages in thread
From: Laszlo Ersek @ 2021-04-26 12:33 UTC (permalink / raw)
  To: Tom Lendacky, qemu-devel
  Cc: Pavel Hrdina, Daniel P . Berrange, Eduardo Habkost,
	Michal Privoznik, Dr. David Alan Gilbert, Brijesh Singh,
	Paolo Bonzini

On 04/23/21 22:08, Tom Lendacky wrote:
> From: Tom Lendacky <thomas.lendacky@amd.com>
> 
> Update the amd-memory-encryption.txt file with information about SEV-ES,
> including how to launch an SEV-ES guest and some of the differences
> between SEV and SEV-ES guests in regards to launching and measuring the
> guest.
> 
> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
> ---
>  docs/amd-memory-encryption.txt | 54 +++++++++++++++++++++++++++++-----
>  1 file changed, 47 insertions(+), 7 deletions(-)
> 
> diff --git a/docs/amd-memory-encryption.txt b/docs/amd-memory-encryption.txt
> index ed85159ea7..ffca382b5f 100644
> --- a/docs/amd-memory-encryption.txt
> +++ b/docs/amd-memory-encryption.txt
> @@ -15,6 +15,13 @@ includes commands for launching, snapshotting, migrating and debugging the
>  encrypted guest. These SEV commands can be issued via KVM_MEMORY_ENCRYPT_OP
>  ioctls.
>  
> +Secure Encrypted Virtualization - Encrypted State (SEV-ES) builds on the SEV
> +support to additionally protect the guest register state. In order to allow a
> +hypervisor to perform functions on behalf of a guest, there is architectural
> +support for notifying a guest's operating system when certain types of VMEXITs
> +are about to occur. This allows the guest to selectively share information with
> +the hypervisor to satisfy the requested function.
> +
>  Launching
>  ---------
>  Boot images (such as bios) must be encrypted before a guest can be booted. The
> @@ -24,6 +31,9 @@ together generate a fresh memory encryption key for the VM, encrypt the boot
>  images and provide a measurement than can be used as an attestation of a
>  successful launch.
>  
> +For a SEV-ES guest, the LAUNCH_UPDATE_VMSA command is also used to encrypt the
> +guest register state, or VM save area (VMSA), for all of the guest vCPUs.
> +
>  LAUNCH_START is called first to create a cryptographic launch context within
>  the firmware. To create this context, guest owner must provide a guest policy,
>  its public Diffie-Hellman key (PDH) and session parameters. These inputs
> @@ -40,6 +50,12 @@ The guest policy can be provided via the 'policy' property (see below)
>  # ${QEMU} \
>     sev-guest,id=sev0,policy=0x1...\
>  
> +Setting the "SEV-ES required" policy bit (bit 2) will launch the guest as a
> +SEV-ES guest (see below)
> +
> +# ${QEMU} \
> +   sev-guest,id=sev0,policy=0x5...\
> +
>  The guest owner provided DH certificate and session parameters will be used to
>  establish a cryptographic session with the guest owner to negotiate keys used
>  for the attestation.
> @@ -55,13 +71,19 @@ created via the LAUNCH_START command. If required, this command can be called
>  multiple times to encrypt different memory regions. The command also calculates
>  the measurement of the memory contents as it encrypts.
>  
> -LAUNCH_MEASURE can be used to retrieve the measurement of encrypted memory.
> -This measurement is a signature of the memory contents that can be sent to the
> -guest owner as an attestation that the memory was encrypted correctly by the
> -firmware. The guest owner may wait to provide the guest confidential information
> -until it can verify the attestation measurement. Since the guest owner knows the
> -initial contents of the guest at boot, the attestation measurement can be
> -verified by comparing it to what the guest owner expects.
> +LAUNCH_UPDATE_VMSA encrypts all the vCPU VMSAs for a SEV-ES guest using the
> +cryptographic context created via the LAUNCH_START command. The command also
> +calculates the measurement of the VMSAs as it encrypts them.
> +
> +LAUNCH_MEASURE can be used to retrieve the measurement of encrypted memory and,
> +for a SEV-ES guest, encrypted VMSAs. This measurement is a signature of the
> +memory contents and, for a SEV-ES guest, the VMSA contents, that can be sent
> +to the guest owner as an attestation that the memory and VMSAs were encrypted
> +correctly by the firmware. The guest owner may wait to provide the guest
> +confidential information until it can verify the attestation measurement.
> +Since the guest owner knows the initial contents of the guest at boot, the
> +attestation measurement can be verified by comparing it to what the guest owner
> +expects.
>  
>  LAUNCH_FINISH finalizes the guest launch and destroys the cryptographic
>  context.
> @@ -75,6 +97,22 @@ To launch a SEV guest
>      -machine ...,confidential-guest-support=sev0 \
>      -object sev-guest,id=sev0,cbitpos=47,reduced-phys-bits=1
>  
> +To launch a SEV-ES guest
> +
> +# ${QEMU} \
> +    -machine ...,confidential-guest-support=sev0 \
> +    -object sev-guest,id=sev0,cbitpos=47,reduced-phys-bits=1,policy=0x5
> +
> +An SEV-ES guest has some restrictions as compared to a SEV guest. Because the
> +guest register state is encrypted and cannot be updated by the VMM/hypervisor,
> +a SEV-ES guest:
> + - Does not support SMM - SMM support requires updating the guest register
> +   state.
> + - Does not support reboot - a system reset requires updating the guest register
> +   state.
> + - Requires in-kernel irqchip - the burden is placed on the hypervisor to
> +   manage booting APs.
> +
>  Debugging
>  -----------
>  Since the memory contents of a SEV guest are encrypted, hypervisor access to
> @@ -101,8 +139,10 @@ Secure Encrypted Virtualization Key Management:
>  
>  KVM Forum slides:
>  http://www.linux-kvm.org/images/7/74/02x08A-Thomas_Lendacky-AMDs_Virtualizatoin_Memory_Encryption_Technology.pdf
> +https://www.linux-kvm.org/images/9/94/Extending-Secure-Encrypted-Virtualization-with-SEV-ES-Thomas-Lendacky-AMD.pdf
>  
>  AMD64 Architecture Programmer's Manual:
>     http://support.amd.com/TechDocs/24593.pdf
>     SME is section 7.10
>     SEV is section 15.34
> +   SEV-ES is section 15.35
> 

Looks good to me.

Acked-by: Laszlo Ersek <lersek@redhat.com>



^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [PATCH v2 3/3] docs/interop/firmware.json: Add SEV-ES support
  2021-04-23 20:08 ` [PATCH v2 3/3] docs/interop/firmware.json: Add SEV-ES support Tom Lendacky
@ 2021-04-26 12:39   ` Laszlo Ersek
  0 siblings, 0 replies; 10+ messages in thread
From: Laszlo Ersek @ 2021-04-26 12:39 UTC (permalink / raw)
  To: Tom Lendacky, qemu-devel
  Cc: Pavel Hrdina, Daniel P . Berrange, Eduardo Habkost,
	Michal Privoznik, Dr. David Alan Gilbert, Brijesh Singh,
	Paolo Bonzini

On 04/23/21 22:08, Tom Lendacky wrote:
> From: Tom Lendacky <thomas.lendacky@amd.com>
> 
> Create an enum definition, '@amd-sev-es', for SEV-ES and add documention
> for the new enum. Add an example that shows some of the requirements for
> SEV-ES, including not having SMM support and the requirement for an
> X64-only build.
> 
> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
> ---
>  docs/interop/firmware.json | 47 +++++++++++++++++++++++++++++++++++++-
>  1 file changed, 46 insertions(+), 1 deletion(-)
> 
> diff --git a/docs/interop/firmware.json b/docs/interop/firmware.json
> index 9d94ccafa9..8d8b0be030 100644
> --- a/docs/interop/firmware.json
> +++ b/docs/interop/firmware.json
> @@ -115,6 +115,12 @@
>  #           this feature are documented in
>  #           "docs/amd-memory-encryption.txt".
>  #
> +# @amd-sev-es: The firmware supports running under AMD Secure Encrypted
> +#              Virtualization - Encrypted State, as specified in the AMD64
> +#              Architecture Programmer's Manual. QEMU command line options
> +#              related to this feature are documented in
> +#              "docs/amd-memory-encryption.txt".
> +#
>  # @enrolled-keys: The variable store (NVRAM) template associated with
>  #                 the firmware binary has the UEFI Secure Boot
>  #                 operational mode turned on, with certificates
> @@ -179,7 +185,7 @@
>  # Since: 3.0
>  ##
>  { 'enum' : 'FirmwareFeature',
> -  'data' : [ 'acpi-s3', 'acpi-s4', 'amd-sev', 'enrolled-keys',
> +  'data' : [ 'acpi-s3', 'acpi-s4', 'amd-sev', 'amd-sev-es', 'enrolled-keys',
>               'requires-smm', 'secure-boot', 'verbose-dynamic',
>               'verbose-static' ] }
>  
> @@ -504,6 +510,45 @@
>  # }
>  #
>  # {
> +#     "description": "OVMF with SEV-ES support",
> +#     "interface-types": [
> +#         "uefi"
> +#     ],
> +#     "mapping": {
> +#         "device": "flash",
> +#         "executable": {
> +#             "filename": "/usr/share/OVMF/OVMF_CODE.fd",
> +#             "format": "raw"
> +#         },
> +#         "nvram-template": {
> +#             "filename": "/usr/share/OVMF/OVMF_VARS.fd",
> +#             "format": "raw"
> +#         }
> +#     },
> +#     "targets": [
> +#         {
> +#             "architecture": "x86_64",
> +#             "machines": [
> +#                 "pc-q35-*"
> +#             ]
> +#         }
> +#     ],
> +#     "features": [
> +#         "acpi-s3",
> +#         "amd-sev",
> +#         "amd-sev-es",
> +#         "verbose-dynamic"
> +#     ],
> +#     "tags": [
> +#         "-a X64",
> +#         "-p OvmfPkg/OvmfPkgX64.dsc",
> +#         "-t GCC48",
> +#         "-b DEBUG",
> +#         "-D FD_SIZE_4MB"
> +#     ]
> +# }
> +#
> +# {
>  #     "description": "UEFI firmware for ARM64 virtual machines",
>  #     "interface-types": [
>  #         "uefi"
> 

Reviewed-by: Laszlo Ersek <lersek@redhat.com>

Thanks!
Laszlo



^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [PATCH v2 1/3] doc: Fix some mistakes in the SEV documentation
  2021-04-23 20:08 [PATCH v2 1/3] doc: Fix some mistakes in the SEV documentation Tom Lendacky
                   ` (2 preceding siblings ...)
  2021-04-26 12:11 ` [PATCH v2 1/3] doc: Fix some mistakes in the SEV documentation Laszlo Ersek
@ 2021-06-02 19:19 ` Tom Lendacky
  2021-06-03  8:29   ` Laszlo Ersek
  2021-06-02 20:07 ` Connor Kuehl
  4 siblings, 1 reply; 10+ messages in thread
From: Tom Lendacky @ 2021-06-02 19:19 UTC (permalink / raw)
  To: qemu-devel
  Cc: Daniel P . Berrange, Paolo Bonzini, Laszlo Ersek,
	Dr. David Alan Gilbert, Eduardo Habkost, Pavel Hrdina,
	Michal Privoznik, Brijesh Singh

Just a quick ping on this series...

Thanks,
Tom

On 4/23/21 3:08 PM, Tom Lendacky wrote:
> From: Tom Lendacky <thomas.lendacky@amd.com>
> 
> Fix some spelling and grammar mistakes in the amd-memory-encryption.txt
> file. No new information added.
> 
> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
> ---
>  docs/amd-memory-encryption.txt | 59 +++++++++++++++++-----------------
>  1 file changed, 29 insertions(+), 30 deletions(-)
> 
> diff --git a/docs/amd-memory-encryption.txt b/docs/amd-memory-encryption.txt
> index 145896aec7..ed85159ea7 100644
> --- a/docs/amd-memory-encryption.txt
> +++ b/docs/amd-memory-encryption.txt
> @@ -1,38 +1,38 @@
>  Secure Encrypted Virtualization (SEV) is a feature found on AMD processors.
>  
>  SEV is an extension to the AMD-V architecture which supports running encrypted
> -virtual machine (VMs) under the control of KVM. Encrypted VMs have their pages
> +virtual machines (VMs) under the control of KVM. Encrypted VMs have their pages
>  (code and data) secured such that only the guest itself has access to the
>  unencrypted version. Each encrypted VM is associated with a unique encryption
> -key; if its data is accessed to a different entity using a different key the
> +key; if its data is accessed by a different entity using a different key the
>  encrypted guests data will be incorrectly decrypted, leading to unintelligible
>  data.
>  
> -The key management of this feature is handled by separate processor known as
> -AMD secure processor (AMD-SP) which is present in AMD SOCs. Firmware running
> -inside the AMD-SP provide commands to support common VM lifecycle. This
> +Key management for this feature is handled by a separate processor known as the
> +AMD secure processor (AMD-SP), which is present in AMD SOCs. Firmware running
> +inside the AMD-SP provides commands to support a common VM lifecycle. This
>  includes commands for launching, snapshotting, migrating and debugging the
> -encrypted guest. Those SEV command can be issued via KVM_MEMORY_ENCRYPT_OP
> +encrypted guest. These SEV commands can be issued via KVM_MEMORY_ENCRYPT_OP
>  ioctls.
>  
>  Launching
>  ---------
> -Boot images (such as bios) must be encrypted before guest can be booted.
> -MEMORY_ENCRYPT_OP ioctl provides commands to encrypt the images :LAUNCH_START,
> +Boot images (such as bios) must be encrypted before a guest can be booted. The
> +MEMORY_ENCRYPT_OP ioctl provides commands to encrypt the images: LAUNCH_START,
>  LAUNCH_UPDATE_DATA, LAUNCH_MEASURE and LAUNCH_FINISH. These four commands
>  together generate a fresh memory encryption key for the VM, encrypt the boot
> -images and provide a measurement than can be used as an attestation of the
> +images and provide a measurement than can be used as an attestation of a
>  successful launch.
>  
>  LAUNCH_START is called first to create a cryptographic launch context within
> -the firmware. To create this context, guest owner must provides guest policy,
> +the firmware. To create this context, guest owner must provide a guest policy,
>  its public Diffie-Hellman key (PDH) and session parameters. These inputs
> -should be treated as binary blob and must be passed as-is to the SEV firmware.
> +should be treated as a binary blob and must be passed as-is to the SEV firmware.
>  
> -The guest policy is passed as plaintext and hypervisor may able to read it
> +The guest policy is passed as plaintext. A hypervisor may choose to read it,
>  but should not modify it (any modification of the policy bits will result
>  in bad measurement). The guest policy is a 4-byte data structure containing
> -several flags that restricts what can be done on running SEV guest.
> +several flags that restricts what can be done on a running SEV guest.
>  See KM Spec section 3 and 6.2 for more details.
>  
>  The guest policy can be provided via the 'policy' property (see below)
> @@ -40,31 +40,30 @@ The guest policy can be provided via the 'policy' property (see below)
>  # ${QEMU} \
>     sev-guest,id=sev0,policy=0x1...\
>  
> -Guest owners provided DH certificate and session parameters will be used to
> +The guest owner provided DH certificate and session parameters will be used to
>  establish a cryptographic session with the guest owner to negotiate keys used
>  for the attestation.
>  
> -The DH certificate and session blob can be provided via 'dh-cert-file' and
> -'session-file' property (see below
> +The DH certificate and session blob can be provided via the 'dh-cert-file' and
> +'session-file' properties (see below)
>  
>  # ${QEMU} \
>       sev-guest,id=sev0,dh-cert-file=<file1>,session-file=<file2>
>  
>  LAUNCH_UPDATE_DATA encrypts the memory region using the cryptographic context
> -created via LAUNCH_START command. If required, this command can be called
> +created via the LAUNCH_START command. If required, this command can be called
>  multiple times to encrypt different memory regions. The command also calculates
>  the measurement of the memory contents as it encrypts.
>  
> -LAUNCH_MEASURE command can be used to retrieve the measurement of encrypted
> -memory. This measurement is a signature of the memory contents that can be
> -sent to the guest owner as an attestation that the memory was encrypted
> -correctly by the firmware. The guest owner may wait to provide the guest
> -confidential information until it can verify the attestation measurement.
> -Since the guest owner knows the initial contents of the guest at boot, the
> -attestation measurement can be verified by comparing it to what the guest owner
> -expects.
> +LAUNCH_MEASURE can be used to retrieve the measurement of encrypted memory.
> +This measurement is a signature of the memory contents that can be sent to the
> +guest owner as an attestation that the memory was encrypted correctly by the
> +firmware. The guest owner may wait to provide the guest confidential information
> +until it can verify the attestation measurement. Since the guest owner knows the
> +initial contents of the guest at boot, the attestation measurement can be
> +verified by comparing it to what the guest owner expects.
>  
> -LAUNCH_FINISH command finalizes the guest launch and destroy's the cryptographic
> +LAUNCH_FINISH finalizes the guest launch and destroys the cryptographic
>  context.
>  
>  See SEV KM API Spec [1] 'Launching a guest' usage flow (Appendix A) for the
> @@ -78,10 +77,10 @@ To launch a SEV guest
>  
>  Debugging
>  -----------
> -Since memory contents of SEV guest is encrypted hence hypervisor access to the
> -guest memory will get a cipher text. If guest policy allows debugging, then
> -hypervisor can use DEBUG_DECRYPT and DEBUG_ENCRYPT commands access the guest
> -memory region for debug purposes.  This is not supported in QEMU yet.
> +Since the memory contents of a SEV guest are encrypted, hypervisor access to
> +the guest memory will return cipher text. If the guest policy allows debugging,
> +then a hypervisor can use the DEBUG_DECRYPT and DEBUG_ENCRYPT commands to access
> +the guest memory region for debug purposes.  This is not supported in QEMU yet.
>  
>  Snapshot/Restore
>  -----------------
> 


^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [PATCH v2 1/3] doc: Fix some mistakes in the SEV documentation
  2021-04-23 20:08 [PATCH v2 1/3] doc: Fix some mistakes in the SEV documentation Tom Lendacky
                   ` (3 preceding siblings ...)
  2021-06-02 19:19 ` Tom Lendacky
@ 2021-06-02 20:07 ` Connor Kuehl
  4 siblings, 0 replies; 10+ messages in thread
From: Connor Kuehl @ 2021-06-02 20:07 UTC (permalink / raw)
  To: Tom Lendacky, qemu-devel
  Cc: Pavel Hrdina, Daniel P . Berrange, Eduardo Habkost,
	Michal Privoznik, Dr. David Alan Gilbert, Paolo Bonzini,
	Brijesh Singh, Laszlo Ersek

On 4/23/21 3:08 PM, Tom Lendacky wrote:
> From: Tom Lendacky <thomas.lendacky@amd.com>
> 
> Fix some spelling and grammar mistakes in the amd-memory-encryption.txt
> file. No new information added.
> 
> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>

For the series:

Reviewed-by: Connor Kuehl <ckuehl@redhat.com>



^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [PATCH v2 1/3] doc: Fix some mistakes in the SEV documentation
  2021-06-02 19:19 ` Tom Lendacky
@ 2021-06-03  8:29   ` Laszlo Ersek
  2021-06-03 19:54     ` Eduardo Habkost
  0 siblings, 1 reply; 10+ messages in thread
From: Laszlo Ersek @ 2021-06-03  8:29 UTC (permalink / raw)
  To: Tom Lendacky, qemu-devel
  Cc: Pavel Hrdina, Daniel P . Berrange, Eduardo Habkost,
	Michal Privoznik, Dr. David Alan Gilbert, Brijesh Singh,
	Paolo Bonzini

On 06/02/21 21:19, Tom Lendacky wrote:
> Just a quick ping on this series...

Right, I'm unsure who is supposed to merge this... Do you remember who
usually merges the SEV-related patch series (plural)?

Thanks
Laszlo

> 
> Thanks,
> Tom
> 
> On 4/23/21 3:08 PM, Tom Lendacky wrote:
>> From: Tom Lendacky <thomas.lendacky@amd.com>
>>
>> Fix some spelling and grammar mistakes in the amd-memory-encryption.txt
>> file. No new information added.
>>
>> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
>> ---
>>  docs/amd-memory-encryption.txt | 59 +++++++++++++++++-----------------
>>  1 file changed, 29 insertions(+), 30 deletions(-)
>>
>> diff --git a/docs/amd-memory-encryption.txt b/docs/amd-memory-encryption.txt
>> index 145896aec7..ed85159ea7 100644
>> --- a/docs/amd-memory-encryption.txt
>> +++ b/docs/amd-memory-encryption.txt
>> @@ -1,38 +1,38 @@
>>  Secure Encrypted Virtualization (SEV) is a feature found on AMD processors.
>>  
>>  SEV is an extension to the AMD-V architecture which supports running encrypted
>> -virtual machine (VMs) under the control of KVM. Encrypted VMs have their pages
>> +virtual machines (VMs) under the control of KVM. Encrypted VMs have their pages
>>  (code and data) secured such that only the guest itself has access to the
>>  unencrypted version. Each encrypted VM is associated with a unique encryption
>> -key; if its data is accessed to a different entity using a different key the
>> +key; if its data is accessed by a different entity using a different key the
>>  encrypted guests data will be incorrectly decrypted, leading to unintelligible
>>  data.
>>  
>> -The key management of this feature is handled by separate processor known as
>> -AMD secure processor (AMD-SP) which is present in AMD SOCs. Firmware running
>> -inside the AMD-SP provide commands to support common VM lifecycle. This
>> +Key management for this feature is handled by a separate processor known as the
>> +AMD secure processor (AMD-SP), which is present in AMD SOCs. Firmware running
>> +inside the AMD-SP provides commands to support a common VM lifecycle. This
>>  includes commands for launching, snapshotting, migrating and debugging the
>> -encrypted guest. Those SEV command can be issued via KVM_MEMORY_ENCRYPT_OP
>> +encrypted guest. These SEV commands can be issued via KVM_MEMORY_ENCRYPT_OP
>>  ioctls.
>>  
>>  Launching
>>  ---------
>> -Boot images (such as bios) must be encrypted before guest can be booted.
>> -MEMORY_ENCRYPT_OP ioctl provides commands to encrypt the images :LAUNCH_START,
>> +Boot images (such as bios) must be encrypted before a guest can be booted. The
>> +MEMORY_ENCRYPT_OP ioctl provides commands to encrypt the images: LAUNCH_START,
>>  LAUNCH_UPDATE_DATA, LAUNCH_MEASURE and LAUNCH_FINISH. These four commands
>>  together generate a fresh memory encryption key for the VM, encrypt the boot
>> -images and provide a measurement than can be used as an attestation of the
>> +images and provide a measurement than can be used as an attestation of a
>>  successful launch.
>>  
>>  LAUNCH_START is called first to create a cryptographic launch context within
>> -the firmware. To create this context, guest owner must provides guest policy,
>> +the firmware. To create this context, guest owner must provide a guest policy,
>>  its public Diffie-Hellman key (PDH) and session parameters. These inputs
>> -should be treated as binary blob and must be passed as-is to the SEV firmware.
>> +should be treated as a binary blob and must be passed as-is to the SEV firmware.
>>  
>> -The guest policy is passed as plaintext and hypervisor may able to read it
>> +The guest policy is passed as plaintext. A hypervisor may choose to read it,
>>  but should not modify it (any modification of the policy bits will result
>>  in bad measurement). The guest policy is a 4-byte data structure containing
>> -several flags that restricts what can be done on running SEV guest.
>> +several flags that restricts what can be done on a running SEV guest.
>>  See KM Spec section 3 and 6.2 for more details.
>>  
>>  The guest policy can be provided via the 'policy' property (see below)
>> @@ -40,31 +40,30 @@ The guest policy can be provided via the 'policy' property (see below)
>>  # ${QEMU} \
>>     sev-guest,id=sev0,policy=0x1...\
>>  
>> -Guest owners provided DH certificate and session parameters will be used to
>> +The guest owner provided DH certificate and session parameters will be used to
>>  establish a cryptographic session with the guest owner to negotiate keys used
>>  for the attestation.
>>  
>> -The DH certificate and session blob can be provided via 'dh-cert-file' and
>> -'session-file' property (see below
>> +The DH certificate and session blob can be provided via the 'dh-cert-file' and
>> +'session-file' properties (see below)
>>  
>>  # ${QEMU} \
>>       sev-guest,id=sev0,dh-cert-file=<file1>,session-file=<file2>
>>  
>>  LAUNCH_UPDATE_DATA encrypts the memory region using the cryptographic context
>> -created via LAUNCH_START command. If required, this command can be called
>> +created via the LAUNCH_START command. If required, this command can be called
>>  multiple times to encrypt different memory regions. The command also calculates
>>  the measurement of the memory contents as it encrypts.
>>  
>> -LAUNCH_MEASURE command can be used to retrieve the measurement of encrypted
>> -memory. This measurement is a signature of the memory contents that can be
>> -sent to the guest owner as an attestation that the memory was encrypted
>> -correctly by the firmware. The guest owner may wait to provide the guest
>> -confidential information until it can verify the attestation measurement.
>> -Since the guest owner knows the initial contents of the guest at boot, the
>> -attestation measurement can be verified by comparing it to what the guest owner
>> -expects.
>> +LAUNCH_MEASURE can be used to retrieve the measurement of encrypted memory.
>> +This measurement is a signature of the memory contents that can be sent to the
>> +guest owner as an attestation that the memory was encrypted correctly by the
>> +firmware. The guest owner may wait to provide the guest confidential information
>> +until it can verify the attestation measurement. Since the guest owner knows the
>> +initial contents of the guest at boot, the attestation measurement can be
>> +verified by comparing it to what the guest owner expects.
>>  
>> -LAUNCH_FINISH command finalizes the guest launch and destroy's the cryptographic
>> +LAUNCH_FINISH finalizes the guest launch and destroys the cryptographic
>>  context.
>>  
>>  See SEV KM API Spec [1] 'Launching a guest' usage flow (Appendix A) for the
>> @@ -78,10 +77,10 @@ To launch a SEV guest
>>  
>>  Debugging
>>  -----------
>> -Since memory contents of SEV guest is encrypted hence hypervisor access to the
>> -guest memory will get a cipher text. If guest policy allows debugging, then
>> -hypervisor can use DEBUG_DECRYPT and DEBUG_ENCRYPT commands access the guest
>> -memory region for debug purposes.  This is not supported in QEMU yet.
>> +Since the memory contents of a SEV guest are encrypted, hypervisor access to
>> +the guest memory will return cipher text. If the guest policy allows debugging,
>> +then a hypervisor can use the DEBUG_DECRYPT and DEBUG_ENCRYPT commands to access
>> +the guest memory region for debug purposes.  This is not supported in QEMU yet.
>>  
>>  Snapshot/Restore
>>  -----------------
>>
> 



^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [PATCH v2 1/3] doc: Fix some mistakes in the SEV documentation
  2021-06-03  8:29   ` Laszlo Ersek
@ 2021-06-03 19:54     ` Eduardo Habkost
  0 siblings, 0 replies; 10+ messages in thread
From: Eduardo Habkost @ 2021-06-03 19:54 UTC (permalink / raw)
  To: Laszlo Ersek
  Cc: Tom Lendacky, Pavel Hrdina, Daniel P . Berrange,
	Michal Privoznik, qemu-devel, Dr. David Alan Gilbert,
	Brijesh Singh, Paolo Bonzini

On Thu, Jun 03, 2021 at 10:29:35AM +0200, Laszlo Ersek wrote:
> On 06/02/21 21:19, Tom Lendacky wrote:
> > Just a quick ping on this series...
> 
> Right, I'm unsure who is supposed to merge this... Do you remember who
> usually merges the SEV-related patch series (plural)?

I'm queueing this series by now, but we truly need somebody to
volunteer as maintainer of the SEV code.

-- 
Eduardo



^ permalink raw reply	[flat|nested] 10+ messages in thread

end of thread, other threads:[~2021-06-03 19:55 UTC | newest]

Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-04-23 20:08 [PATCH v2 1/3] doc: Fix some mistakes in the SEV documentation Tom Lendacky
2021-04-23 20:08 ` [PATCH v2 2/3] docs: Add SEV-ES documentation to amd-memory-encryption.txt Tom Lendacky
2021-04-26 12:33   ` Laszlo Ersek
2021-04-23 20:08 ` [PATCH v2 3/3] docs/interop/firmware.json: Add SEV-ES support Tom Lendacky
2021-04-26 12:39   ` Laszlo Ersek
2021-04-26 12:11 ` [PATCH v2 1/3] doc: Fix some mistakes in the SEV documentation Laszlo Ersek
2021-06-02 19:19 ` Tom Lendacky
2021-06-03  8:29   ` Laszlo Ersek
2021-06-03 19:54     ` Eduardo Habkost
2021-06-02 20:07 ` Connor Kuehl

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