[v2,0/8] Support ACPI PSP on Hyper-V

Message

Jeremi Piotrowski Feb. 13, 2023, 9:24 a.m. UTC

This patch series introduces support for discovering AMD's PSP from an ACPI
table and extends the CCP driver to allow binding to that device on x86. This
method of PSP discovery is used on Hyper-V when SNP isolation support is
exposed to the guest. There is no ACPI node associated with this PSP, so after
parsing the ASPT it is registered with the system as a platform_device.

I thought about putting psp.c in arch/x86/coco, but that directory is meant for
the (confidential) guest side of CoCo, not the supporting host side code.
It was kept in arch/x86/kernel because configuring the irq for the PSP through
the ACPI interface requires poking at bits from the architectural vector
domain.

This series is a prerequisite for nested SNP-host support on Hyper-V but is
independent of the SNP-host support patch set. Hyper-V only supports nested
SEV-SNP (not SEV or SEV-ES) so the PSP only supports a subset of the full PSP
command set. Without SNP-host support (which is not upstream yet), the only
PSP command that will succeed is SEV_PLATFORM_STATUS.

Changes since v1:
* move platform_device_add_data() call to commit that introduces psp device
* change psp dependency from CONFIG_AMD_MEM_ENCRYPT to CONFIG_KVM_AMD_SEV
* add blank lines, s/plat/platform/, remove variable initializers before first
  use, remove masking/shifting where not needed
* dynamically allocate sev_vdata/psp_vdata structs instead of overwriting static
  variables

Jeremi Piotrowski (8):
  include/acpi: add definition of ASPT table
  ACPI: ASPT: Add helper to parse table
  x86/psp: Register PSP platform device when ASP table is present
  x86/psp: Add IRQ support
  crypto: cpp - Bind to psp platform device on x86
  crypto: ccp - Add vdata for platform device
  crypto: ccp - Skip DMA coherency check for platform psp
  crypto: ccp - Allow platform device to be psp master device

 arch/x86/kernel/Makefile          |   1 +
 arch/x86/kernel/psp.c             | 219 ++++++++++++++++++++++++++++++
 drivers/acpi/Makefile             |   1 +
 drivers/acpi/aspt.c               | 104 ++++++++++++++
 drivers/crypto/ccp/sp-dev.c       |  66 +++++++++
 drivers/crypto/ccp/sp-dev.h       |   4 +
 drivers/crypto/ccp/sp-pci.c       |  48 -------
 drivers/crypto/ccp/sp-platform.c  |  76 ++++++++++-
 include/acpi/actbl1.h             |  46 +++++++
 include/linux/platform_data/psp.h |  32 +++++
 10 files changed, 548 insertions(+), 49 deletions(-)
 create mode 100644 arch/x86/kernel/psp.c
 create mode 100644 drivers/acpi/aspt.c
 create mode 100644 include/linux/platform_data/psp.h

Comments

Tom Lendacky Feb. 20, 2023, 2:49 p.m. UTC | #1

On 2/13/23 03:24, Jeremi Piotrowski wrote:
> This patch series introduces support for discovering AMD's PSP from an ACPI
> table and extends the CCP driver to allow binding to that device on x86. This
> method of PSP discovery is used on Hyper-V when SNP isolation support is
> exposed to the guest. There is no ACPI node associated with this PSP, so after
> parsing the ASPT it is registered with the system as a platform_device.
> 
> I thought about putting psp.c in arch/x86/coco, but that directory is meant for
> the (confidential) guest side of CoCo, not the supporting host side code.
> It was kept in arch/x86/kernel because configuring the irq for the PSP through
> the ACPI interface requires poking at bits from the architectural vector
> domain.
> 
> This series is a prerequisite for nested SNP-host support on Hyper-V but is
> independent of the SNP-host support patch set. Hyper-V only supports nested
> SEV-SNP (not SEV or SEV-ES) so the PSP only supports a subset of the full PSP
> command set. Without SNP-host support (which is not upstream yet), the only
> PSP command that will succeed is SEV_PLATFORM_STATUS.
> 

For the series:

Acked-by: Tom Lendacky <[e-mail]>

Probably want Boris to weigh in on whether he wants the new psp.c file 
located in arch/x86/kernel, though.

> Changes since v1:
> * move platform_device_add_data() call to commit that introduces psp device
> * change psp dependency from CONFIG_AMD_MEM_ENCRYPT to CONFIG_KVM_AMD_SEV
> * add blank lines, s/plat/platform/, remove variable initializers before first
>    use, remove masking/shifting where not needed
> * dynamically allocate sev_vdata/psp_vdata structs instead of overwriting static
>    variables
> 
> Jeremi Piotrowski (8):
>    include/acpi: add definition of ASPT table
>    ACPI: ASPT: Add helper to parse table
>    x86/psp: Register PSP platform device when ASP table is present
>    x86/psp: Add IRQ support
>    crypto: cpp - Bind to psp platform device on x86
>    crypto: ccp - Add vdata for platform device
>    crypto: ccp - Skip DMA coherency check for platform psp
>    crypto: ccp - Allow platform device to be psp master device
> 
>   arch/x86/kernel/Makefile          |   1 +
>   arch/x86/kernel/psp.c             | 219 ++++++++++++++++++++++++++++++
>   drivers/acpi/Makefile             |   1 +
>   drivers/acpi/aspt.c               | 104 ++++++++++++++
>   drivers/crypto/ccp/sp-dev.c       |  66 +++++++++
>   drivers/crypto/ccp/sp-dev.h       |   4 +
>   drivers/crypto/ccp/sp-pci.c       |  48 -------
>   drivers/crypto/ccp/sp-platform.c  |  76 ++++++++++-
>   include/acpi/actbl1.h             |  46 +++++++
>   include/linux/platform_data/psp.h |  32 +++++
>   10 files changed, 548 insertions(+), 49 deletions(-)
>   create mode 100644 arch/x86/kernel/psp.c
>   create mode 100644 drivers/acpi/aspt.c
>   create mode 100644 include/linux/platform_data/psp.h
>