[v9,00/11] Enable writable for idregs DFR0,PFR0, MMFR{0,1,2,3}

Message

Jing Zhang Aug. 21, 2023, 9:22 p.m. UTC

This patch series enable userspace writable for below idregs:
ID_AA64DFR0_EL1, ID_DFR0_EL1, ID_AA64PFR0_EL1, ID_AA64MMFR{0, 1, 2, 3}_EL1.
A vm ioctl is added to get feature ID register writable masks from userspace.
A selftest is added to verify that KVM handles the writings from user space
correctly.
A relevant patch from Oliver is picked from [3].

---

* v8 -> v9
  - Rebase on v6.5-rc7.
  - Don't allow writable on RES0 fields and those fields not exposed by KVM.
  - Fixed build dependency issue for system register definition generation in
    selftest.

* v7 -> v8
  - Rebase on v6.5-rc5.
  - Add reserved parameters to UAPI to get writable masks for future expansion.
  - Import system regiesters definition automatic generation from kernel to
    selftests.
  - Refactor the selftest for verifying ID register writable from userspace to
    cover all writable ID register fields.

* v6 -> v7
  - Rebase on v6.5-rc4.
  - Add a vm ioctl to get feature ID register writable masks from userspace.
  - Split the change for debug version in ID_{AA64}DFR0_EL1.
  - Addressed some bugs in selftest.

* v5 -> v6
  - Override the type of field AA64DFR0_EL1_DebugVer to be FTR_LOWER_SAFE by the
    discussion of Oliver and Suraj.

* v4 -> v5
  - Rebase on v6.5-rc1 which contains infrastructure for writable idregs.
  - Use guest ID registers values for the sake of emulation.
  - Added a selftest to verify idreg userspace writing.

* v3 -> v4
  - Rebase on v11 of writable idregs series at [2].

* v2 -> v3
  - Rebase on v6 of writable idregs series.
  - Enable writable for ID_AA64PFR0_EL1 and ID_AA64MMFR{0, 1, 2}_EL1.

* v1 -> v2
  - Rebase on latest patch series [1] of enabling writable ID register.

[1] https://lore.kernel.org/all/[e-mail]
[2] https://lore.kernel.org/all/[e-mail]
[3] https://lore.kernel.org/kvmarm/[e-mail]

[v1] https://lore.kernel.org/all/[e-mail]
[v2] https://lore.kernel.org/all/[e-mail]
[v3] https://lore.kernel.org/all/[e-mail]
[v4] https://lore.kernel.org/all/[e-mail]
[v5] https://lore.kernel.org/all/[e-mail]
[v6] https://lore.kernel.org/all/[e-mail]
[v7] https://lore.kernel.org/all/[e-mail]
[v8] https://lore.kernel.org/all/[e-mail]

---

Jing Zhang (9):
  KVM: arm64: Allow userspace to get the writable masks for feature ID
    registers
  KVM: arm64: Document KVM_ARM_GET_REG_WRITABLE_MASKS
  KVM: arm64: Use guest ID register values for the sake of emulation
  KVM: arm64: Enable writable for ID_AA64DFR0_EL1 and ID_DFR0_EL1
  KVM: arm64: Enable writable for ID_AA64PFR0_EL1
  KVM: arm64: Refactor helper Macros for idreg desc
  KVM: arm64: Enable writable for ID_AA64MMFR{0, 1, 2, 3}_EL1
  KVM: arm64: selftests: Import automatic system register definition
    generation from kernel
  KVM: arm64: selftests: Test for setting ID register from usersapce

Oliver Upton (2):
  KVM: arm64: Reject attempts to set invalid debug arch version
  KVM: arm64: Bump up the default KVM sanitised debug version to v8p8

 Documentation/virt/kvm/api.rst                |   29 +
 arch/arm64/include/asm/kvm_host.h             |    2 +
 arch/arm64/include/uapi/asm/kvm.h             |   26 +
 arch/arm64/kvm/arm.c                          |    7 +
 arch/arm64/kvm/sys_regs.c                     |  207 +-
 include/uapi/linux/kvm.h                      |    1 +
 tools/arch/arm64/include/.gitignore           |    1 +
 tools/arch/arm64/include/asm/gpr-num.h        |   26 +
 tools/arch/arm64/include/asm/sysreg.h         |  839 ++----
 tools/arch/arm64/tools/gen-sysreg.awk         |  336 +++
 tools/arch/arm64/tools/sysreg                 | 2497 +++++++++++++++++
 tools/testing/selftests/kvm/Makefile          |   15 +-
 .../selftests/kvm/aarch64/aarch32_id_regs.c   |    4 +-
 .../selftests/kvm/aarch64/debug-exceptions.c  |   12 +-
 .../selftests/kvm/aarch64/page_fault_test.c   |    6 +-
 .../selftests/kvm/aarch64/set_id_regs.c       |  448 +++
 .../selftests/kvm/lib/aarch64/processor.c     |    6 +-
 17 files changed, 3739 insertions(+), 723 deletions(-)
 create mode 100644 tools/arch/arm64/include/.gitignore
 create mode 100644 tools/arch/arm64/include/asm/gpr-num.h
 create mode 100755 tools/arch/arm64/tools/gen-sysreg.awk
 create mode 100644 tools/arch/arm64/tools/sysreg
 create mode 100644 tools/testing/selftests/kvm/aarch64/set_id_regs.c


base-commit: 706a741595047797872e669b3101429ab8d378ef

Comments

Cornelia Huck Aug. 23, 2023, 7:37 a.m. UTC | #1

On Mon, Aug 21 2023, Jing Zhang <[e-mail]> wrote:

> This patch series enable userspace writable for below idregs:
> ID_AA64DFR0_EL1, ID_DFR0_EL1, ID_AA64PFR0_EL1, ID_AA64MMFR{0, 1, 2, 3}_EL1.
> A vm ioctl is added to get feature ID register writable masks from userspace.
> A selftest is added to verify that KVM handles the writings from user space
> correctly.
> A relevant patch from Oliver is picked from [3].
>
> ---
>
> * v8 -> v9
>   - Rebase on v6.5-rc7.
>   - Don't allow writable on RES0 fields and those fields not exposed by KVM.
>   - Fixed build dependency issue for system register definition generation in
>     selftest.

What about the changes to the userspace interface as proposed by Marc in
<[e-mail]>?