[RFC v3 00/10] KVM: selftests: add powerpc support

From: Ritesh Harjani (IBM)

Date: Wed May 27 2026 - 08:54:20 EST


Hi All,

This series primarly adds KVM selftests support for powerpc (64-bit, BookS,
radix MMU).

This patch series is originally Nick's work. I have mainly only rebased it on
the latest upstream tree. Since the rebase required few changes to all the four
patches (Patch 1-4), I have dropped the earlier Acked-by from Michael Ellerman.

Since the last series was posted three years ago [1], I am resetting the version
to RFC. This rebase was done as part of a larger effort to improve the selftests
infrastructure for Linux on PowerPC tree. Thanks to Harsh and Maddy for their
help on this.


Testing Updates:
================
1. Tested this on PowerNV P9 with Radix mode. (all selftests passes)
2. Tested this on LPAR (KVM on PowerVM) case. (all selftests except-1 passes).
The failed testcase (kvm_create_max_vcpus) is because H_GUEST_CREATE_VCPU
(PAPR HCALL) only supports vcpu_ids 0-2047 i.e. max 2048 vcpus.
However, kernel always returns NR_CPUS for the KVM_CAP_MAX_VCPUS extension.
So if the LPAR kernel is built using NR_CPUS=8192, then kvm_create_max_vcpus
can fail in __vm_vcpu_add(). This failure needs to be handled separately,
mostly as fix in kernel.
3. Tested these selftests changes inside x86 kvm guest - no new failures seen.


RFCv2 -> RFC v3:
===============
1. Relaxed strict pte permission checking in patch-3 (Sashiko)
2. Fixed errno from getting clobbered in patch-5 (Sashiko)
3. Added PATCH 6-9 to handle the type conversion (e.g. uint64_t to u64) as was
done earlier with other kvm selftests. Kept these patches separate to keep
the review & changelog simpler.
4. Added PATCH 10, which replaces u64 gpa/gva to use gpa_t and gva_t and
converts the vaddr variable to gva as done by some previous commits for other
kvm selftests. Kept this patch separate to keep the review & changelog
simpler.


RFC v1 -> RFC v2
================
(mostly Sashiko review comments)
1. Fixed x86's stage-2 mmu handling in patch-1 - commit msg has more description
2. Added "cc" into the clobber list for hcalls in patch-3
3. Fixed the size calculation in kvm_arch_vm_post_create in patch-3 for
allocating 2 pages for 4K pagesize
4. Added patch-5 which prints vcpu_id in case of an error

[RFCv2]: https://lore.kernel.org/all/cover.1779524962.git.ritesh.list@xxxxxxxxx/
[RFCv1]: https://lore.kernel.org/linuxppc-dev/cover.1778857539.git.ritesh.list@xxxxxxxxx/
[1]: https://lore.kernel.org/all/20231120122920.293076-1-npiggin@xxxxxxxxx/


Nicholas Piggin (4):
KVM: selftests: Move pgd_created check into virt_pgd_alloc
KVM: selftests: Add aligned guest physical page allocator
KVM: PPC: selftests: add support for powerpc
KVM: PPC: selftests: powerpc enable kvm_create_max_vcpus test

Ritesh Harjani (IBM) (6):
KVM: selftests: Print the vcpu_id when KVM_CREATE_VCPU ioctl fails
KVM: PPC: selftests: Use u64 instead of uint64_t
KVM: PPC: selftests: Use s64 instead of int64_t
KVM: PPC: selftests: Use u32 instead of uint32_t
KVM: PPC: selftests: Use u8 instead of uint8_t
KVM: PPC: selftests: Replace u64 gpa, u64 gva|vaddr with gpa_t and gva_t

MAINTAINERS | 2 +
tools/testing/selftests/kvm/Makefile | 2 +-
tools/testing/selftests/kvm/Makefile.kvm | 10 +
.../testing/selftests/kvm/include/kvm_util.h | 34 +-
.../selftests/kvm/include/powerpc/hcall.h | 17 +
.../kvm/include/powerpc/kvm_util_arch.h | 22 +
.../selftests/kvm/include/powerpc/ppc_asm.h | 32 ++
.../selftests/kvm/include/powerpc/processor.h | 39 ++
.../selftests/kvm/include/powerpc/ucall.h | 21 +
.../selftests/kvm/kvm_create_max_vcpus.c | 9 +
.../selftests/kvm/lib/arm64/processor.c | 4 -
tools/testing/selftests/kvm/lib/guest_modes.c | 20 +-
tools/testing/selftests/kvm/lib/kvm_util.c | 48 +-
.../selftests/kvm/lib/loongarch/processor.c | 4 -
.../selftests/kvm/lib/powerpc/handlers.S | 93 ++++
.../testing/selftests/kvm/lib/powerpc/hcall.c | 45 ++
.../selftests/kvm/lib/powerpc/processor.c | 483 ++++++++++++++++++
.../testing/selftests/kvm/lib/powerpc/ucall.c | 22 +
.../selftests/kvm/lib/riscv/processor.c | 4 -
.../selftests/kvm/lib/s390/processor.c | 4 -
20 files changed, 876 insertions(+), 39 deletions(-)
create mode 100644 tools/testing/selftests/kvm/include/powerpc/hcall.h
create mode 100644 tools/testing/selftests/kvm/include/powerpc/kvm_util_arch.h
create mode 100644 tools/testing/selftests/kvm/include/powerpc/ppc_asm.h
create mode 100644 tools/testing/selftests/kvm/include/powerpc/processor.h
create mode 100644 tools/testing/selftests/kvm/include/powerpc/ucall.h
create mode 100644 tools/testing/selftests/kvm/lib/powerpc/handlers.S
create mode 100644 tools/testing/selftests/kvm/lib/powerpc/hcall.c
create mode 100644 tools/testing/selftests/kvm/lib/powerpc/processor.c
create mode 100644 tools/testing/selftests/kvm/lib/powerpc/ucall.c

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2.39.5