Add RISC-V KVM selftests to verify the SBI Steal-Time Accounting (STA) shared memory alignment requirements.
The SBI specification requires the STA shared memory GPA to be 64-byte aligned, or set to all-ones to explicitly disable steal-time accounting. This test verifies that KVM enforces the expected behavior when configuring the SBI STA shared memory via KVM_SET_ONE_REG. Specifically, the test checks that: - misaligned GPAs are rejected with -EINVAL - 64-byte aligned GPAs are accepted - all-ones GPA is accepted Signed-off-by: Jiakai Xu <[email protected]> Signed-off-by: Jiakai Xu <[email protected]> --- V6 -> V7: - Removed RISCV_SBI_STA_REG() macro addition and used existing KVM_REG_RISCV_SBI_STA_REG(shmem_lo) instead. - Refined assertion messages per review feedback. - Split into two patches per Andrew Jones' suggestion: Refactored UAPI tests from steal_time_init() into dedicated check_steal_time_uapi() function and added empty stub for RISC-V. Filled in RISC-V stub with STA alignment tests. (this patch) --- tools/testing/selftests/kvm/steal_time.c | 26 +++++++++++++++++++++++- 1 file changed, 25 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/kvm/steal_time.c b/tools/testing/selftests/kvm/steal_time.c index a814f6f3f8b41..2af7fd7513d55 100644 --- a/tools/testing/selftests/kvm/steal_time.c +++ b/tools/testing/selftests/kvm/steal_time.c @@ -233,6 +233,7 @@ static void check_steal_time_uapi(struct kvm_vcpu *vcpu) /* SBI STA shmem must have 64-byte alignment */ #define STEAL_TIME_SIZE ((sizeof(struct sta_struct) + 63) & ~63) +#define INVALID_GPA (~(u64)0) static vm_paddr_t st_gpa[NR_VCPUS]; @@ -327,7 +328,30 @@ static void steal_time_dump(struct kvm_vm *vm, uint32_t vcpu_idx) static void check_steal_time_uapi(struct kvm_vcpu *vcpu) { - /* RISC-V UAPI tests will be added in a subsequent patch */ + struct kvm_one_reg reg; + uint64_t shmem; + int ret; + + reg.id = KVM_REG_RISCV_SBI_STA_REG(shmem_lo); + reg.addr = (uint64_t)&shmem; + + /* Case 1: misaligned GPA */ + shmem = ST_GPA_BASE + 1; + ret = __vcpu_ioctl(vcpu, KVM_SET_ONE_REG, ®); + TEST_ASSERT(ret == -1 && errno == EINVAL, + "misaligned STA shmem returns -EINVAL"); + + /* Case 2: 64-byte aligned GPA */ + shmem = ST_GPA_BASE; + ret = __vcpu_ioctl(vcpu, KVM_SET_ONE_REG, ®); + TEST_ASSERT(ret == 0, + "aligned STA shmem succeeds"); + + /* Case 3: INVALID_GPA disables STA */ + shmem = INVALID_GPA; + ret = __vcpu_ioctl(vcpu, KVM_SET_ONE_REG, ®); + TEST_ASSERT(ret == 0, + "all-ones for STA shmem succeeds"); } #endif -- 2.34.1
