In order to allow exiting streaming mode on systems with SME but not SVE we allow writes of FPSIMD format data via NT_ARM_SVE even when SVE is not supported, add a test case that covers this to sve-ptrace.
We do not support reads.
Signed-off-by: Mark Brown broonie@kernel.org --- tools/testing/selftests/arm64/fp/sve-ptrace.c | 61 +++++++++++++++++++++++++++ 1 file changed, 61 insertions(+)
diff --git a/tools/testing/selftests/arm64/fp/sve-ptrace.c b/tools/testing/selftests/arm64/fp/sve-ptrace.c index e0fc3a001e28..f44d44618575 100644 --- a/tools/testing/selftests/arm64/fp/sve-ptrace.c +++ b/tools/testing/selftests/arm64/fp/sve-ptrace.c @@ -394,6 +394,58 @@ static void ptrace_sve_fpsimd(pid_t child, const struct vec_type *type) free(svebuf); }
+/* Write the FPSIMD registers via the SVE regset when SVE is not supported */ +static void ptrace_sve_fpsimd_no_sve(pid_t child) +{ + void *svebuf; + struct user_sve_header *sve; + struct user_fpsimd_state *fpsimd, new_fpsimd; + unsigned int i, j; + unsigned char *p; + int ret; + + svebuf = malloc(SVE_PT_SIZE(0, SVE_PT_REGS_FPSIMD)); + if (!svebuf) { + ksft_test_result_fail("Failed to allocate FPSIMD buffer\n"); + return; + } + + /* On a system without SVE the VL should be set to 0 */ + memset(svebuf, 0, SVE_PT_SIZE(0, SVE_PT_REGS_FPSIMD)); + sve = svebuf; + sve->flags = SVE_PT_REGS_FPSIMD; + sve->size = SVE_PT_SIZE(0, SVE_PT_REGS_FPSIMD); + sve->vl = 0; + + /* Try to set a known FPSIMD state via PT_REGS_SVE */ + fpsimd = (struct user_fpsimd_state *)((char *)sve + + SVE_PT_FPSIMD_OFFSET); + for (i = 0; i < 32; ++i) { + p = (unsigned char *)&fpsimd->vregs[i]; + + for (j = 0; j < sizeof(fpsimd->vregs[i]); ++j) + p[j] = j; + } + + ret = set_sve(child, &vec_types[0], sve); + ksft_test_result(ret == 0, "FPSIMD write via SVE\n"); + if (ret) { + ksft_test_result_skip("Verify FPSIMD write via SVE\n"); + goto out; + } + + /* Verify via the FPSIMD regset */ + if (get_fpsimd(child, &new_fpsimd)) { + ksft_test_result_skip("Verify FPSIMD write via SVE\n"); + goto out; + } + ksft_test_result(memcmp(fpsimd, &new_fpsimd, sizeof(*fpsimd)) == 0, + "Verify FPSIMD write via SVE\n"); + +out: + free(svebuf); +} + /* Validate attempting to set SVE data and read SVE data */ static void ptrace_set_sve_get_sve_data(pid_t child, const struct vec_type *type, @@ -826,6 +878,15 @@ static int do_parent(pid_t child) } }
+ /* We support SVE writes of FPSMID format on SME only systems */ + if (!(getauxval(AT_HWCAP) & HWCAP_SVE) && + (getauxval(AT_HWCAP2) & HWCAP2_SME)) { + ptrace_sve_fpsimd_no_sve(child); + } else { + ksft_test_result_skip("FPSIMD write via SVE\n"); + ksft_test_result_skip("Verify FPSIMD write via SVE\n"); + } + ret = EXIT_SUCCESS;
error: