Update the arch_prctl test to check the permission bitmap whether the requested feature is added as expected or not.

Every non-dynamic feature that is enabled is permitted already for use. TILECFG is not dynamic feature. Ensure the bit is always on from ARCH_GET_XCOMP_PERM.

Signed-off-by: Chang S. Bae chang.seok.bae@intel.com Cc: Dave Hansen dave.hansen@linux.intel.com Cc: linux-kselftest@vger.kernel.org Cc: x86@kernel.org Cc: linux-kernel@vger.kernel.org --- tools/testing/selftests/x86/amx.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/x86/amx.c b/tools/testing/selftests/x86/amx.c index 3615ef4a48bb..e1e2c8f3356f 100644 --- a/tools/testing/selftests/x86/amx.c +++ b/tools/testing/selftests/x86/amx.c @@ -368,9 +368,16 @@ static void req_xtiledata_perm(void)

static void validate_req_xcomp_perm(enum expected_result exp) { - unsigned long bitmask; + unsigned long bitmask, expected_bitmask; long rc;

+ rc = syscall(SYS_arch_prctl, ARCH_GET_XCOMP_PERM, &bitmask); + if (rc) { + fatal_error("prctl(ARCH_GET_XCOMP_PERM) error: %ld", rc); + } else if (!(bitmask & XFEATURE_MASK_XTILECFG)) { + fatal_error("ARCH_GET_XCOMP_PERM returns XFEATURE_XTILECFG off."); + } + rc = syscall(SYS_arch_prctl, ARCH_REQ_XCOMP_PERM, XFEATURE_XTILEDATA); if (exp == FAIL_EXPECTED) { if (rc) { @@ -383,10 +390,15 @@ static void validate_req_xcomp_perm(enum expected_result exp) fatal_error("ARCH_REQ_XCOMP_PERM saw unexpected failure.\n"); }

+ expected_bitmask = bitmask | XFEATURE_MASK_XTILEDATA; + rc = syscall(SYS_arch_prctl, ARCH_GET_XCOMP_PERM, &bitmask); if (rc) { fatal_error("prctl(ARCH_GET_XCOMP_PERM) error: %ld", rc); - } else if (bitmask & XFEATURE_MASK_XTILE) { + } else if (bitmask != expected_bitmask) { + fatal_error("ARCH_REQ_XCOMP_PERM saw a wrong bitmask: %lx, expected: %lx.\n", + bitmask, expected_bitmask); + } else { printf("\tARCH_REQ_XCOMP_PERM is successful.\n"); } }