[tip: x86/urgent] selftests/x86/amx: Update the ARCH_REQ_XCOMP_PERM test

tip-bot2 for Chang S. Bae
2022-03-23T23:31:50Z

The following commit has been merged into the x86/urgent branch of tip:

Commit-ID: 20df737561484cb2d42e537663c03a7311d2b3c1
Gitweb: https://git.kernel.org/tip/20df737561484cb2d42e537663c03a7311d2b3c1
Author: Chang S. Bae <chang.seok.bae@intel.com>
AuthorDate: Sat, 29 Jan 2022 09:36:47 -08:00
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Wed, 23 Mar 2022 21:28:34 +01:00

selftests/x86/amx: Update the ARCH_REQ_XCOMP_PERM test

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>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20220129173647.27981-3-chang.seok.bae@intel.com

---
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 3615ef4..2189f03 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 set a wrong bitmask: %lx, expected: %lx.\n",
+ bitmask, expected_bitmask);
+ } else {
printf("\tARCH_REQ_XCOMP_PERM is successful.\n");
}
}