Commit 0f40caf7 authored by Mark Brown's avatar Mark Brown Committed by Catalin Marinas
Browse files

kselftest/arm64: Add a test for signal frames with ZA disabled 



When ZA is disabled there should be no register data in the ZA signal
frame, add a test case which confirms that this is the case.

Signed-off-by: default avatarMark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220829155728.854947-3-broonie@kernel.org


Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent b95b07d1

tools/testing/selftests/arm64/signal/testcases/za_no_regs.c

0 → 100644
+119 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/*

 * Copyright (C) 2021 ARM Limited

 *

 * Verify that the ZA register context in signal frames is set up as

 * expected.

 */



#include <signal.h>

#include <ucontext.h>

#include <sys/prctl.h>



#include "test_signals_utils.h"

#include "testcases.h"



static union {

	ucontext_t uc;

	char buf[1024 * 128];

} context;

static unsigned int vls[SVE_VQ_MAX];

unsigned int nvls = 0;



static bool sme_get_vls(struct tdescr *td)

{

	int vq, vl;



	/*

	 * Enumerate up to SME_VQ_MAX vector lengths

	 */

	for (vq = SVE_VQ_MAX; vq > 0; --vq) {

		vl = prctl(PR_SME_SET_VL, vq * 16);

		if (vl == -1)

			return false;



		vl &= PR_SME_VL_LEN_MASK;



		/* Skip missing VLs */

		vq = sve_vq_from_vl(vl);



		vls[nvls++] = vl;

	}



	/* We need at least one VL */

	if (nvls < 1) {

		fprintf(stderr, "Only %d VL supported\n", nvls);

		return false;

	}



	return true;

}



static int do_one_sme_vl(struct tdescr *td, siginfo_t *si, ucontext_t *uc,

			 unsigned int vl)

{

	size_t offset;

	struct _aarch64_ctx *head = GET_BUF_RESV_HEAD(context);

	struct za_context *za;



	fprintf(stderr, "Testing VL %d\n", vl);



	if (prctl(PR_SME_SET_VL, vl) != vl) {

		fprintf(stderr, "Failed to set VL\n");

		return 1;

	}



	/*

	 * Get a signal context which should have a SVE frame and registers

	 * in it.

	 */

	if (!get_current_context(td, &context.uc, sizeof(context)))

		return 1;



	head = get_header(head, ZA_MAGIC, GET_BUF_RESV_SIZE(context), &offset);

	if (!head) {

		fprintf(stderr, "No ZA context\n");

		return 1;

	}



	za = (struct za_context *)head;

	if (za->vl != vl) {

		fprintf(stderr, "Got VL %d, expected %d\n", za->vl, vl);

		return 1;

	}



	if (head->size != ZA_SIG_REGS_OFFSET) {

		fprintf(stderr, "Context size %u, expected %lu\n",

			head->size, ZA_SIG_REGS_OFFSET);

		return 1;

	}



	/* The actual size validation is done in get_current_context() */

	fprintf(stderr, "Got expected size %u and VL %d\n",

		head->size, za->vl);



	return 0;

}



static int sme_regs(struct tdescr *td, siginfo_t *si, ucontext_t *uc)

{

	int i;



	for (i = 0; i < nvls; i++) {

		if (do_one_sme_vl(td, si, uc, vls[i]))

			return 1;

	}



	td->pass = 1;



	return 0;

}



struct tdescr tde = {

	.name = "ZA registers - ZA disabled",

	.descr = "Check ZA context with ZA disabled",

	.feats_required = FEAT_SME,

	.timeout = 3,

	.init = sme_get_vls,

	.run = sme_regs,

};