Merge branch 'for-next/kselftest' into for-next/core

* for-next/kselftest: (28 commits)
  : Kselftest updates for arm64
  kselftest/arm64: Handle EINTR while reading data from children
  kselftest/arm64: Flag fp-stress as exiting when we begin finishing up
  kselftest/arm64: Don't repeat termination handler for fp-stress
  kselftest/arm64: Don't enable v8.5 for MTE selftest builds
  kselftest/arm64: Fix typo in hwcap check
  kselftest/arm64: Add hwcap test for RNG
  kselftest/arm64: Add SVE 2 to the tested hwcaps
  kselftest/arm64: Add missing newline in hwcap output
  kselftest/arm64: Fix spelling misakes of signal names
  kselftest/arm64: Enforce actual ABI for SVE syscalls
  kselftest/arm64: Correct buffer allocation for SVE Z registers
  kselftest/arm64: Include larger SVE and SME VLs in signal tests
  kselftest/arm64: Allow larger buffers in get_signal_context()
  kselftest/arm64: Preserve any EXTRA_CONTEXT in handle_signal_copyctx()
  kselftest/arm64: Validate contents of EXTRA_CONTEXT blocks
  kselftest/arm64: Only validate each signal context once
  kselftest/arm64: Remove unneeded protype for validate_extra_context()
  kselftest/arm64: Fix validation of EXTRA_CONTEXT signal context location
  kselftest/arm64: Fix validatation termination record after EXTRA_CONTEXT
  kselftest/arm64: Validate signal ucontext in place
  ...

Author: ctmarinas

tools/testing/selftests/arm64/abi/.gitignore

@@ -1,3 +1,4 @@
+hwcap
 ptrace
 syscall-abi
 tpidr2

tools/testing/selftests/arm64/abi/Makefile

@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 # Copyright (C) 2021 ARM Limited
 
-TEST_GEN_PROGS := ptrace syscall-abi tpidr2
+TEST_GEN_PROGS := hwcap ptrace syscall-abi tpidr2
 
 include ../../lib.mk
 

tools/testing/selftests/arm64/abi/hwcap.c

@@ -0,0 +1,336 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2022 ARM Limited.
+ */
+
+#include <errno.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/auxv.h>
+#include <sys/prctl.h>
+#include <asm/hwcap.h>
+#include <asm/sigcontext.h>
+#include <asm/unistd.h>
+
+#include "../../kselftest.h"
+
+#define TESTS_PER_HWCAP 2
+
+/*
+ * Function expected to generate SIGILL when the feature is not
+ * supported and return when it is supported. If SIGILL is generated
+ * then the handler must be able to skip over the instruction safely.
+ *
+ * Note that it is expected that for many architecture extensions
+ * there are no specific traps due to no architecture state being
+ * added so we may not fault if running on a kernel which doesn't know
+ * to add the hwcap.
+ */
+typedef void (*sigill_fn)(void);
+
+static void rng_sigill(void)
+{
+	asm volatile("mrs x0, S3_3_C2_C4_0" : : : "x0");
+}
+
+static void sme_sigill(void)
+{
+	/* RDSVL x0, #0 */
+	asm volatile(".inst 0x04bf5800" : : : "x0");
+}
+
+static void sve_sigill(void)
+{
+	/* RDVL x0, #0 */
+	asm volatile(".inst 0x04bf5000" : : : "x0");
+}
+
+static void sve2_sigill(void)
+{
+	/* SQABS Z0.b, P0/M, Z0.B */
+	asm volatile(".inst 0x4408A000" : : : "z0");
+}
+
+static void sveaes_sigill(void)
+{
+	/* AESD z0.b, z0.b, z0.b */
+	asm volatile(".inst 0x4522e400" : : : "z0");
+}
+
+static void svepmull_sigill(void)
+{
+	/* PMULLB Z0.Q, Z0.D, Z0.D */
+	asm volatile(".inst 0x45006800" : : : "z0");
+}
+
+static void svebitperm_sigill(void)
+{
+	/* BDEP Z0.B, Z0.B, Z0.B */
+	asm volatile(".inst 0x4500b400" : : : "z0");
+}
+
+static void svesha3_sigill(void)
+{
+	/* EOR3 Z0.D, Z0.D, Z0.D, Z0.D */
+	asm volatile(".inst 0x4203800" : : : "z0");
+}
+
+static void svesm4_sigill(void)
+{
+	/* SM4E Z0.S, Z0.S, Z0.S */
+	asm volatile(".inst 0x4523e000" : : : "z0");
+}
+
+static void svei8mm_sigill(void)
+{
+	/* USDOT Z0.S, Z0.B, Z0.B[0] */
+	asm volatile(".inst 0x44a01800" : : : "z0");
+}
+
+static void svef32mm_sigill(void)
+{
+	/* FMMLA Z0.S, Z0.S, Z0.S */
+	asm volatile(".inst 0x64a0e400" : : : "z0");
+}
+
+static void svef64mm_sigill(void)
+{
+	/* FMMLA Z0.D, Z0.D, Z0.D */
+	asm volatile(".inst 0x64e0e400" : : : "z0");
+}
+
+static void svebf16_sigill(void)
+{
+	/* BFCVT Z0.H, P0/M, Z0.S */
+	asm volatile(".inst 0x658aa000" : : : "z0");
+}
+
+static const struct hwcap_data {
+	const char *name;
+	unsigned long at_hwcap;
+	unsigned long hwcap_bit;
+	const char *cpuinfo;
+	sigill_fn sigill_fn;
+	bool sigill_reliable;
+} hwcaps[] = {
+	{
+		.name = "RNG",
+		.at_hwcap = AT_HWCAP2,
+		.hwcap_bit = HWCAP2_RNG,
+		.cpuinfo = "rng",
+		.sigill_fn = rng_sigill,
+	},
+	{
+		.name = "SME",
+		.at_hwcap = AT_HWCAP2,
+		.hwcap_bit = HWCAP2_SME,
+		.cpuinfo = "sme",
+		.sigill_fn = sme_sigill,
+		.sigill_reliable = true,
+	},
+	{
+		.name = "SVE",
+		.at_hwcap = AT_HWCAP,
+		.hwcap_bit = HWCAP_SVE,
+		.cpuinfo = "sve",
+		.sigill_fn = sve_sigill,
+		.sigill_reliable = true,
+	},
+	{
+		.name = "SVE 2",
+		.at_hwcap = AT_HWCAP2,
+		.hwcap_bit = HWCAP2_SVE2,
+		.cpuinfo = "sve2",
+		.sigill_fn = sve2_sigill,
+	},
+	{
+		.name = "SVE AES",
+		.at_hwcap = AT_HWCAP2,
+		.hwcap_bit = HWCAP2_SVEAES,
+		.cpuinfo = "sveaes",
+		.sigill_fn = sveaes_sigill,
+	},
+	{
+		.name = "SVE2 PMULL",
+		.at_hwcap = AT_HWCAP2,
+		.hwcap_bit = HWCAP2_SVEPMULL,
+		.cpuinfo = "svepmull",
+		.sigill_fn = svepmull_sigill,
+	},
+	{
+		.name = "SVE2 BITPERM",
+		.at_hwcap = AT_HWCAP2,
+		.hwcap_bit = HWCAP2_SVEBITPERM,
+		.cpuinfo = "svebitperm",
+		.sigill_fn = svebitperm_sigill,
+	},
+	{
+		.name = "SVE2 SHA3",
+		.at_hwcap = AT_HWCAP2,
+		.hwcap_bit = HWCAP2_SVESHA3,
+		.cpuinfo = "svesha3",
+		.sigill_fn = svesha3_sigill,
+	},
+	{
+		.name = "SVE2 SM4",
+		.at_hwcap = AT_HWCAP2,
+		.hwcap_bit = HWCAP2_SVESM4,
+		.cpuinfo = "svesm4",
+		.sigill_fn = svesm4_sigill,
+	},
+	{
+		.name = "SVE2 I8MM",
+		.at_hwcap = AT_HWCAP2,
+		.hwcap_bit = HWCAP2_SVEI8MM,
+		.cpuinfo = "svei8mm",
+		.sigill_fn = svei8mm_sigill,
+	},
+	{
+		.name = "SVE2 F32MM",
+		.at_hwcap = AT_HWCAP2,
+		.hwcap_bit = HWCAP2_SVEF32MM,
+		.cpuinfo = "svef32mm",
+		.sigill_fn = svef32mm_sigill,
+	},
+	{
+		.name = "SVE2 F64MM",
+		.at_hwcap = AT_HWCAP2,
+		.hwcap_bit = HWCAP2_SVEF64MM,
+		.cpuinfo = "svef64mm",
+		.sigill_fn = svef64mm_sigill,
+	},
+	{
+		.name = "SVE2 BF16",
+		.at_hwcap = AT_HWCAP2,
+		.hwcap_bit = HWCAP2_SVEBF16,
+		.cpuinfo = "svebf16",
+		.sigill_fn = svebf16_sigill,
+	},
+	{
+		.name = "SVE2 EBF16",
+		.at_hwcap = AT_HWCAP2,
+		.hwcap_bit = HWCAP2_SVE_EBF16,
+		.cpuinfo = "sveebf16",
+	},
+};
+
+static bool seen_sigill;
+
+static void handle_sigill(int sig, siginfo_t *info, void *context)
+{
+	ucontext_t *uc = context;
+
+	seen_sigill = true;
+
+	/* Skip over the offending instruction */
+	uc->uc_mcontext.pc += 4;
+}
+
+bool cpuinfo_present(const char *name)
+{
+	FILE *f;
+	char buf[2048], name_space[30], name_newline[30];
+	char *s;
+
+	/*
+	 * The feature should appear with a leading space and either a
+	 * trailing space or a newline.
+	 */
+	snprintf(name_space, sizeof(name_space), " %s ", name);
+	snprintf(name_newline, sizeof(name_newline), " %s\n", name);
+
+	f = fopen("/proc/cpuinfo", "r");
+	if (!f) {
+		ksft_print_msg("Failed to open /proc/cpuinfo\n");
+		return false;
+	}
+
+	while (fgets(buf, sizeof(buf), f)) {
+		/* Features: line? */
+		if (strncmp(buf, "Features\t:", strlen("Features\t:")) != 0)
+			continue;
+
+		/* All CPUs should be symmetric, don't read any more */
+		fclose(f);
+
+		s = strstr(buf, name_space);
+		if (s)
+			return true;
+		s = strstr(buf, name_newline);
+		if (s)
+			return true;
+
+		return false;
+	}
+
+	ksft_print_msg("Failed to find Features in /proc/cpuinfo\n");
+	fclose(f);
+	return false;
+}
+
+int main(void)
+{
+	const struct hwcap_data *hwcap;
+	int i, ret;
+	bool have_cpuinfo, have_hwcap;
+	struct sigaction sa;
+
+	ksft_print_header();
+	ksft_set_plan(ARRAY_SIZE(hwcaps) * TESTS_PER_HWCAP);
+
+	memset(&sa, 0, sizeof(sa));
+	sa.sa_sigaction = handle_sigill;
+	sa.sa_flags = SA_RESTART | SA_SIGINFO;
+	sigemptyset(&sa.sa_mask);
+	ret = sigaction(SIGILL, &sa, NULL);
+	if (ret < 0)
+		ksft_exit_fail_msg("Failed to install SIGILL handler: %s (%d)\n",
+				   strerror(errno), errno);
+
+	for (i = 0; i < ARRAY_SIZE(hwcaps); i++) {
+		hwcap = &hwcaps[i];
+
+		have_hwcap = getauxval(hwcap->at_hwcap) & hwcap->hwcap_bit;
+		have_cpuinfo = cpuinfo_present(hwcap->cpuinfo);
+
+		if (have_hwcap)
+			ksft_print_msg("%s present\n", hwcap->name);
+
+		ksft_test_result(have_hwcap == have_cpuinfo,
+				 "cpuinfo_match_%s\n", hwcap->name);
+
+		if (hwcap->sigill_fn) {
+			seen_sigill = false;
+			hwcap->sigill_fn();
+
+			if (have_hwcap) {
+				/* Should be able to use the extension */
+				ksft_test_result(!seen_sigill, "sigill_%s\n",
+						 hwcap->name);
+			} else if (hwcap->sigill_reliable) {
+				/* Guaranteed a SIGILL */
+				ksft_test_result(seen_sigill, "sigill_%s\n",
+						 hwcap->name);
+			} else {
+				/* Missing SIGILL might be fine */
+				ksft_print_msg("SIGILL %sreported for %s\n",
+					       seen_sigill ? "" : "not ",
+					       hwcap->name);
+				ksft_test_result_skip("sigill_%s\n",
+						      hwcap->name);
+			}
+		} else {
+			ksft_test_result_skip("sigill_%s\n",
+					      hwcap->name);
+		}
+	}
+
+	ksft_print_cnts();
+
+	return 0;
+}