selftests: arm64: SVE ptrace test rework

index 612d3899614a..7f7ed1c96867 100644
@@ -19,6 +19,8 @@
 
 #include "../../kselftest.h"
 
+#define EXPECTED_TESTS 20
+
 /* <linux/elf.h> and <sys/auxv.h> don't like each other, so: */
 #ifndef NT_ARM_SVE
 #define NT_ARM_SVE 0x405

@@ -313,7 +315,7 @@ int main(void)
 	pid_t child;
 
 	ksft_print_header();
-	ksft_set_plan(20);
+	ksft_set_plan(EXPECTED_TESTS);
 
 	if (!(getauxval(AT_HWCAP) & HWCAP_SVE))
 		ksft_exit_skip("SVE not available\n");

index 7f7ed1c96867..7035f01423b3 100644
@@ -19,7 +19,7 @@
 
 #include "../../kselftest.h"
 
-#define EXPECTED_TESTS 20
+#define EXPECTED_TESTS 19
 
 /* <linux/elf.h> and <sys/auxv.h> don't like each other, so: */
 #ifndef NT_ARM_SVE

@@ -169,8 +169,6 @@ static int do_parent(pid_t child)
 		if (WIFEXITED(status) || WIFSIGNALED(status))
 			ksft_exit_fail_msg("Child died unexpectedly\n");
 
-		ksft_test_result(WIFSTOPPED(status), "WIFSTOPPED(%d)\n",
-				 status);
 		if (!WIFSTOPPED(status))
 			goto error;
 

index 7035f01423b3..d2ec48f649f9 100644
@@ -26,11 +26,6 @@
 #define NT_ARM_SVE 0x405
 #endif
 
-/* Number of registers filled in by sve_store_patterns */
-#define NR_VREGS 5
-
-void sve_store_patterns(__uint128_t v[NR_VREGS]);
-
 static void dump(const void *buf, size_t size)
 {
 	size_t i;

@@ -40,23 +35,6 @@ static void dump(const void *buf, size_t size)
 		printf(" %.2x", *p++);
 }
 
-static int check_vregs(const __uint128_t vregs[NR_VREGS])
-{
-	int i;
-	int ok = 1;
-
-	for (i = 0; i < NR_VREGS; ++i) {
-		printf("# v[%d]:", i);
-		dump(&vregs[i], sizeof vregs[i]);
-		putchar('\n');
-
-		if (vregs[i] != vregs[0])
-			ok = 0;
-	}
-
-	return ok;
-}
-
 static int do_child(void)
 {
 	if (ptrace(PTRACE_TRACEME, -1, NULL, NULL))

@@ -309,7 +287,6 @@ static int do_parent(pid_t child)
 int main(void)
 {
 	int ret = EXIT_SUCCESS;
-	__uint128_t v[NR_VREGS];
 	pid_t child;
 
 	ksft_print_header();

@@ -318,11 +295,6 @@ int main(void)
 	if (!(getauxval(AT_HWCAP) & HWCAP_SVE))
 		ksft_exit_skip("SVE not available\n");
 
-	sve_store_patterns(v);
-
-	if (!check_vregs(v))
-		ksft_exit_fail_msg("Initial check_vregs() failed\n");
-
 	child = fork();
 	if (!child)
 		return do_child();

index d2ec48f649f9..fc4a672825eb 100644
@@ -181,6 +181,7 @@ static int do_parent(pid_t child)
 		}
 	}
 
+	/* New process should start with FPSIMD registers only */
 	sve = get_sve(pid, &svebuf, &svebufsz);
 	if (!sve) {
 		int e = errno;

@@ -191,14 +192,15 @@ static int do_parent(pid_t child)
 
 		goto error;
 	} else {
-		ksft_test_result_pass("get_sve\n");
+		ksft_test_result_pass("get_sve(FPSIMD)\n");
 	}
 
 	ksft_test_result((sve->flags & SVE_PT_REGS_MASK) == SVE_PT_REGS_FPSIMD,
-			 "FPSIMD registers\n");
+			 "Set FPSIMD registers\n");
 	if ((sve->flags & SVE_PT_REGS_MASK) != SVE_PT_REGS_FPSIMD)
 		goto error;
 
+	/* 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) {

@@ -219,6 +221,7 @@ static int do_parent(pid_t child)
 		goto error;
 	}
 
+	/* Zero the first SVE Z register */
 	vq = sve_vq_from_vl(sve->vl);
 
 	newsvebufsz = SVE_PT_SVE_ZREG_OFFSET(vq, 1);

@@ -245,6 +248,7 @@ static int do_parent(pid_t child)
 		goto error;
 	}
 
+	/* Try to read back the value we just set */
 	new_sve = get_sve(pid, &newsvebuf, &newsvebufsz);
 	if (!new_sve) {
 		int e = errno;

@@ -257,12 +261,13 @@ static int do_parent(pid_t child)
 	}
 
 	ksft_test_result((new_sve->flags & SVE_PT_REGS_MASK) == SVE_PT_REGS_SVE,
-			 "SVE registers\n");
+			 "Get SVE registers\n");
 	if ((new_sve->flags & SVE_PT_REGS_MASK) != SVE_PT_REGS_SVE)
 		goto error;
 
 	dump_sve_regs(new_sve, 3, sizeof fpsimd->vregs[0]);
 
+	/* Verify that the register we set has the value we expected */
 	p = (unsigned char *)new_sve + SVE_PT_SVE_ZREG_OFFSET(vq, 1);
 	for (i = 0; i < sizeof fpsimd->vregs[0]; ++i) {
 		unsigned char expected = i;

index fc4a672825eb..2d130fedc019 100644
@@ -275,7 +275,7 @@ static int do_parent(pid_t child)
 		if (__BYTE_ORDER == __BIG_ENDIAN)
 			expected = sizeof fpsimd->vregs[0] - 1 - expected;
 
-		ksft_test_result(p[i] == expected, "p[%d] == expected\n", i);
+		ksft_test_result(p[i] == expected, "buf[%d] == expected\n", i);
 		if (p[i] != expected)
 			goto error;
 	}

index 2d130fedc019..31a2c2fc529d 100644
@@ -46,6 +46,15 @@ static int do_child(void)
 	return EXIT_SUCCESS;
 }
 
+static int get_fpsimd(pid_t pid, struct user_fpsimd_state *fpsimd)
+{
+	struct iovec iov;
+
+	iov.iov_base = fpsimd;
+	iov.iov_len = sizeof(*fpsimd);
+	return ptrace(PTRACE_GETREGSET, pid, NT_PRFPREG, &iov);
+}
+
 static struct user_sve_header *get_sve(pid_t pid, void **buf, size_t *size)
 {
 	struct user_sve_header *sve;

@@ -122,7 +131,7 @@ static int do_parent(pid_t child)
 	void *svebuf = NULL, *newsvebuf;
 	size_t svebufsz = 0, newsvebufsz;
 	struct user_sve_header *sve, *new_sve;
-	struct user_fpsimd_state *fpsimd;
+	struct user_fpsimd_state *fpsimd, new_fpsimd;
 	unsigned int i, j;
 	unsigned char *p;
 	unsigned int vq;

@@ -221,7 +230,22 @@ static int do_parent(pid_t child)
 		goto error;
 	}
 
-	/* Zero the first SVE Z register */
+	/* Verify via the FPSIMD regset */
+	if (get_fpsimd(pid, &new_fpsimd)) {
+		int e = errno;
+
+		ksft_test_result_fail("get_fpsimd(): %s\n",
+				      strerror(errno));
+		if (e == ESRCH)
+			goto disappeared;
+
+		goto error;
+	}
+	if (memcmp(fpsimd, &new_fpsimd, sizeof(*fpsimd)) == 0)
+		ksft_test_result_pass("get_fpsimd() gave same state\n");
+	else
+		ksft_test_result_fail("get_fpsimd() gave different state\n");
+
 	vq = sve_vq_from_vl(sve->vl);
 
 	newsvebufsz = SVE_PT_SVE_ZREG_OFFSET(vq, 1);

389 lines not on this page · raw message

index 199710ba65c7..ac0629f05365 100644
@@ -158,6 +158,63 @@ static void check_u32(unsigned int vl, const char *reg,
 	}
 }
 
+/* Access the FPSIMD registers via the SVE regset */
+static void ptrace_sve_fpsimd(pid_t child)
+{
+	void *svebuf = NULL;
+	size_t svebufsz = 0;
+	struct user_sve_header *sve;
+	struct user_fpsimd_state *fpsimd, new_fpsimd;
+	unsigned int i, j;
+	unsigned char *p;
+
+	/* New process should start with FPSIMD registers only */
+	sve = get_sve(child, &svebuf, &svebufsz);
+	if (!sve) {
+		ksft_test_result_fail("get_sve: %s\n", strerror(errno));
+
+		return;
+	} else {
+		ksft_test_result_pass("get_sve(FPSIMD)\n");
+	}
+
+	ksft_test_result((sve->flags & SVE_PT_REGS_MASK) == SVE_PT_REGS_FPSIMD,
+			 "Set FPSIMD registers\n");
+	if ((sve->flags & SVE_PT_REGS_MASK) != SVE_PT_REGS_FPSIMD)
+		goto out;
+
+	/* 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;
+	}
+
+	if (set_sve(child, sve)) {
+		ksft_test_result_fail("set_sve(FPSIMD): %s\n",
+				      strerror(errno));
+
+		goto out;
+	}
+
+	/* Verify via the FPSIMD regset */
+	if (get_fpsimd(child, &new_fpsimd)) {
+		ksft_test_result_fail("get_fpsimd(): %s\n",
+				      strerror(errno));
+		goto out;
+	}
+	if (memcmp(fpsimd, &new_fpsimd, sizeof(*fpsimd)) == 0)
+		ksft_test_result_pass("get_fpsimd() gave same state\n");
+	else
+		ksft_test_result_fail("get_fpsimd() gave different state\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, unsigned int vl)
 {

@@ -335,12 +392,6 @@ static int do_parent(pid_t child)
 	pid_t pid;
 	int status;
 	siginfo_t si;
-	void *svebuf = NULL;
-	size_t svebufsz = 0;
-	struct user_sve_header *sve;
-	struct user_fpsimd_state *fpsimd, new_fpsimd;
-	unsigned int i, j;
-	unsigned char *p;
 	unsigned int vq, vl;
 	bool vl_supported;
 

@@ -398,61 +449,8 @@ static int do_parent(pid_t child)
 		}
 	}
 
-	/* New process should start with FPSIMD registers only */
-	sve = get_sve(pid, &svebuf, &svebufsz);
-	if (!sve) {
-		int e = errno;
-
-		ksft_test_result_fail("get_sve: %s\n", strerror(errno));
-		if (e == ESRCH)
-			goto disappeared;
-
-		goto error;
-	} else {
-		ksft_test_result_pass("get_sve(FPSIMD)\n");
-	}
-
-	ksft_test_result((sve->flags & SVE_PT_REGS_MASK) == SVE_PT_REGS_FPSIMD,
-			 "Set FPSIMD registers\n");
-	if ((sve->flags & SVE_PT_REGS_MASK) != SVE_PT_REGS_FPSIMD)
-		goto error;
-
-	/* 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;
-	}
-
-	if (set_sve(pid, sve)) {
-		int e = errno;
-
-		ksft_test_result_fail("set_sve(FPSIMD): %s\n",
-				      strerror(errno));
-		if (e == ESRCH)
-			goto disappeared;
-
-		goto error;
-	}
-
-	/* Verify via the FPSIMD regset */
-	if (get_fpsimd(pid, &new_fpsimd)) {
-		int e = errno;
-
-		ksft_test_result_fail("get_fpsimd(): %s\n",
-				      strerror(errno));
-		if (e == ESRCH)
-			goto disappeared;
-
-		goto error;
-	}
-	if (memcmp(fpsimd, &new_fpsimd, sizeof(*fpsimd)) == 0)
-		ksft_test_result_pass("get_fpsimd() gave same state\n");
-	else
-		ksft_test_result_fail("get_fpsimd() gave different state\n");
+	/* FPSIMD via SVE regset */
+	ptrace_sve_fpsimd(child);
 
 	/* Step through every possible VQ */
 	for (vq = SVE_VQ_MIN; vq <= SVE_VQ_MAX; vq++) {