Commit c5a814cc authored by Michael Ellerman's avatar Michael Ellerman
Browse files

selftests/powerpc/ptrace: Use more interesting values 



The ptrace-gpr test uses fixed values to test that registers can be
read/written via ptrace. In particular it sets all GPRs to 1, which
means the test could miss some types of bugs - eg. if the kernel was
only returning the low word.

So generate some random values at startup and use those instead.

Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220627140239.2464900-12-mpe@ellerman.id.au
parent 7b1513d0

tools/testing/selftests/powerpc/ptrace/ptrace-gpr.c

+57 −14
Original line number Original line Diff line number Diff line
@@ -7,18 +7,18 @@ 
#include "ptrace.h"

#include "ptrace.h"

#include "ptrace-gpr.h"

#include "ptrace-gpr.h"

#include "reg.h"

#include "reg.h"

#include <time.h>





/* Tracer and Tracee Shared Data */

/* Tracer and Tracee Shared Data */

int shm_id;

int shm_id;

int *cptr, *pptr;

int *cptr, *pptr;





double a = FPR_1;

double b = FPR_2;

double c = FPR_3;



extern void gpr_child_loop(int *read_flag, int *write_flag,

extern void gpr_child_loop(int *read_flag, int *write_flag,

			   unsigned long *gpr_buf, double *fpr_buf);

			   unsigned long *gpr_buf, double *fpr_buf);





unsigned long child_gpr_val, parent_gpr_val;

double child_fpr_val, parent_fpr_val;



static int child(void)

static int child(void)

{

{

	unsigned long gpr_buf[32];

	unsigned long gpr_buf[32];
@@ -30,16 +30,16 @@ static int child(void) 
	memset(fpr_buf, 0, sizeof(fpr_buf));

	memset(fpr_buf, 0, sizeof(fpr_buf));





	for (i = 0; i < 32; i++) {

	for (i = 0; i < 32; i++) {

		gpr_buf[i] = GPR_1;

		gpr_buf[i] = child_gpr_val;

		fpr_buf[i] = a;

		fpr_buf[i] = child_fpr_val;

	}

	}





	gpr_child_loop(&cptr[0], &cptr[1], gpr_buf, fpr_buf);

	gpr_child_loop(&cptr[0], &cptr[1], gpr_buf, fpr_buf);





	shmdt((void *)cptr);

	shmdt((void *)cptr);





	FAIL_IF(validate_gpr(gpr_buf, GPR_3));

	FAIL_IF(validate_gpr(gpr_buf, parent_gpr_val));

	FAIL_IF(validate_fpr_double(fpr_buf, c));

	FAIL_IF(validate_fpr_double(fpr_buf, parent_fpr_val));





	return 0;

	return 0;

}

}
@@ -47,24 +47,67 @@ static int child(void) 
int trace_gpr(pid_t child)

int trace_gpr(pid_t child)

{

{

	unsigned long gpr[18];

	unsigned long gpr[18];

	__u64 fpr[32];

	__u64 tmp, fpr[32];





	FAIL_IF(start_trace(child));

	FAIL_IF(start_trace(child));

	FAIL_IF(show_gpr(child, gpr));

	FAIL_IF(show_gpr(child, gpr));

	FAIL_IF(validate_gpr(gpr, GPR_1));

	FAIL_IF(validate_gpr(gpr, child_gpr_val));

	FAIL_IF(show_fpr(child, fpr));

	FAIL_IF(show_fpr(child, fpr));

	FAIL_IF(validate_fpr(fpr, FPR_1_REP));



	FAIL_IF(write_gpr(child, GPR_3));

	memcpy(&tmp, &child_fpr_val, sizeof(tmp));

	FAIL_IF(write_fpr(child, FPR_3_REP));

	FAIL_IF(validate_fpr(fpr, tmp));



	FAIL_IF(write_gpr(child, parent_gpr_val));



	memcpy(&tmp, &parent_fpr_val, sizeof(tmp));

	FAIL_IF(write_fpr(child, tmp));



	FAIL_IF(stop_trace(child));

	FAIL_IF(stop_trace(child));





	return TEST_PASS;

	return TEST_PASS;

}

}





#ifndef __LONG_WIDTH__

#define __LONG_WIDTH__ (sizeof(long) * 8)

#endif



static uint64_t rand_reg(void)

{

	uint64_t result;

	long r;



	r = random();



	// Small values are typical

	result = r & 0xffff;

	if (r & 0x10000)

		return result;



	// Pointers tend to have high bits set

	result |= random() << (__LONG_WIDTH__ - 31);

	if (r & 0x100000)

		return result;



	// And sometimes we want a full 64-bit value

	result ^= random() << 16;



	return result;

}



int ptrace_gpr(void)

int ptrace_gpr(void)

{

{

	pid_t pid;

	unsigned long seed;

	int ret, status;

	int ret, status;

	pid_t pid;



	seed = getpid() ^ time(NULL);

	printf("srand(%lu)\n", seed);

	srand(seed);



	child_gpr_val = rand_reg();

	child_fpr_val = rand_reg();

	parent_gpr_val = rand_reg();

	parent_fpr_val = rand_reg();





	shm_id = shmget(IPC_PRIVATE, sizeof(int) * 2, 0777|IPC_CREAT);

	shm_id = shmget(IPC_PRIVATE, sizeof(int) * 2, 0777|IPC_CREAT);

	pid = fork();

	pid = fork();