selftests/powerpc: Add test to check if VSRs are corrupted

tm-syscall

tm-signal-msr-resv

tm-signal-stack

tm-vmxcopy

TEST_PROGS := tm-resched-dscr tm-syscall tm-signal-msr-resv tm-signal-stack

TEST_PROGS := tm-resched-dscr tm-syscall tm-signal-msr-resv tm-signal-stack tm-vmxcopy

all: $(TEST_PROGS)

/*

 * Copyright 2015, Michael Neuling, IBM Corp.

 * Licensed under GPLv2.

 *

 * Original: Michael Neuling 4/12/2013

 * Edited: Rashmica Gupta 4/12/2015

 *

 * See if the altivec state is leaked out of an aborted transaction due to

 * kernel vmx copy loops.

 *

 * When the transaction aborts, VSR values should rollback to the values

 * they held before the transaction commenced. Using VSRs while transaction

 * is suspended should not affect the checkpointed values.

 *

 * (1) write A to a VSR

 * (2) start transaction

 * (3) suspend transaction

 * (4) change the VSR to B

 * (5) trigger kernel vmx copy loop

 * (6) abort transaction

 * (7) check that the VSR value is A

 */

#include <inttypes.h>

#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

#include <sys/mman.h>

#include <string.h>

#include <assert.h>

#include "tm.h"

#include "utils.h"

int test_vmxcopy()

{

	long double vecin = 1.3;

	long double vecout;

	unsigned long pgsize = getpagesize();

	int i;

	int fd;

	int size = pgsize*16;

	char tmpfile[] = "/tmp/page_faultXXXXXX";

	char buf[pgsize];

	char *a;

	uint64_t aborted = 0;

	SKIP_IF(!have_htm());

	fd = mkstemp(tmpfile);

	assert(fd >= 0);

	memset(buf, 0, pgsize);

	for (i = 0; i < size; i += pgsize)

		assert(write(fd, buf, pgsize) == pgsize);

	unlink(tmpfile);

	a = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);

	assert(a != MAP_FAILED);

	asm __volatile__(

		"lxvd2x 40,0,%[vecinptr];"	/* set 40 to initial value*/

		"tbegin.;"

		"beq	3f;"

		"tsuspend.;"

		"xxlxor 40,40,40;"		/* set 40 to 0 */

		"std	5, 0(%[map]);"		/* cause kernel vmx copy page */

		"tabort. 0;"

		"tresume.;"

		"tend.;"

		"li	%[res], 0;"

		"b	5f;"

		/* Abort handler */

		"3:;"

		"li	%[res], 1;"

		"5:;"

		"stxvd2x 40,0,%[vecoutptr];"

		: [res]"=r"(aborted)

		: [vecinptr]"r"(&vecin),

		  [vecoutptr]"r"(&vecout),

		  [map]"r"(a)

		: "memory", "r0", "r3", "r4", "r5", "r6", "r7");

	if (aborted && (vecin != vecout)){

		printf("FAILED: vector state leaked on abort %f != %f\n",

		       (double)vecin, (double)vecout);

		return 1;

	}

	munmap(a, size);

	close(fd);

	return 0;

}

int main(void)

{

	return test_harness(test_vmxcopy, "tm_vmxcopy");

}