// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright 2016, Cyril Bur, IBM Corp.
*
* Test the kernel's signal frame code.
*
* The kernel sets up two sets of ucontexts if the signal was to be
* delivered while the thread was in a transaction (referred too as
* first and second contexts).
* Expected behaviour is that the checkpointed state is in the user
* context passed to the signal handler (first context). The speculated
* state can be accessed with the uc_link pointer (second context).
*
* The rationale for this is that if TM unaware code (which linked
* against TM libs) installs a signal handler it will not know of the
* speculative nature of the 'live' registers and may infer the wrong
* thing.
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <signal.h>
#include <unistd.h>
#include <altivec.h>
#include "utils.h"
#include "tm.h"
#define MAX_ATTEMPT 500000
#define NV_VMX_REGS 12 /* Number of non-volatile VMX registers */
#define VMX20 20 /* First non-volatile register to check in vr20-31 subset */
long tm_signal_self_context_load(pid_t pid, long *gprs, double *fps, vector int *vms, vector int *vss);
static sig_atomic_t fail, broken;
/* Test only non-volatile registers, i.e. 12 vmx registers from vr20 to vr31 */
vector int vms[] = {
/* First context will be set with these values, i.e. non-speculative */
/* VMX20 , VMX21 , ... */
{ 1, 2, 3, 4},{ 5, 6, 7, 8},{ 9,10,11,12},
{13,14,15,16},{17,18,19,20},{21,22,23,24},
{25,26,27,28},{29,30,31,32},{33,34,35,36},
{37,38,39,40},{41,42,43,44},{45,46,47,48},
/* Second context will be set with these values, i.e. speculative */
/* VMX20 , VMX21 , ... */
{ -1, -2, -3, -4},{ -5, -6, -7, -8},{ -9,-10,-11,-12},
{-13,-14,-15,-16},{-17,-18,-19,-20},{-21,-22,-23,-24},
{-25,-26,-27,-28},{-29,-30,-31,-32},{-33,-34,-35,-36},
{-37,-38,-39,-40},{-41,-42,-43,-44},{-45,-46,-47,-48}
};
static void signal_usr1(int signum, siginfo_t *info, void *uc)
{
int i, j;
ucontext_t *ucp = uc;
ucontext_t *tm_ucp = ucp->uc_link;
for (i = 0; i < NV_VMX_REGS; i++) {
/* Check first context. Print all mismatches. */
fail = memcmp(ucp->uc_mcontext.v_regs->vrregs[VMX20 + i],
&vms[i], sizeof(vector int));
if (fail) {
broken = 1;
printf("VMX%d (1st context) == 0x", VMX20 + i);
/* Print actual value in first context. */
for (j = 0; j < 4; j++)
printf("%08x", ucp->uc_mcontext.v_regs->vrregs[VMX20 + i][j]);
printf(" instead of 0x");
/* Print expected value. */
for (j = 0; j < 4; j++)
printf("%08x", vms[i][j]);
printf(" (expected)\n");
}
}
for (i = 0; i < NV_VMX_REGS; i++) {
/* Check second context. Print all mismatches. */
fail = memcmp(tm_ucp->uc_mcontext.v_regs->vrregs[VMX20 + i],
&vms[NV_VMX_REGS + i], sizeof (vector int));
if (fail) {
broken = 1;
printf("VMX%d (2nd context) == 0x", NV_VMX_REGS + i);
/* Print actual value in second context. */
for (j = 0; j < 4; j++)
printf("%08x", tm_ucp->uc_mcontext.v_regs->vrregs[VMX20 + i][j]);
printf(" instead of 0x");
/* Print expected value. */
for (j = 0; j < 4; j++)
printf("%08x", vms[NV_VMX_REGS + i][j]);
printf(" (expected)\n");
}
}
}
static int tm_signal_context_chk()
{
struct sigaction act;
int i;
long rc;
pid_t pid = getpid();
SKIP_IF(!have_htm());
SKIP_IF(htm_is_synthetic());
act.sa_sigaction = signal_usr1;
sigemptyset(&act.sa_mask);
act.sa_flags = SA_SIGINFO;
if (sigaction(SIGUSR1, &act, NULL) < 0) {
perror("sigaction sigusr1");
exit(1);
}
i = 0;
while (i < MAX_ATTEMPT && !broken) {
/*
* tm_signal_self_context_load will set both first and second
* contexts accordingly to the values passed through non-NULL
* array pointers to it, in that case 'vms', and invoke the
* signal handler installed for SIGUSR1.
*/
rc = tm_signal_self_context_load(pid, NULL, NULL, vms, NULL);
FAIL_IF(rc != pid);
i++;
}
return (broken);
}
int main(void)
{
return test_harness(tm_signal_context_chk, "tm_signal_context_chk_vmx");
}
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