/*
 * Copyright 2015, Cyril Bur, IBM Corp.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 *
 * This test attempts to see if the FPU registers are correctly reported in a
 * signal context. Each worker just spins checking its FPU registers, at some
 * point a signal will interrupt it and C code will check the signal context
 * ensuring it is also the same.
 */

#include <stdio.h>
#include <unistd.h>
#include <sys/syscall.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <stdlib.h>
#include <pthread.h>

#include "utils.h"

/* Number of times each thread should receive the signal */
#define ITERATIONS 10
/*
 * Factor by which to multiply number of online CPUs for total number of
 * worker threads
 */
#define THREAD_FACTOR 8

__thread double darray[] = {0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0,
		     1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0,
		     2.1};

bool bad_context;
int threads_starting;
int running;

extern long preempt_fpu(double *darray, int *threads_starting, int *running);

void signal_fpu_sig(int sig, siginfo_t *info, void *context)
{
	int i;
	ucontext_t *uc = context;
	mcontext_t *mc = &uc->uc_mcontext;

	/* Only the non volatiles were loaded up */
	for (i = 14; i < 32; i++) {
		if (mc->fp_regs[i] != darray[i - 14]) {
			bad_context = true;
			break;
		}
	}
}

void *signal_fpu_c(void *p)
{
	int i;
	long rc;
	struct sigaction act;
	act.sa_sigaction = signal_fpu_sig;
	act.sa_flags = SA_SIGINFO;
	rc = sigaction(SIGUSR1, &act, NULL);
	if (rc)
		return p;

	srand(pthread_self());
	for (i = 0; i < 21; i++)
		darray[i] = rand();

	rc = preempt_fpu(darray, &threads_starting, &running);

	return (void *) rc;
}

int test_signal_fpu(void)
{
	int i, j, rc, threads;
	void *rc_p;
	pthread_t *tids;

	threads = sysconf(_SC_NPROCESSORS_ONLN) * THREAD_FACTOR;
	tids = malloc(threads * sizeof(pthread_t));
	FAIL_IF(!tids);

	running = true;
	threads_starting = threads;
	for (i = 0; i < threads; i++) {
		rc = pthread_create(&tids[i], NULL, signal_fpu_c, NULL);
		FAIL_IF(rc);
	}

	setbuf(stdout, NULL);
	printf("\tWaiting for all workers to start...");
	while (threads_starting)
		asm volatile("": : :"memory");
	printf("done\n");

	printf("\tSending signals to all threads %d times...", ITERATIONS);
	for (i = 0; i < ITERATIONS; i++) {
		for (j = 0; j < threads; j++) {
			pthread_kill(tids[j], SIGUSR1);
		}
		sleep(1);
	}
	printf("done\n");

	printf("\tStopping workers...");
	running = 0;
	for (i = 0; i < threads; i++) {
		pthread_join(tids[i], &rc_p);

		/*
		 * Harness will say the fail was here, look at why signal_fpu
		 * returned
		 */
		if ((long) rc_p || bad_context)
			printf("oops\n");
		if (bad_context)
			fprintf(stderr, "\t!! bad_context is true\n");
		FAIL_IF((long) rc_p || bad_context);
	}
	printf("done\n");

	free(tids);
	return 0;
}

int main(int argc, char *argv[])
{
	return test_harness(test_signal_fpu, "fpu_signal");
}
type='hidden' name='id' value='030305d69fc6963c16003f50d7e8d74b02d0a143'/><table><tr><td colspan='2'/></tr><tr><td class='label'>context:</td><td class='ctrl'><select name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Bjorn Helgaas &lt;bhelgaas@google.com&gt;</td><td class='right'>2017-01-27 15:00:45 -0600</td></tr>
<tr><th>committer</th><td>Bjorn Helgaas &lt;bhelgaas@google.com&gt;</td><td class='right'>2017-01-27 15:00:45 -0600</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/sound/soc/img?id=030305d69fc6963c16003f50d7e8d74b02d0a143'>030305d69fc6963c16003f50d7e8d74b02d0a143</a> (<a href='/cgit.cgi/linux/net-next.git/patch/sound/soc/img?id=030305d69fc6963c16003f50d7e8d74b02d0a143'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=030305d69fc6963c16003f50d7e8d74b02d0a143'>363a4e34d199178769b7e7eeb26ea2620a55847b</a> /<a href='/cgit.cgi/linux/net-next.git/tree/sound/soc/img?id=030305d69fc6963c16003f50d7e8d74b02d0a143'>sound/soc/img</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/sound/soc/img?id=4d191b1b63c209e37bf27938ef365244d3c41084'>4d191b1b63c209e37bf27938ef365244d3c41084</a> (<a href='/cgit.cgi/linux/net-next.git/diff/sound/soc/img?id=030305d69fc6963c16003f50d7e8d74b02d0a143&amp;id2=4d191b1b63c209e37bf27938ef365244d3c41084'>diff</a>)</td></tr></table>
<div class='commit-subject'>PCI/ASPM: Handle PCI-to-PCIe bridges as roots of PCIe hierarchies</div><div class='commit-msg'>In a struct pcie_link_state, link-&gt;root points to the pcie_link_state of
the root of the PCIe hierarchy.  For the topmost link, this points to
itself (link-&gt;root = link).  For others, we copy the pointer from the
parent (link-&gt;root = link-&gt;parent-&gt;root).

Previously we recognized that Root Ports originated PCIe hierarchies, but
we treated PCI/PCI-X to PCIe Bridges as being in the middle of the
hierarchy, and when we tried to copy the pointer from link-&gt;parent-&gt;root,
there was no parent, and we dereferenced a NULL pointer:

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000090
  IP: [&lt;ffffffff9e424350&gt;] pcie_aspm_init_link_state+0x170/0x820

Recognize that PCI/PCI-X to PCIe Bridges originate PCIe hierarchies just
like Root Ports do, so link-&gt;root for these devices should also point to
itself.

Fixes: 51ebfc92b72b ("PCI: Enumerate switches below PCI-to-PCIe bridges")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=193411
Link: https://bugzilla.opensuse.org/show_bug.cgi?id=1022181
Tested-by: lists@ssl-mail.com
Tested-by: Jayachandran C. &lt;jnair@caviumnetworks.com&gt;
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
CC: stable@vger.kernel.org	# v4.2+</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=030305d69fc6963c16003f50d7e8d74b02d0a143'>Diffstat</a> (limited to 'sound/soc/img')</div><table summary='diffstat' class='diffstat'>