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Revision dc280d93623927570da279e99393879dbbab39e7 authored by Thomas Gleixner on 21 December 2016, 19:19:49 UTC, committed by Thomas Gleixner on 25 December 2016, 09:47:42 UTC 
cpu/hotplug: Prevent overwriting of callbacks
 
Developers manage to overwrite states blindly without thought. That's fatal
and hard to debug. Add sanity checks to make it fail.

This requries to restructure the code so that the dynamic state allocation
happens in the same lock protected section as the actual store. Otherwise
the previous assignment of 'Reserved' to the name field would trigger the
overwrite check.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Link: http://lkml.kernel.org/r/20161221192111.675234535@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
1 parent 59fefd0
Raw File
sa1100_assabet.c 
/*
 * drivers/pcmcia/sa1100_assabet.c
 *
 * PCMCIA implementation routines for Assabet
 *
 */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/device.h>
#include <linux/init.h>
#include <linux/gpio.h>

#include <asm/mach-types.h>
#include <mach/assabet.h>

#include "sa1100_generic.h"

static int assabet_pcmcia_hw_init(struct soc_pcmcia_socket *skt)
{
	skt->stat[SOC_STAT_CD].gpio = ASSABET_GPIO_CF_CD;
	skt->stat[SOC_STAT_CD].name = "CF CD";
	skt->stat[SOC_STAT_BVD1].gpio = ASSABET_GPIO_CF_BVD1;
	skt->stat[SOC_STAT_BVD1].name = "CF BVD1";
	skt->stat[SOC_STAT_BVD2].gpio = ASSABET_GPIO_CF_BVD2;
	skt->stat[SOC_STAT_BVD2].name = "CF BVD2";
	skt->stat[SOC_STAT_RDY].gpio = ASSABET_GPIO_CF_IRQ;
	skt->stat[SOC_STAT_RDY].name = "CF RDY";

	return 0;
}

static int
assabet_pcmcia_configure_socket(struct soc_pcmcia_socket *skt, const socket_state_t *state)
{
	unsigned int mask;

	switch (state->Vcc) {
	case 0:
		mask = 0;
		break;

	case 50:
		printk(KERN_WARNING "%s(): CS asked for 5V, applying 3.3V...\n",
			__func__);

	case 33:  /* Can only apply 3.3V to the CF slot. */
		mask = ASSABET_BCR_CF_PWR;
		break;

	default:
		printk(KERN_ERR "%s(): unrecognized Vcc %u\n", __func__,
			state->Vcc);
		return -1;
	}

	/* Silently ignore Vpp, speaker enable. */

	if (state->flags & SS_RESET)
		mask |= ASSABET_BCR_CF_RST;
	if (!(state->flags & SS_OUTPUT_ENA))
		mask |= ASSABET_BCR_CF_BUS_OFF;

	ASSABET_BCR_frob(ASSABET_BCR_CF_RST | ASSABET_BCR_CF_PWR |
			ASSABET_BCR_CF_BUS_OFF, mask);

	return 0;
}

/*
 * Disable card status IRQs on suspend.
 */
static void assabet_pcmcia_socket_suspend(struct soc_pcmcia_socket *skt)
{
	/*
	 * Tristate the CF bus signals.  Also assert CF
	 * reset as per user guide page 4-11.
	 */
	ASSABET_BCR_set(ASSABET_BCR_CF_BUS_OFF | ASSABET_BCR_CF_RST);
}

static struct pcmcia_low_level assabet_pcmcia_ops = { 
	.owner			= THIS_MODULE,
	.hw_init		= assabet_pcmcia_hw_init,
	.socket_state		= soc_common_cf_socket_state,
	.configure_socket	= assabet_pcmcia_configure_socket,
	.socket_suspend		= assabet_pcmcia_socket_suspend,
};

int pcmcia_assabet_init(struct device *dev)
{
	int ret = -ENODEV;

	if (machine_is_assabet() && !machine_has_neponset())
		ret = sa11xx_drv_pcmcia_probe(dev, &assabet_pcmcia_ops, 1, 1);

	return ret;
}
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