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spi/pxa2xx pci: fix the release - remove race 

Right now the platform device and its platform data is included in one big
struct which requires its custom ->release function. The problem with the
release function within the driver is that it might be called after the
driver was removed because someone was holding a reference to it and it
was not called right after platform_device_unregister(). So we also free
the platform device memory to which one might hold a reference.

This patch uses the normal pdev functions so this kind of race does not
occur.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This commit is contained in:
Sebastian Andrzej Siewior 2011-02-03 00:31:21 +05:30 committed by Grant Likely
parent c170093d31
commit 0f3e1d27a7
1 changed files with 21 additions and 40 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

61
drivers/spi/pxa2xx_spi_pci.c
View File

@ -7,10 +7,9 @@
#include <linux/of_device.h>
#include <linux/spi/pxa2xx_spi.h>
struct awesome_struct {
struct ce4100_info {
struct ssp_device ssp;
struct platform_device spi_pdev;
struct pxa2xx_spi_master spi_pdata;
struct platform_device *spi_pdev;
};
static DEFINE_MUTEX(ssp_lock);
@ -51,23 +50,15 @@ void pxa_ssp_free(struct ssp_device *ssp)
}
EXPORT_SYMBOL_GPL(pxa_ssp_free);
static void plat_dev_release(struct device *dev)
{
struct awesome_struct *as = container_of(dev,
struct awesome_struct, spi_pdev.dev);
of_device_node_put(&as->spi_pdev.dev);
}
static int __devinit ce4100_spi_probe(struct pci_dev *dev,
const struct pci_device_id *ent)
{
int ret;
resource_size_t phys_beg;
resource_size_t phys_len;
struct awesome_struct *spi_info;
struct ce4100_info *spi_info;
struct platform_device *pdev;
struct pxa2xx_spi_master *spi_pdata;
struct pxa2xx_spi_master spi_pdata;
struct ssp_device *ssp;
ret = pci_enable_device(dev);
@ -84,33 +75,30 @@ static int __devinit ce4100_spi_probe(struct pci_dev *dev,
return ret;
}
pdev = platform_device_alloc("pxa2xx-spi", dev->devfn);
spi_info = kzalloc(sizeof(*spi_info), GFP_KERNEL);
if (!spi_info) {
if (!pdev || !spi_info ) {
ret = -ENOMEM;
goto err_kz;
goto err_nomem;
}
ssp = &spi_info->ssp;
pdev = &spi_info->spi_pdev;
spi_pdata = &spi_info->spi_pdata;
memset(&spi_pdata, 0, sizeof(spi_pdata));
spi_pdata.num_chipselect = dev->devfn;
ret = platform_device_add_data(pdev, &spi_pdata, sizeof(spi_pdata));
if (ret)
goto err_nomem;
pdev->name = "pxa2xx-spi";
pdev->id = dev->devfn;
pdev->dev.parent = &dev->dev;
pdev->dev.platform_data = &spi_info->spi_pdata;
#ifdef CONFIG_OF
pdev->dev.of_node = dev->dev.of_node;
#endif
pdev->dev.release = plat_dev_release;
spi_pdata->num_chipselect = dev->devfn;
ssp = &spi_info->ssp;
ssp->phys_base = pci_resource_start(dev, 0);
ssp->mmio_base = ioremap(phys_beg, phys_len);
if (!ssp->mmio_base) {
dev_err(&pdev->dev, "failed to ioremap() registers\n");
ret = -EIO;
goto err_remap;
goto err_nomem;
}
ssp->irq = dev->irq;
ssp->port_id = pdev->id;
@ -122,7 +110,7 @@ static int __devinit ce4100_spi_probe(struct pci_dev *dev,
pci_set_drvdata(dev, spi_info);
ret = platform_device_register(pdev);
ret = platform_device_add(pdev);
if (ret)
goto err_dev_add;
@ -135,27 +123,21 @@ static int __devinit ce4100_spi_probe(struct pci_dev *dev,
mutex_unlock(&ssp_lock);
iounmap(ssp->mmio_base);
err_remap:
kfree(spi_info);
err_kz:
err_nomem:
release_mem_region(phys_beg, phys_len);
platform_device_put(pdev);
kfree(spi_info);
return ret;
}
static void __devexit ce4100_spi_remove(struct pci_dev *dev)
{
struct awesome_struct *spi_info;
struct platform_device *pdev;
struct ce4100_info *spi_info;
struct ssp_device *ssp;
spi_info = pci_get_drvdata(dev);
ssp = &spi_info->ssp;
pdev = &spi_info->spi_pdev;
platform_device_unregister(pdev);
platform_device_unregister(spi_info->spi_pdev);
iounmap(ssp->mmio_base);
release_mem_region(pci_resource_start(dev, 0),
@ -171,7 +153,6 @@ static void __devexit ce4100_spi_remove(struct pci_dev *dev)
}
static struct pci_device_id ce4100_spi_devices[] __devinitdata = {
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2e6a) },
{ },
};