śr., 10 lip 2019 o 11:37 Phil Reid preid@electromag.com.au napisał(a):

G'day Bartosz,

One comment below

On 10/07/2019 17:08, Bartosz Golaszewski wrote:

...

From: Bartosz Golaszewski bgolaszewski@baylibre.com

In commit 8764c4ca5049 ("gpio: em: use the managed version of gpiochip_add_data()") we implicitly altered the ordering of resource freeing: since gpiochip_remove() calls gpiochip_irqchip_remove() internally, we now can potentially use the irq_domain after it was destroyed in the remove() callback (as devm resources are freed after remove() has returned).

Use devm_add_action() to keep the ordering right and entirely kill the remove() callback in the driver.

Reported-by: Geert Uytterhoeven geert@linux-m68k.org Fixes: 8764c4ca5049 ("gpio: em: use the managed version of gpiochip_add_data()") Cc: stable@vger.kernel.org Signed-off-by: Bartosz Golaszewski bgolaszewski@baylibre.com

---

drivers/gpio/gpio-em.c | 35 +++++++++++++++++------------------ 1 file changed, 17 insertions(+), 18 deletions(-)

diff --git a/drivers/gpio/gpio-em.c b/drivers/gpio/gpio-em.c index b6af705a4e5f..c88028ac66f2 100644 --- a/drivers/gpio/gpio-em.c +++ b/drivers/gpio/gpio-em.c @@ -259,6 +259,13 @@ static const struct irq_domain_ops em_gio_irq_domain_ops = { .xlate = irq_domain_xlate_twocell, };

+static void em_gio_irq_domain_remove(void *data) +{

• struct irq_domain *domain = data;
  

• irq_domain_remove(domain);
  

+}

• static int em_gio_probe(struct platform_device *pdev) { struct em_gio_priv *p;

@@ -333,39 +340,32 @@ static int em_gio_probe(struct platform_device *pdev) return -ENXIO; }

• ret = devm_add_action(&pdev->dev,
  

•                       em_gio_irq_domain_remove, p->irq_domain);
  

Could devm_add_action_or_reset be used?

Of course it could and it should. :)

I'll resend tomorrow to not spam the mailing list.

Thanks, Bart

...

• if (ret) {
  

•         irq_domain_remove(p->irq_domain);
  

•         return ret;
  

• }
  

• if (devm_request_irq(&pdev->dev, irq[0]->start,
                       em_gio_irq_handler, 0, name, p)) {
          dev_err(&pdev->dev, "failed to request low IRQ\n");
  

•         ret = -ENOENT;
  

•         goto err1;
  

•         return -ENOENT;
  }
  
  if (devm_request_irq(&pdev->dev, irq[1]->start,
                       em_gio_irq_handler, 0, name, p)) {
          dev_err(&pdev->dev, "failed to request high IRQ\n");
  

•         ret = -ENOENT;
  

•         goto err1;
  

•         return -ENOENT;
  }
  
  ret = devm_gpiochip_add_data(&pdev->dev, gpio_chip, p);
  if (ret) {
          dev_err(&pdev->dev, "failed to add GPIO controller\n");
  

•         goto err1;
  

•         return ret;
  }
  
  return 0;
  

-err1:

• irq_domain_remove(p->irq_domain);
  

• return ret;
  

-}

-static int em_gio_remove(struct platform_device *pdev) -{

• struct em_gio_priv *p = platform_get_drvdata(pdev);
  

• irq_domain_remove(p->irq_domain);
  

• return 0;
  

  }

  static const struct of_device_id em_gio_dt_ids[] = {

@@ -376,7 +376,6 @@ MODULE_DEVICE_TABLE(of, em_gio_dt_ids);

static struct platform_driver em_gio_device_driver = { .probe = em_gio_probe,

• .remove         = em_gio_remove,
  .driver         = {
          .name   = "em_gio",
          .of_match_table = em_gio_dt_ids,
  
  

-- Regards Phil Reid