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From: Ingo Flaschberger <ingo.flaschberger@gmail.com>
To: linux-kernel@vger.kernel.org
Subject: unbind/bind w1-gpio with device tree produce a crash
Date: Wed, 04 Mar 2015 04:53:06 +0100	[thread overview]
Message-ID: <54F681A2.9020803@gmail.com> (raw)

If w1-gpio is probed via device-tree configuration, pdata is allocated 
via devm_kzalloc.
When the device is unbind (and bind later) the allocated memory of pdate 
is freed - but it will not be allocacted again.

static int w1_gpio_probe(struct platform_device *pdev)
         struct w1_bus_master *master;
         struct w1_gpio_platform_data *pdata = pdev->dev.platform_data;
         int err;

         if(pdata == NULL) {
                 if (of_have_populated_dt()) {
                         err = w1_gpio_probe_dt(pdev);
                         if (err < 0)
                                 return err;
                 }
         }

How to detect if pdata was allocated via device-tree devm_kzalloc and 
not "hardcoded"?
Then I could set pdev->dev.platform_data to NULL in w1_gpio_remove which 
will solve the crash.

Kind regards,
    Ingo Flascherger


             reply	other threads:[~2015-03-04  3:51 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-03-04  3:53 Ingo Flaschberger [this message]
2015-03-04 16:38 ` Ingo Flaschberger
     [not found]   ` <54F7C5D4.3000604@gmail.com>
2015-03-05  7:35     ` Fwd: " Markus Pargmann
2015-03-05 11:56       ` Ingo Flaschberger
2015-03-09 10:18         ` [PATCH] w1: gpio: Fix problematic platform_data usage Markus Pargmann
2015-04-10 10:22           ` Markus Pargmann
2016-03-22 11:59             ` Ingo Flaschberger

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