lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Wed, 07 Jan 2015 17:30:11 +0100
From:	Marc Kleine-Budde <mkl@...gutronix.de>
To:	Sören Brinkmann <soren.brinkmann@...inx.com>
CC:	Kedareswara rao Appana <appana.durga.rao@...inx.com>,
	wg@...ndegger.com, michal.simek@...inx.com,
	grant.likely@...aro.org, linux-can@...r.kernel.org,
	netdev@...r.kernel.org, linux-kernel@...r.kernel.org,
	Kedareswara rao Appana <appanad@...inx.com>
Subject: Re: [PATCH v4] can: Convert to runtime_pm

On 01/07/2015 04:58 PM, Sören Brinkmann wrote:
>> I think you have to convert the _remove() function, too. Have a look at
>> the gpio-zynq.c driver:
>>
>>> static int zynq_gpio_remove(struct platform_device *pdev)
>>> {
>>> 	struct zynq_gpio *gpio = platform_get_drvdata(pdev);
>>>
>>> 	pm_runtime_get_sync(&pdev->dev);
>>
>> However I don't understand why the get_sync() is here. Maybe Sören can help?
> 
> IIRC, the concern was that the remove function may be called while the device is
> runtime suspended. Hence the remove function needs to resume the device since the
> remove function may access the HW.

What about the corresponding runtime_put()? Would some counter be
unbalanced upon device removal?

Without having tested it, unloading and loading, i.e. reloading a CAN
driver is easier than reloading the gpio driver on an average embedded
system. Kedareswara please test your driver with something like:
modprobe; ifconfig up; cansend; ifconfig down; rmmod in a loop.

Marc

-- 
Pengutronix e.K.                  | Marc Kleine-Budde           |
Industrial Linux Solutions        | Phone: +49-231-2826-924     |
Vertretung West/Dortmund          | Fax:   +49-5121-206917-5555 |
Amtsgericht Hildesheim, HRA 2686  | http://www.pengutronix.de   |


Download attachment "signature.asc" of type "application/pgp-signature" (820 bytes)

Powered by blists - more mailing lists