linux-kernel - Re: [PATCH] ACPI: Add GPIO-signaled event emulator.

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:	Thu, 21 Aug 2014 17:54:05 +0300
From:	Mika Westerberg <mika.westerberg@...ux.intel.com>
To:	Tomasz Nowicki <tomasz.nowicki@...aro.org>
Cc:	rjw@...ysocki.net, linus.walleij@...aro.org, gnurou@...il.com,
	linux-acpi@...r.kernel.org, linux-kernel@...r.kernel.org,
	linaro-acpi@...ts.linaro.org
Subject: Re: [PATCH] ACPI: Add GPIO-signaled event emulator.

On Thu, Aug 21, 2014 at 04:39:46PM +0200, Tomasz Nowicki wrote:
> >>+{
> >>+	struct gpio_pin_data *pin_data, *temp;
> >>+
> >>+	list_for_each_entry_safe(pin_data, temp, &pin_data_list, list)
> >>+		kfree(pin_data);
> >
> >I suppose you want to first remove the directory entries and then the
> >pin data. Otherwise if you get pre-empted at this point and someone
> >tries to use your debugfs files, bad things might happen.
> Good catch!
> 
> >
> >>+
> >>+	debugfs_remove_recursive(acpi_evt_debugfs_dir);
> >
> >Since this already removes everything below this dentry, why do you need
> >to store the pointer in gpio_pin_parent_data?
> Not sure I got the question.
> 
> GPIO device instance (debugfs dir) is parent for all its pins (debugfs
> nodes). I am using gpio_pin_parent_data as container to pass info for all
> children so I can create debugfs node inside of parent related debugfs dir.
> 
> pin_data_list, however, is used to keep pointers to allocated memory (one
> for each pins). debugfs_remove_recursive won't free it.

Yes but it removes the debugfs entries below so you don't need to store
the children debugfs dentries.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/