From: Greg KH <greg@kroah•com>
To: "Eric W. Biederman" <ebiederm@xmission•com>
Cc: Johannes Berg <johannes@sipsolutions•net>,
netdev <netdev@vger•kernel.org>,
Kay Sievers <kay.sievers@vrfy•org>
Subject: Re: [PATCH] Driver-core: Always create network class directories in get_device_parent.
Date: Mon, 21 Jun 2010 15:20:47 -0700 [thread overview]
Message-ID: <20100621222047.GA27848@kroah.com> (raw)
In-Reply-To: <m1ocf5hnwh.fsf_-_@fess.ebiederm.org>
On Sun, Jun 20, 2010 at 05:46:54AM -0700, Eric W. Biederman wrote:
>
> In get_device_parent there was added check to not add a class
> directory when a class device was put under another class device. The
> check was put in place as a just in case measure to not break old
> userspace if any existing code happened to depend on it. Devices in
> the input subsystem are affected by this code path so there is a
> reasonable chance that some piece of user space will break if we just
> remove this kludge.
>
> At the same time there are at least two network drivers that have
> potential unnecessary namespace conflicts because class directories
> have not been created for their network devices.
>
> With the introduction of tagged sysfs directories for properly
> handling network namespace support this omission in creating the class
> directories went from a bad thing in terms of namespace pollution, to
> actually breaking device_remove.
>
> Currently there are two reported network device drivers that break
> because the class directory was not created by the device layer. The
> usb bnep driver and the mac80211_hwsim driver.
>
> Every solution proposed changes the sysfs layout for the affected
> devices, and thus has the potential to break userspace.
>
> Since we are changing the sysfs layout anyway, and since we are now
> talking about several devices all with the same problem, all caused by
> the same over convservative bit of code. Let's fix the device layer
> for network devices.
>
> Signed-off-by: Eric W. Biederman <ebiederm@xmission•com>
> ---
> drivers/base/core.c | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/base/core.c b/drivers/base/core.c
> index 9630fbd..ffb8443 100644
> --- a/drivers/base/core.c
> +++ b/drivers/base/core.c
> @@ -673,7 +673,7 @@ static struct kobject *get_device_parent(struct device *dev,
> */
> if (parent == NULL)
> parent_kobj = virtual_device_parent(dev);
> - else if (parent->class)
> + else if (parent->class && (strcmp(dev->class->name, "net") != 0))
No, we will not have subsystem specific hacks in the driver core like
this. What would cause us to ever be able to delete this line?
thanks,
greg k-h
next prev parent reply other threads:[~2010-06-21 22:20 UTC|newest]
Thread overview: 58+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-06-02 13:16 sysfs class/net/ problem Johannes Berg
2010-06-02 15:46 ` Greg KH
2010-06-02 15:48 ` Johannes Berg
2010-06-02 16:17 ` Eric W. Biederman
2010-06-02 16:21 ` Johannes Berg
2010-06-02 16:43 ` Eric W. Biederman
2010-06-02 17:00 ` Johannes Berg
2010-06-02 17:23 ` Eric W. Biederman
2010-06-02 17:52 ` Johannes Berg
2010-06-02 18:05 ` Eric W. Biederman
2010-06-02 18:55 ` Johannes Berg
2010-06-02 19:12 ` Johannes Berg
2010-06-02 19:25 ` Johannes Berg
2010-06-02 23:09 ` Eric W. Biederman
2010-06-03 0:53 ` [RFC][PATCH] Fix another namespace issue with devices assigned to classes Eric W. Biederman
2010-06-03 9:30 ` Kay Sievers
2010-06-03 10:00 ` Eric W. Biederman
2010-06-04 6:54 ` Johannes Berg
2010-06-04 8:15 ` Kay Sievers
2010-06-04 8:28 ` Johannes Berg
2010-06-04 8:34 ` Kay Sievers
2010-06-06 13:08 ` Johannes Berg
2010-06-06 17:17 ` Kay Sievers
2010-06-07 9:42 ` Johannes Berg
2010-06-07 9:53 ` Kay Sievers
2010-06-07 10:14 ` Johannes Berg
2010-06-07 11:05 ` Kay Sievers
2010-06-07 11:41 ` Johannes Berg
2010-06-07 12:26 ` Kay Sievers
2010-06-07 12:36 ` Johannes Berg
2010-06-07 12:54 ` Kay Sievers
2010-06-08 9:27 ` Johannes Berg
2010-06-08 9:30 ` Kay Sievers
2010-06-08 9:45 ` Johannes Berg
2010-06-08 11:55 ` Kay Sievers
2010-06-08 12:03 ` Johannes Berg
2010-06-08 13:54 ` Kay Sievers
2010-06-08 14:06 ` Johannes Berg
2010-06-08 14:21 ` Kay Sievers
2010-06-08 14:26 ` Johannes Berg
2010-06-08 14:47 ` Kay Sievers
2010-06-08 15:06 ` Johannes Berg
2010-06-08 16:26 ` Kay Sievers
2010-06-08 16:33 ` Johannes Berg
2010-06-08 16:39 ` Kay Sievers
2010-06-11 9:55 ` Johannes Berg
2010-06-14 9:13 ` Kay Sievers
2010-06-14 9:20 ` Johannes Berg
2010-06-14 9:39 ` Kay Sievers
2010-06-20 6:20 ` [PATCH] Driver-core: Always create class directories fixing the broken network drivers Eric W. Biederman
2010-06-20 10:52 ` Kay Sievers
2010-06-20 11:33 ` Johannes Berg
2010-06-20 11:46 ` Kay Sievers
2010-06-20 12:29 ` Eric W. Biederman
2010-06-20 13:37 ` Kay Sievers
2010-06-20 12:46 ` [PATCH] Driver-core: Always create network class directories in get_device_parent Eric W. Biederman
2010-06-21 22:20 ` Greg KH [this message]
2010-06-21 23:00 ` Eric W. Biederman
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