linux-kernel - [153/272] i2c: Unregister dummy devices last on adapter removal

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:	Tue, 15 Feb 2011 16:13:30 -0800
From:	Greg KH <gregkh@...e.de>
To:	linux-kernel@...r.kernel.org, stable@...nel.org
Cc:	stable-review@...nel.org, torvalds@...ux-foundation.org,
	akpm@...ux-foundation.org, alan@...rguk.ukuu.org.uk,
	Jean Delvare <khali@...ux-fr.org>
Subject: [153/272] i2c: Unregister dummy devices last on adapter removal

2.6.37-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Jean Delvare <khali@...ux-fr.org>

commit 5219bf884b6e2b54e734ca1799b6f0014bb2b4b7 upstream.

Remove real devices first and dummy devices last. This gives device
driver which instantiated dummy devices themselves a chance to clean
them up before we do.

Signed-off-by: Jean Delvare <khali@...ux-fr.org>
Tested-by: Hans Verkuil <hverkuil@...all.nl>
Signed-off-by: Greg Kroah-Hartman <gregkh@...e.de>

---
 drivers/i2c/i2c-core.c |   14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -1021,6 +1021,14 @@ static int i2c_do_del_adapter(struct i2c
 static int __unregister_client(struct device *dev, void *dummy)
 {
 	struct i2c_client *client = i2c_verify_client(dev);
+	if (client && strcmp(client->name, "dummy"))
+		i2c_unregister_device(client);
+	return 0;
+}
+
+static int __unregister_dummy(struct device *dev, void *dummy)
+{
+	struct i2c_client *client = i2c_verify_client(dev);
 	if (client)
 		i2c_unregister_device(client);
 	return 0;
@@ -1075,8 +1083,12 @@ int i2c_del_adapter(struct i2c_adapter *
 	mutex_unlock(&adap->userspace_clients_lock);
 
 	/* Detach any active clients. This can't fail, thus we do not
-	   checking the returned value. */
+	 * check the returned value. This is a two-pass process, because
+	 * we can't remove the dummy devices during the first pass: they
+	 * could have been instantiated by real devices wishing to clean
+	 * them up properly, so we give them a chance to do that first. */
 	res = device_for_each_child(&adap->dev, NULL, __unregister_client);
+	res = device_for_each_child(&adap->dev, NULL, __unregister_dummy);
 
 #ifdef CONFIG_I2C_COMPAT
 	class_compat_remove_link(i2c_adapter_compat_class, &adap->dev,


--
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/