diff mbox

[3.16.y-ckt,stable] Patch "drivercore: Fix unregistration path of platform devices" has been added to staging queue

Message ID 1443460878-3800-1-git-send-email-luis.henriques@canonical.com
State New
Headers show

Commit Message

Luis Henriques Sept. 28, 2015, 5:21 p.m. UTC
This is a note to let you know that I have just added a patch titled

    drivercore: Fix unregistration path of platform devices

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt18.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

From 9965eafeba2c79a5b05e4d456fe9a8d7411ed544 Mon Sep 17 00:00:00 2001
From: Grant Likely <grant.likely@linaro.org>
Date: Sun, 7 Jun 2015 15:20:11 +0100
Subject: drivercore: Fix unregistration path of platform devices

commit 7f5dcaf1fdf289767a126a0a5cc3ef39b5254b06 upstream.

The unregister path of platform_device is broken. On registration, it
will register all resources with either a parent already set, or
type==IORESOURCE_{IO,MEM}. However, on unregister it will release
everything with type==IORESOURCE_{IO,MEM}, but ignore the others. There
are also cases where resources don't get registered in the first place,
like with devices created by of_platform_populate()*.

Fix the unregister path to be symmetrical with the register path by
checking the parent pointer instead of the type field to decide which
resources to unregister. This is safe because the upshot of the
registration path algorithm is that registered resources have a parent
pointer, and non-registered resources do not.

* It can be argued that of_platform_populate() should be registering
  it's resources, and they argument has some merit. However, there are
  quite a few platforms that end up broken if we try to do that due to
  overlapping resources in the device tree. Until that is fixed, we need
  to solve the immediate problem.

Cc: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Cc: Wolfram Sang <wsa@the-dreams.de>
Cc: Rob Herring <robh@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Tested-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
---
 drivers/base/platform.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)
diff mbox

Patch

diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index eee48c49f5de..9106f3046569 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -362,9 +362,7 @@  int platform_device_add(struct platform_device *pdev)

 	while (--i >= 0) {
 		struct resource *r = &pdev->resource[i];
-		unsigned long type = resource_type(r);
-
-		if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
+		if (r->parent)
 			release_resource(r);
 	}

@@ -395,9 +393,7 @@  void platform_device_del(struct platform_device *pdev)

 		for (i = 0; i < pdev->num_resources; i++) {
 			struct resource *r = &pdev->resource[i];
-			unsigned long type = resource_type(r);
-
-			if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
+			if (r->parent)
 				release_resource(r);
 		}
 	}