This is a note to let you know that I've just added the patch titled
fpga: bridge: properly initialize bridge device before populating children
to the 6.2-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
fpga-bridge-properly-initialize-bridge-device-before-populating-children.patch
and it can be found in the queue-6.2 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From dc70eb868b9cd2ca01313e5a394e6ea001d513e9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Alexis=20Lothor=C3=A9?= <alexis.lothore@xxxxxxxxxxx>
Date: Tue, 4 Apr 2023 15:31:02 +0200
Subject: fpga: bridge: properly initialize bridge device before populating children
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From: Alexis Lothoré <alexis.lothore@xxxxxxxxxxx>
commit dc70eb868b9cd2ca01313e5a394e6ea001d513e9 upstream.
The current code path can lead to warnings because of uninitialized device,
which contains, as a consequence, uninitialized kobject. The uninitialized
device is passed to of_platform_populate, which will at some point, while
creating child device, try to get a reference on uninitialized parent,
resulting in the following warning:
kobject: '(null)' ((ptrval)): is not initialized, yet kobject_get() is
being called.
The warning is observed after migrating a kernel 5.10.x to 6.1.x.
Reverting commit 0d70af3c2530 ("fpga: bridge: Use standard dev_release for
class driver") seems to remove the warning.
This commit aggregates device_initialize() and device_add() into
device_register() but this new call is done AFTER of_platform_populate
Fixes: 0d70af3c2530 ("fpga: bridge: Use standard dev_release for class driver")
Signed-off-by: Alexis Lothoré <alexis.lothore@xxxxxxxxxxx>
Acked-by: Xu Yilun <yilun.xu@xxxxxxxxx>
Link: https://lore.kernel.org/r/20230404133102.2837535-2-alexis.lothore@xxxxxxxxxxx
Signed-off-by: Xu Yilun <yilun.xu@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/fpga/fpga-bridge.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/fpga/fpga-bridge.c
+++ b/drivers/fpga/fpga-bridge.c
@@ -360,7 +360,6 @@ fpga_bridge_register(struct device *pare
bridge->dev.parent = parent;
bridge->dev.of_node = parent->of_node;
bridge->dev.id = id;
- of_platform_populate(bridge->dev.of_node, NULL, NULL, &bridge->dev);
ret = dev_set_name(&bridge->dev, "br%d", id);
if (ret)
@@ -372,6 +371,8 @@ fpga_bridge_register(struct device *pare
return ERR_PTR(ret);
}
+ of_platform_populate(bridge->dev.of_node, NULL, NULL, &bridge->dev);
+
return bridge;
error_device:
Patches currently in stable-queue which might be from alexis.lothore@xxxxxxxxxxx are
queue-6.2/fpga-bridge-properly-initialize-bridge-device-before-populating-children.patch
