From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 335AD74438; Mon, 8 Apr 2024 14:06:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712585180; cv=none; b=oURbS+CzpqUVNoRCevqg0lKqjTCsRxh8VnhiUE8wrPy53xZ8yf48Qa8RjVGdX3mnkAMDCVVpZf8D9WNkf34IM3aq19v/0gnPeR210gDpW49OZpdM4bKrZ/Q45WIyASjmuQKKXfgyGTHL8OgzUUWOMn/JRG9qB0qcKj5OqPwtIaY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712585180; c=relaxed/simple; bh=/lPDgzCmyRdPVk0nIu1gokLXiuwvGgpMhYJDFNl9WxQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ThxkhN4mjttaNj+mfUt41zmdLUlxni+JMEbl2pvLu1lYLNU0QHxAgvEVzdI3KexuZwUJ/Y+pHAUsEWGlmTyC2bIKu/gNtUAALaW1fYi8gfi0semNWz6bPp5keWdk997n5hyY07jKZOaeFP1p5nd8cYyxsLtjAWzOMdXHuw5mr04= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Nu3rOALm; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Nu3rOALm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A86F9C433F1; Mon, 8 Apr 2024 14:06:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1712585180; bh=/lPDgzCmyRdPVk0nIu1gokLXiuwvGgpMhYJDFNl9WxQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Nu3rOALmSygV88A5gY1V1qZhuEDL0fM0CFwMmP2T/K20yHDICfFcKjgdGdfmbc3br JQuD1SuwJsNNT8Zu8Wy0W+1cOAxcvLBag9CL1ygakQj7W38tlxGG+38UaOBVzdtSDV maD+HQF1nRG7GkrSZnggfdQwuGirNo/tLws6EPyw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Herve Codina , Saravana Kannan , Luca Ceresoli , Nuno Sa , Rob Herring Subject: [PATCH 5.15 680/690] of: dynamic: Synchronize of_changeset_destroy() with the devlink removals Date: Mon, 8 Apr 2024 14:59:06 +0200 Message-ID: <20240408125424.362888304@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240408125359.506372836@linuxfoundation.org> References: <20240408125359.506372836@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Herve Codina commit 8917e7385346bd6584890ed362985c219fe6ae84 upstream. In the following sequence: 1) of_platform_depopulate() 2) of_overlay_remove() During the step 1, devices are destroyed and devlinks are removed. During the step 2, OF nodes are destroyed but __of_changeset_entry_destroy() can raise warnings related to missing of_node_put(): ERROR: memory leak, expected refcount 1 instead of 2 ... Indeed, during the devlink removals performed at step 1, the removal itself releasing the device (and the attached of_node) is done by a job queued in a workqueue and so, it is done asynchronously with respect to function calls. When the warning is present, of_node_put() will be called but wrongly too late from the workqueue job. In order to be sure that any ongoing devlink removals are done before the of_node destruction, synchronize the of_changeset_destroy() with the devlink removals. Fixes: 80dd33cf72d1 ("drivers: base: Fix device link removal") Cc: stable@vger.kernel.org Signed-off-by: Herve Codina Reviewed-by: Saravana Kannan Tested-by: Luca Ceresoli Reviewed-by: Nuno Sa Link: https://lore.kernel.org/r/20240325152140.198219-3-herve.codina@bootlin.com Signed-off-by: Rob Herring Signed-off-by: Greg Kroah-Hartman --- drivers/of/dynamic.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) --- a/drivers/of/dynamic.c +++ b/drivers/of/dynamic.c @@ -9,6 +9,7 @@ #define pr_fmt(fmt) "OF: " fmt +#include #include #include #include @@ -678,6 +679,17 @@ void of_changeset_destroy(struct of_chan { struct of_changeset_entry *ce, *cen; + /* + * When a device is deleted, the device links to/from it are also queued + * for deletion. Until these device links are freed, the devices + * themselves aren't freed. If the device being deleted is due to an + * overlay change, this device might be holding a reference to a device + * node that will be freed. So, wait until all already pending device + * links are deleted before freeing a device node. This ensures we don't + * free any device node that has a non-zero reference count. + */ + device_link_wait_removal(); + list_for_each_entry_safe_reverse(ce, cen, &ocs->entries, node) __of_changeset_entry_destroy(ce); }