From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="LPx1+fRX" Received: from relay8-d.mail.gandi.net (relay8-d.mail.gandi.net [IPv6:2001:4b98:dc4:8::228]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 363A810DE; Thu, 30 Nov 2023 09:41:33 -0800 (PST) Received: by mail.gandi.net (Postfix) with ESMTPA id 32A621BF206; Thu, 30 Nov 2023 17:41:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1701366091; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=YCtXOEjZA4vVhqRvZxyqSJ/sJ1S1+pskPHyTx+aj7Bo=; b=LPx1+fRXYo9UizKn96Mo1PH2HBts4hfEy67nbnAsjK2WsGwfe2AqQ1twJi1tJiOE5RZ4C5 gaSWtIScGmcLpC8O+IbgeysUdhiqvbpILR9O1//gEskk4TKHXqDP1FCYd4nJdPuRyRyAgd NSVPU2xlfSCr3WLH1Xe0uUpzvCsH6XGMUxrtfyFn/UgZniaRrDzf1gGBOCJ0OMVPehGvhO pNJAlvN8ZOLQTzremWQjjtGbH7eTtKiUNV7heBDwknRhEZfXR1k7aVESlwktB7HsdUyVFk S449nqA/ggrQQOzKd5s5rvetaK5RNG58hVkjC0PxrrJdkTx03lxYC7XAzgweNw== From: Herve Codina To: Greg Kroah-Hartman , "Rafael J. Wysocki" , Rob Herring , Frank Rowand Cc: Lizhi Hou , Max Zhen , Sonal Santan , Stefano Stabellini , Jonathan Cameron , linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, Allan Nielsen , Horatiu Vultur , Steen Hegelund , Thomas Petazzoni , Herve Codina Subject: [PATCH 2/2] of: overlay: Synchronize of_overlay_remove() with the devlink removals Date: Thu, 30 Nov 2023 18:41:09 +0100 Message-ID: <20231130174126.688486-3-herve.codina@bootlin.com> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231130174126.688486-1-herve.codina@bootlin.com> References: <20231130174126.688486-1-herve.codina@bootlin.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-GND-Sasl: herve.codina@bootlin.com 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_overlay_remove() with the devlink removals. Signed-off-by: Herve Codina --- drivers/of/overlay.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c index a9a292d6d59b..5c5f808b163e 100644 --- a/drivers/of/overlay.c +++ b/drivers/of/overlay.c @@ -1202,6 +1202,12 @@ int of_overlay_remove(int *ovcs_id) goto out; } + /* + * Wait for any ongoing device link removals before removing some of + * nodes + */ + device_link_wait_removal(); + mutex_lock(&of_mutex); ovcs = idr_find(&ovcs_idr, *ovcs_id); -- 2.42.0