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 7D5AB22655E; Thu, 12 Dec 2024 15:46:48 +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=1734018408; cv=none; b=NJYMuu4kFPHGhYbjhfTBXmMR0N9AvW55KCzCZQLdVOMV7FV/krRUrUg8/1Z3UGAPQ5THiSS8zJWvjXJRxzqNQfH2denQjbF3Wt5hf4OGW2jcTzomSi+wZgSmPrcnVrz46dlgA97FUikgDi3YfBiYz8JieyIXoOjn3+TgIbFSrdQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734018408; c=relaxed/simple; bh=SgTnMuJhIhk907cegzNkKUDzEXouJCkt/nfKa864JrU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=FgoeaK+4Qxjt9Mhsk1RVz/KgHCABzrvy9fdy1me/7l2NVippeKZfSVopk9VQY16KYgM+LXWcT3PncMAXQZnN0TBb81c/M8jsh2M6CUsV/95ldwv+VHHfTG9Zu9Jk+1DWE2AWX0a3eYzL0XA52NEdsaVvJB7sZd9LY4qTRPnnSuw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=RHrb2tYB; 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="RHrb2tYB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9D77DC4CED4; Thu, 12 Dec 2024 15:46:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1734018408; bh=SgTnMuJhIhk907cegzNkKUDzEXouJCkt/nfKa864JrU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RHrb2tYBnUToxAzE7PXcgghBsoaBeiE1XE9IFBS3oXkTBVUYF6sPhyIVF1OP2hrk+ n4/k9CvGpgRFm+73TSMJwXKvvhcQ3BhC2ppZgjD85GZgMbiTEvoVgRzSqaBZFEKOiS Hi6WbS1uRDoZQChNk9SLzMWGyc0t0udCa9SVzieY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yi Yang , Dave Jiang , Ira Weiny , Sasha Levin Subject: [PATCH 6.6 284/356] nvdimm: rectify the illogical code within nd_dax_probe() Date: Thu, 12 Dec 2024 16:00:03 +0100 Message-ID: <20241212144255.799431050@linuxfoundation.org> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20241212144244.601729511@linuxfoundation.org> References: <20241212144244.601729511@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 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yi Yang [ Upstream commit b61352101470f8b68c98af674e187cfaa7c43504 ] When nd_dax is NULL, nd_pfn is consequently NULL as well. Nevertheless, it is inadvisable to perform pointer arithmetic or address-taking on a NULL pointer. Introduce the nd_dax_devinit() function to enhance the code's logic and improve its readability. Signed-off-by: Yi Yang Reviewed-by: Dave Jiang Link: https://patch.msgid.link/20241108085526.527957-1-yiyang13@huawei.com Signed-off-by: Ira Weiny Signed-off-by: Sasha Levin --- drivers/nvdimm/dax_devs.c | 4 ++-- drivers/nvdimm/nd.h | 7 +++++++ 2 files changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/nvdimm/dax_devs.c b/drivers/nvdimm/dax_devs.c index 3bd61f2457885..cfafe1fa77bab 100644 --- a/drivers/nvdimm/dax_devs.c +++ b/drivers/nvdimm/dax_devs.c @@ -106,12 +106,12 @@ int nd_dax_probe(struct device *dev, struct nd_namespace_common *ndns) nvdimm_bus_lock(&ndns->dev); nd_dax = nd_dax_alloc(nd_region); - nd_pfn = &nd_dax->nd_pfn; - dax_dev = nd_pfn_devinit(nd_pfn, ndns); + dax_dev = nd_dax_devinit(nd_dax, ndns); nvdimm_bus_unlock(&ndns->dev); if (!dax_dev) return -ENOMEM; pfn_sb = devm_kmalloc(dev, sizeof(*pfn_sb), GFP_KERNEL); + nd_pfn = &nd_dax->nd_pfn; nd_pfn->pfn_sb = pfn_sb; rc = nd_pfn_validate(nd_pfn, DAX_SIG); dev_dbg(dev, "dax: %s\n", rc == 0 ? dev_name(dax_dev) : ""); diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h index e8b9d27dbb3c3..12774334273c1 100644 --- a/drivers/nvdimm/nd.h +++ b/drivers/nvdimm/nd.h @@ -601,6 +601,13 @@ struct nd_dax *to_nd_dax(struct device *dev); int nd_dax_probe(struct device *dev, struct nd_namespace_common *ndns); bool is_nd_dax(const struct device *dev); struct device *nd_dax_create(struct nd_region *nd_region); +static inline struct device *nd_dax_devinit(struct nd_dax *nd_dax, + struct nd_namespace_common *ndns) +{ + if (!nd_dax) + return NULL; + return nd_pfn_devinit(&nd_dax->nd_pfn, ndns); +} #else static inline int nd_dax_probe(struct device *dev, struct nd_namespace_common *ndns) -- 2.43.0