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 0916D218DC6; Wed, 4 Dec 2024 17:03:42 +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=1733331823; cv=none; b=RvAuLPZXd/1JwYXuz09LkASzbG3kY18tsp22ncAOlR0tqcM5Ul0+42vzHY+aL8pUZuvg+jao4fcsPnUbGVqV4FHk4XP7Y1xrM3NkleiYaifrjGt9gqOzIP/sYQjutCcy8K53LQHm0iDlDzLd6Zjo8Po1TH1+U64aDNsQziNlJR8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733331823; c=relaxed/simple; bh=yuHaRE1iv1c9h/Pp45HxXM5iJTa3nhKlWYuQeRowhbg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ufHQuEkOVPR5+G/UwHizKorciv20EBYscTp+299WUG3wZhghf6w3siGYwQ/VhzlLeIjG6WR/5NhwcJaQ7SSmKISthjxxhfOKeRNtCq/j9Y5Co4bITVuIYqHoQEs6Z5/3hyhfTo46tF3CXbQv0GmZrK8cUiR3hFnqu7BzFAKEagM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Zd7ZiwgC; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Zd7ZiwgC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 658E0C4CED1; Wed, 4 Dec 2024 17:03:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1733331822; bh=yuHaRE1iv1c9h/Pp45HxXM5iJTa3nhKlWYuQeRowhbg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Zd7ZiwgCyS53dMy10iRYLq7QZeg1v/l8go2/Bdjyq6Umqcy4VqnjVARNHnRDsdJIn tuVKsKlYXRrTkxzT3jwiy9Eu4SMXlka72V3TZi8AqdzpiaASujkSDOGpleqfkgbK1O 1aZ/3Dz/wMkhZhUc/8qJCWiT0B8kWK+C75Aaw07cMn4ViKrUeRntVk6GG4Qtj3V9He QJAO8KUrbH4F5B/eVSXashe+bO7TBMrhin6yChzEWYdUBwO3ZYooK8JAyB0c4Ha89Z I5VnS6Xs0xMeLKeSdm+b/jhj5BVOXJXfhdJzZ4+DE+dEbFQq2bPOEoTjZdXfgkRY05 rDm4UltEexjog== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Yi Yang , Dave Jiang , Ira Weiny , Sasha Levin , dan.j.williams@intel.com, vishal.l.verma@intel.com, nvdimm@lists.linux.dev Subject: [PATCH AUTOSEL 5.4 7/7] nvdimm: rectify the illogical code within nd_dax_probe() Date: Wed, 4 Dec 2024 10:52:12 -0500 Message-ID: <20241204155213.2215170-7-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20241204155213.2215170-1-sashal@kernel.org> References: <20241204155213.2215170-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 5.4.286 Content-Transfer-Encoding: 8bit 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 6d22b0f83b3b0..c882534dbe84c 100644 --- a/drivers/nvdimm/dax_devs.c +++ b/drivers/nvdimm/dax_devs.c @@ -113,12 +113,12 @@ 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 ee5c04070ef91..23d011b01fa61 100644 --- a/drivers/nvdimm/nd.h +++ b/drivers/nvdimm/nd.h @@ -326,6 +326,13 @@ 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(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