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 0E827211493; Thu, 12 Dec 2024 17:50:25 +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=1734025825; cv=none; b=XvhLXc3+0PuUEwTkUH0bFL3uu9sGHXLifq9uS+8PgBNVs0xOZBB7CViupmJ4S6jKR/GpLT3EMIAzDQYk5T2YFrGJOESXRdL9PkLwu+TnuHXzKaHlglNUpPhsXK/IWGRqAoHhdotzRBE5/y/LRHKMUxi/F+qcOU9CWFLPXf/m408= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734025825; c=relaxed/simple; bh=5E0AShuCDBPho634uTbJHPz7/aWgOdOCPP1FQaU5G7c=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=sWwj94qzDo6i+0pY/jcm8yuEMbdlwA20u+yxEdX7iJL5kIcep3FMb0TTiHd3K9iJsPmNQmZune0kDxPsP2ZkokEWvU4QpcrmjOmLnruSZry4E3jrU0O1HTg6i6TIRmyvHIHru1WmUNdPzoFmtUcukKME9sGzkQBQmO8JeP6eQIE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=U38gOIB1; 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="U38gOIB1" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 87D7BC4CECE; Thu, 12 Dec 2024 17:50:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1734025824; bh=5E0AShuCDBPho634uTbJHPz7/aWgOdOCPP1FQaU5G7c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=U38gOIB1eBl0uoIXlSzTgAYQ6a9Icgi6XlOM/AlF5GS5/t/O9jldPcbjStaqIIodq vGFGa+TgPL9IEl4VqPzoY1l3r0QuzRiQBNoiIZ2IQCROlluTPtIjgWPrmSA1L87CMZ lj0fpyakUWok2LrKYHfaDFmUi4FCUkulO+RY82lA= 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 5.4 299/321] nvdimm: rectify the illogical code within nd_dax_probe() Date: Thu, 12 Dec 2024 16:03:37 +0100 Message-ID: <20241212144241.787868375@linuxfoundation.org> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20241212144229.291682835@linuxfoundation.org> References: <20241212144229.291682835@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 5.4-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 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