[PATCH v6 5/6] PCI/sysfs: Only show value when driver_override is not NULL

From: "Krzysztof Wilczyński" <kw@linux.com>
To: Bjorn Helgaas <bhelgaas@google.com>
Cc: Logan Gunthorpe <logang@deltatee.com>,
	Joe Perches <joe@perches.com>,
	"Oliver O'Halloran" <oohall@gmail.com>,
	Michael Ellerman <mpe@ellerman.id.au>,
	Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Paul Mackerras <paulus@samba.org>,
	Tyrel Datwyler <tyreld@linux.ibm.com>,
	Russell Currey <ruscur@russell.cc>,
	Kurt Schwemmer <kurt.schwemmer@microsemi.com>,
	Vidya Sagar <vidyas@nvidia.com>,
	Xiongfeng Wang <wangxiongfeng2@huawei.com>,
	linux-pci@vger.kernel.org
Subject: [PATCH v6 5/6] PCI/sysfs: Only show value when driver_override is not NULL
Date: Thu,  3 Jun 2021 00:01:11 +0000	[thread overview]
Message-ID: <20210603000112.703037-6-kw@linux.com> (raw)
In-Reply-To: <20210603000112.703037-1-kw@linux.com>

Only expose the value of the "driver_override" variable through the
corresponding sysfs object when a value is actually set.

Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
---
 drivers/pci/pci-sysfs.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 5d63df7c1820..4e9f582ca10f 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -580,10 +580,11 @@ static ssize_t driver_override_show(struct device *dev,
 				    struct device_attribute *attr, char *buf)
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
-	ssize_t len;
+	ssize_t len = 0;
 
 	device_lock(dev);
-	len = sysfs_emit(buf, "%s\n", pdev->driver_override);
+	if (pdev->driver_override)
+		len = sysfs_emit(buf, "%s\n", pdev->driver_override);
 	device_unlock(dev);
 	return len;
 }
-- 
2.31.1

