Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Subject: Re: [PATCH 6/9] s390/block/dasd_genhd: add error handling support for
 add_disk()
From:   =?UTF-8?Q?Jan_H=c3=b6ppner?= <hoeppner@linux.ibm.com>
To:     Luis Chamberlain <mcgrof@kernel.org>, axboe@kernel.dk,
        gregkh@linuxfoundation.org, chaitanya.kulkarni@wdc.com,
        atulgopinathan@gmail.com, hare@suse.de, maximlevitsky@gmail.com,
        oakad@yahoo.com, ulf.hansson@linaro.org, colin.king@canonical.com,
        shubhankarvk@gmail.com, baijiaju1990@gmail.com, trix@redhat.com,
        dongsheng.yang@easystack.cn, ceph-devel@vger.kernel.org,
        miquel.raynal@bootlin.com, richard@nod.at, vigneshr@ti.com,
        sth@linux.ibm.com, hca@linux.ibm.com, gor@linux.ibm.com,
        borntraeger@de.ibm.com, oberpar@linux.ibm.com, tj@kernel.org
Cc:     linux-s390@vger.kernel.org, linux-mtd@lists.infradead.org,
        linux-mmc@vger.kernel.org, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20210902174105.2418771-1-mcgrof@kernel.org>
 <20210902174105.2418771-7-mcgrof@kernel.org>
 <d6140e40-a472-e732-9893-99e1839b717e@linux.ibm.com>
Message-ID: <f24da7d5-0b67-fa24-862f-0b27a2ab502c@linux.ibm.com>
Date:   Mon, 13 Sep 2021 14:19:38 +0200
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101
 Thunderbird/78.11.0
MIME-Version: 1.0
In-Reply-To: <d6140e40-a472-e732-9893-99e1839b717e@linux.ibm.com>
Content-Type: text/plain; charset=utf-8
Content-Language: en-US
Content-Transfer-Encoding: 8bit
Precedence: bulk

On 13/09/2021 10:17, Jan Höppner wrote:
> On 02/09/2021 19:41, Luis Chamberlain wrote:
>> We never checked for errors on add_disk() as this function
>> returned void. Now that this is fixed, use the shiny new
>> error handling.
>>
>> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
>> ---
>>  drivers/s390/block/dasd_genhd.c | 8 ++++++--
>>  1 file changed, 6 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/s390/block/dasd_genhd.c b/drivers/s390/block/dasd_genhd.c
>> index fa966e0db6ca..ba07022283bc 100644
>> --- a/drivers/s390/block/dasd_genhd.c
>> +++ b/drivers/s390/block/dasd_genhd.c
>> @@ -33,7 +33,7 @@ int dasd_gendisk_alloc(struct dasd_block *block)
>>  {
>>  	struct gendisk *gdp;
>>  	struct dasd_device *base;
>> -	int len;
>> +	int len, rc;
>>  
>>  	/* Make sure the minor for this device exists. */
>>  	base = block->base;
>> @@ -79,7 +79,11 @@ int dasd_gendisk_alloc(struct dasd_block *block)
>>  	dasd_add_link_to_gendisk(gdp, base);
>>  	block->gdp = gdp;
>>  	set_capacity(block->gdp, 0);
>> -	device_add_disk(&base->cdev->dev, block->gdp, NULL);
>> +
>> +	rc = device_add_disk(&base->cdev->dev, block->gdp, NULL);
>> +	if (rc)
>> +		return rc;
>> +
> 
> I think, just like with some of the other changes, there is some
> cleanup required before returning. I'll prepare a patch and
> come back to you.
> 

It's actually just one call that is required. The patch should
look like this:

diff --git a/drivers/s390/block/dasd_genhd.c b/drivers/s390/block/dasd_genhd.c
index fa966e0db6ca..80673dbfb1f9 100644
--- a/drivers/s390/block/dasd_genhd.c
+++ b/drivers/s390/block/dasd_genhd.c
@@ -33,7 +33,7 @@ int dasd_gendisk_alloc(struct dasd_block *block)
 {
        struct gendisk *gdp;
        struct dasd_device *base;
-       int len;
+       int len, rc;
 
        /* Make sure the minor for this device exists. */
        base = block->base;
@@ -79,7 +79,13 @@ int dasd_gendisk_alloc(struct dasd_block *block)
        dasd_add_link_to_gendisk(gdp, base);
        block->gdp = gdp;
        set_capacity(block->gdp, 0);
-       device_add_disk(&base->cdev->dev, block->gdp, NULL);
+
+       rc = device_add_disk(&base->cdev->dev, block->gdp, NULL);
+       if (rc) {
+               dasd_gendisk_free(block);
+               return rc;
+       }
+
        return 0;
 }

regards,
Jan