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Date:   Tue, 11 Jul 2023 08:22:33 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Hannes Reinecke <hare@suse.de>
Cc:     Christoph Hellwig <hch@lst.de>, Jaegeuk Kim <jaegeuk@kernel.org>,
        chao@kernel.org, linux-f2fs-devel@lists.sourceforge.net,
        linux-block@vger.kernel.org
Subject: Re: [PATCH] f2fs: don't reopen the main block device in
 f2fs_scan_devices
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References: <20230707094028.107898-1-hch@lst.de> <ZKx2jVONy35B0/S1@google.com> <20230711050101.GA19128@lst.de> <63766a54-54db-20a7-ba2f-d31fd230623d@suse.de>
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On Tue, Jul 11, 2023 at 08:19:50AM +0200, Hannes Reinecke wrote:
>>     	for (i = 0; i < sbi->s_ndevs; i++) {
>> -		blkdev_put(FDEV(i).bdev, sbi->sb->s_type);
>> +		if (i > 0)
>> +			blkdev_put(FDEV(i).bdev, sbi->sb->s_type);
> You could have started the loop at '1', and avoid the curious 'if' clause 

That's what the previous version did, which caused a NULL pointer
dereference discussed in this thread, as well as a compile error for
non-zoned builds..