Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <c22de8df-0599-0a86-146a-267f576f5500@deltatee.com>
Date:   Tue, 24 May 2022 09:55:51 -0600
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101
 Thunderbird/91.8.0
Content-Language: en-CA
To:     Donald Buczek <buczek@molgen.mpg.de>, linux-kernel@vger.kernel.org,
        linux-raid@vger.kernel.org, Song Liu <song@kernel.org>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Guoqing Jiang <guoqing.jiang@linux.dev>,
        Xiao Ni <xni@redhat.com>, Stephen Bates <sbates@raithlin.com>,
        Martin Oliveira <Martin.Oliveira@eideticom.com>,
        David Sloan <David.Sloan@eideticom.com>
References: <20220519191311.17119-1-logang@deltatee.com>
 <20220519191311.17119-13-logang@deltatee.com>
 <571344e2-6e43-a72f-bd12-04d650e669fd@molgen.mpg.de>
From:   Logan Gunthorpe <logang@deltatee.com>
In-Reply-To: <571344e2-6e43-a72f-bd12-04d650e669fd@molgen.mpg.de>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Subject: Re: [PATCH v1 12/15] md/raid5-cache: Add RCU protection to conf->log
 accesses
Precedence: bulk


On 2022-05-22 01:32, Donald Buczek wrote:
>>   /*
>> @@ -703,7 +720,7 @@ static void r5c_disable_writeback_async(struct work_struct *work)
>>   
>>   	/* wait superblock change before suspend */
>>   	wait_event(mddev->sb_wait,
>> -		   conf->log == NULL ||
>> +		   rcu_access_pointer(conf->log) ||
> 
> Reversed condition?
> 
> I think, some examples in Documentation/RCU/Design/Requirements/Requirements.rst are reversed, too.

Oops. Nice Catch!

Thanks,

Logan