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Subject: Re: [f2fs-dev] [PATCH V2] f2fs: Avoid double lock for cp_rwsem during
 checkpoint
To:     Dan Carpenter <dan.carpenter@oracle.com>
Cc:     Markus Elfring <Markus.Elfring@web.de>,
        linux-f2fs-devel@lists.sourceforge.net,
        Jaegeuk Kim <jaegeuk@kernel.org>, Chao Yu <yuchao0@huawei.com>,
        linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org
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 <20200429124402.GP2014@kadam>
From:   Sayali Lokhande <sayalil@codeaurora.org>
Message-ID: <71c37cbb-03cd-134f-8b68-cf06bfa05317@codeaurora.org>
Date:   Wed, 29 Apr 2020 22:22:58 +0530
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On 4/29/2020 6:14 PM, Dan Carpenter wrote:
> On Wed, Apr 29, 2020 at 10:28:36AM +0530, Sayali Lokhande wrote:
>> Hi Markus
>>
>> On 4/27/2020 4:08 PM, Markus Elfring wrote:
>>>> … This results in deadlock as
>>>> iput() tries to hold cp_rwsem, which is already held at the
>>>> beginning by checkpoint->block_operations().
>>> Will another imperative wording become helpful besides the provided information
>>> for this change description?
>>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/submitting-patches.rst?id=6a8b55ed4056ea5559ebe4f6a4b247f627870d4c#n151
>>>
>>> Would you like to add the tag “Fixes” because of adjustments
>>> for the data synchronisation?
>> I couldn't find any past commit which suits to be added under "Fixes" here.
>> Let me know if you have any other comment.
> This looks really old.  Maybe commit 399368372ed9 ("f2fs: introduce a
> new global lock scheme")?
Yes. Let me update it in Fixes tag in V3 and post it. Thanks for 
pointing it.
>
> regards,
> dan carpenter
>