Re: [PATCH 3/3] f2fs: prevent waiter encountering incorrect discard states

From	Chao Yu <yuchao0@huawei.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH 3/3] f2fs: prevent waiter encountering incorrect discard states
Date	2017-03-28 03:20 +0200
Message-ID	<tpNXI-8w9-15@gated-at.bofh.it> (permalink)
References	<tpzUJ-6u4-3@gated-at.bofh.it> <tpzUJ-6u4-1@gated-at.bofh.it> <tpMIi-7o5-3@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On 2017/3/28 7:56, Jaegeuk Kim wrote:
> On 03/27, Chao Yu wrote:
>> In f2fs_submit_discard_endio, we will wake up waiter before setting
>> discard command states, so waiter may use incorrect states. Change
>> the order between complete() and states setting to fix this issue.
>>
>> Signed-off-by: Chao Yu <yuchao0@huawei.com>
>> ---
>>  fs/f2fs/segment.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
>> index 57a81f9c8c14..9f9542c9fe47 100644
>> --- a/fs/f2fs/segment.c
>> +++ b/fs/f2fs/segment.c
>> @@ -717,9 +717,9 @@ static void f2fs_submit_discard_endio(struct bio *bio)
>>  {
>>  	struct discard_cmd *dc = (struct discard_cmd *)bio->bi_private;
>>  
>> -	complete(&dc->wait);
>>  	dc->error = bio->bi_error;
>>  	dc->state = D_DONE;
>> +	complete(&dc->wait);
> 
> If we set D_DONE first, the object can be released by __remove_discard_cmd()?

Yes, I think so.

Thanks,

> 
> Thanks,
> 
>>  	bio_put(bio);
>>  }
>>  
>> -- 
>> 2.8.2.295.g3f1c1d0
> 
> .
>

Thread

[PATCH 3/3] f2fs: prevent waiter encountering incorrect discard states Chao Yu <yuchao0@huawei.com> - 2017-03-27 12:20 +0200
  Re: [PATCH 3/3] f2fs: prevent waiter encountering incorrect discard  states Jaegeuk Kim <jaegeuk@kernel.org> - 2017-03-28 02:00 +0200
    Re: [PATCH 3/3] f2fs: prevent waiter encountering incorrect discard  states Chao Yu <yuchao0@huawei.com> - 2017-03-28 03:20 +0200
      Re: [PATCH 3/3] f2fs: prevent waiter encountering incorrect discard  states Chao Yu <yuchao0@huawei.com> - 2017-04-01 09:00 +0200
        Re: [PATCH 3/3] f2fs: prevent waiter encountering incorrect discard  states Jaegeuk Kim <jaegeuk@kernel.org> - 2017-04-03 19:50 +0200
          Re: [PATCH 3/3] f2fs: prevent waiter encountering incorrect discard  states Chao Yu <yuchao0@huawei.com> - 2017-04-05 12:30 +0200

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