[dm-devel] [PATCH 3/5] multipathd: add reclear_pp_from_mpp in ev_remove_path

[lixiaokeng]

Hi Martin:
   I test this in 0.8.4 without your patch series . I have review the
code with your patch series and I think this problem will be solved.
But I have another question.
ev_remove_path
	->__setup_multipath
		->update_multipath_strings
			->update_multipath_table
				->update_pathvec_from_dm
					->store_path
When multipathd del path xxx(such as sde) and multipath -v2 are
executed simultaneously, will the path(sde) deleted be stored to pathvec
again? In my opinion, sde is't delete in pathvec and in disassembel_map
sde will be stored to mpp->pg. When update_pathvec_from_dm, sde will be
stored again.

On 2020/8/19 0:36, Martin Wilck wrote:
> On Tue, 2020-08-18 at 21:08 +0800, lixiaokeng wrote:
>> Add reclear_pp_from_mpp in ev_remove_path to make sure that pp is
>> cleared in mpp.
>>
>> When multipathd del path xxx, multipathd -v2, multipathd add path xxx
>> and multipath -U
>> dm-x are executed simultaneously, multipath -U dm-x will case
>> coredump.
>>
>> The reason is that there are two paths with same dev_t in dm_table.
>> The process
>> is as follows:
> 
> Thanks for the report.
> 
> With which code have you tested this? I have reason to believe that 
> it would behave differently with my last patch series (in particular,
> part V "removed path handling") applied. I'm not sure if my series
> would fix the issue, but it would probably need a different fix.
> 
> Regards,
> Martin
> 
> 
> 
> .
>