[PATCH 2/3] nvme-multipath: cannot disconnect controller on stuck partition scan

[Hannes Reinecke]

On 10/10/24 08:16, Hannes Reinecke wrote:
> On 10/9/24 19:32, Keith Busch wrote:
>> On Wed, Oct 09, 2024 at 08:23:45AM +0200, Hannes Reinecke wrote:
>>> With my testcase _all_ paths return NS_NOT_READY during partition 
>>> scan, so
>>> I/O is constantly bounced between paths, and partition scan never 
>>> returns.
>>> Doesn't matter where you call it, it's stuck.
>>
>> Assuming you mean a differet status, like NVME_SC_INTERNAL_PATH_ERROR, I
>> can recreate a stuck scan. Let me get one more shot at fixing this by
>> suppressing the scan to another context. This one is successful in my
>> tests:
>>
>> ---
>> diff --git a/drivers/nvme/host/multipath.c 
>> b/drivers/nvme/host/multipath.c
>> index 48e7a8906d012..e1fd53ff2c0ca 100644
>> --- a/drivers/nvme/host/multipath.c
>> +++ b/drivers/nvme/host/multipath.c
>> @@ -580,6 +580,20 @@ static int nvme_add_ns_head_cdev(struct 
>> nvme_ns_head *head)
>>       return ret;
> [ .. ]
> 
> Piling workqueues on workqueues ... but anyway, I'll give it a spin.
> 
And it even works. Care to send a proper patch?
You can add my 'Tested-by:' to it, too.
Thanks for doing this.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare at suse.de                                +49 911 74053 688
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