From mboxrd@z Thu Jan  1 00:00:00 1970
From: Hannes Reinecke <hare@suse.de>
Subject: Re: [PATCH] dm-mpath: Track invalid map_context
Date: Mon, 19 Mar 2012 16:36:27 +0100
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On 03/19/2012 04:20 PM, Alasdair G Kergon wrote:
> On Mon, Mar 19, 2012 at 04:15:28PM +0100, Hannes Reinecke wrote:
>> -	if (r < 0 || r =3D=3D DM_MAPIO_REQUEUE)
>> +	if (r < 0 || r =3D=3D DM_MAPIO_REQUEUE) {
>>  		mempool_free(mpio, m->mpio_pool);
>> +		map_context->ptr =3D NULL;
>> +	}
> =

> What about the other places that do mempool_free() ?
> Should they clear it too?
> =

Hmm. Probably. It's not strictly speaking required as the other
places will never re-use the context pointer.
But for consistencies sake you are correct.
Will be updating the patch.

> Is it better to swap the statement order - clear it *before*
> freeing i
> =

Doubt that should be required.
I would hope that the map_context pointer is protected by
appropriate locks.

Cheers,

Hannes
-- =

Dr. Hannes Reinecke		      zSeries & Storage
hare@suse.de			      +49 911 74053 688
SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 N=FCrnberg
GF: J. Hawn, J. Guild, F. Imend=F6rffer, HRB 16746 (AG N=FCrnberg)