RE: [PATCH] IB/core: fix memory leak on ah on error return path

From: Parav Pandit
Date: Tue Aug 08 2017 - 15:48:12 EST


Hi,

I need to top post because comments are unrelated to past discussion.

rdma_ah_retrieve_dmac() can never fail for RoCE as its returning pointer from structure ah_attr.
Provider driver doesn't need to check for null pointer as ib/core would never call provider if it's not RoCE provider.
So this memory leak only exist in theory.

When its null, driver should WARN_ON/BUG_ON in extreme case, but that's not necessary either.

I have patch is progress under internal review that does nice small cleanup in many provider drivers that eliminates the check completely.
Waiting for Moni to finish the review.

Parav

> -----Original Message-----
> From: linux-rdma-owner@xxxxxxxxxxxxxxx [mailto:linux-rdma-
> owner@xxxxxxxxxxxxxxx] On Behalf Of Johannes Thumshirn
> Sent: Tuesday, August 08, 2017 7:59 AM
> To: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> Cc: Lijun Ou <oulijun@xxxxxxxxxx>; Wei Hu <xavier.huwei@xxxxxxxxxx>;
> Doug Ledford <dledford@xxxxxxxxxx>; Sean Hefty <sean.hefty@xxxxxxxxx>;
> Hal Rosenstock <hal.rosenstock@xxxxxxxxx>; linux-rdma@xxxxxxxxxxxxxxx;
> kernel-janitors@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH] IB/core: fix memory leak on ah on error return path
>
> On Tue, Aug 08, 2017 at 11:28:16AM +0100, Colin Ian King wrote:
> > I was using the same subject start as the patch that introduced the
> > memory leak and touched the same portion of code. I can resend if necessary.
>
> I think having the hns prefix makes it clearer, as the patch doesn't touch IB core
> code but hns code. The reference to the patch which introduced the leak is given
> byu the fixes line.
>
> Thanks,
> Johannes
>
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> Johannes Thumshirn Storage
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