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Date:   Tue, 24 Aug 2021 16:12:48 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Maor Gottlieb <maorg@nvidia.com>
Cc:     dledford@redhat.com, hch@infradead.org, leonro@nvidia.com,
        aelior@marvell.com, daniel@ffwll.ch, airlied@linux.ie,
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        maarten.lankhorst@linux.intel.com, mripard@kernel.org,
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Subject: Re: [PATCH rdma-next v4 2/3] lib/scatterlist: Fix wrong update of
 orig_nents
Message-ID: <20210824191248.GY1721383@nvidia.com>
References: <20210824142531.3877007-1-maorg@nvidia.com>
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On Tue, Aug 24, 2021 at 05:25:30PM +0300, Maor Gottlieb wrote:
> @@ -514,11 +531,13 @@ struct scatterlist *sg_alloc_append_table_from_pages(struct sg_table *sgt,
>  		offset = 0;
>  		cur_page = j;
>  	}
> -	sgt->nents += added_nents;
> +	sgt_append->sgt.nents += added_nents;
> +	sgt_append->sgt.orig_nents = sgt_append->sgt.nents;
> +	sgt_append->prv = s;

Why is nents being touched here?

Shouldn't it just be

    sgt_append->sgt.orig_nents += added_nents; 
    sgt_append->prv = s;

?

Let me know I can fix it

Jason