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Date:   Tue, 16 Mar 2021 09:00:52 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Logan Gunthorpe <logang@deltatee.com>
Cc:     linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org,
        linux-block@vger.kernel.org, linux-pci@vger.kernel.org,
        linux-mm@kvack.org, iommu@lists.linux-foundation.org,
        Stephen Bates <sbates@raithlin.com>,
        Christoph Hellwig <hch@lst.de>,
        Dan Williams <dan.j.williams@intel.com>,
        Jason Gunthorpe <jgg@ziepe.ca>,
        Christian =?iso-8859-1?Q?K=F6nig?= <christian.koenig@amd.com>,
        Ira Weiny <iweiny@intel.com>,
        John Hubbard <jhubbard@nvidia.com>,
        Don Dutile <ddutile@redhat.com>,
        Matthew Wilcox <willy@infradead.org>,
        Daniel Vetter <daniel.vetter@ffwll.ch>,
        Jakowski Andrzej <andrzej.jakowski@intel.com>,
        Minturn Dave B <dave.b.minturn@intel.com>,
        Jason Ekstrand <jason@jlekstrand.net>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Xiong Jianxin <jianxin.xiong@intel.com>
Subject: Re: [RFC PATCH v2 09/11] block: Add BLK_STS_P2PDMA
Message-ID: <20210316080051.GD15949@lst.de>
References: <20210311233142.7900-1-logang@deltatee.com> <20210311233142.7900-10-logang@deltatee.com>
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On Thu, Mar 11, 2021 at 04:31:39PM -0700, Logan Gunthorpe wrote:
> Create a specific error code for when P2PDMA pages are passed to a block
> devices that cannot map them (due to no IOMMU support or ACS protections).
> 
> This makes request errors in these cases more informative of as to what
> caused the error.

I really don't think we should bother with a specific error code here,
we don't add a new status for every single possible logic error in the
caller.