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Date:   Tue, 17 May 2022 11:11:02 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     John Garry <john.garry@huawei.com>
Cc:     Christoph Hellwig <hch@lst.de>, joro@8bytes.org, will@kernel.org,
        robin.murphy@arm.com, m.szyprowski@samsung.com,
        chenxiang66@hisilicon.com, thunder.leizhen@huawei.com,
        iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
        liyihang6@hisilicon.com
Subject: Re: [RFC PATCH] dma-iommu: Add iommu_dma_max_mapping_size()
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On Tue, May 17, 2022 at 10:02:00AM +0100, John Garry wrote:
> BTW, on a separate topic, I noticed that even with this change my ATA 
> devices have max_hw_sectors_kb of 32767, as opposed to 128 for SAS devices. 
> It seems that libata-scsi - specifically ata_scsi_dev_config() - doesn't 
> honour the shost max_sectors limit. I guess that is not intentional.

I don't think it is.  the libsas/libsata integration is a bit messy
sometimes..