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Date:   Wed, 11 Sep 2019 12:35:18 +0200
From:   Joerg Roedel <joro@8bytes.org>
To:     Lu Baolu <baolu.lu@linux.intel.com>
Cc:     Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
        David Woodhouse <dwmw2@infradead.org>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Christoph Hellwig <hch@lst.de>, ashok.raj@intel.com,
        jacob.jun.pan@intel.com, alan.cox@intel.com, kevin.tian@intel.com,
        mika.westerberg@linux.intel.com, Ingo Molnar <mingo@redhat.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        pengfei.xu@intel.com, Marek Szyprowski <m.szyprowski@samsung.com>,
        Robin Murphy <robin.murphy@arm.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Boris Ostrovsky <boris.ostrovsky@oracle.com>,
        Juergen Gross <jgross@suse.com>,
        Stefano Stabellini <sstabellini@kernel.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v9 1/5] swiotlb: Split size parameter to map/unmap APIs
Message-ID: <20190911103517.GA21988@8bytes.org>
References: <20190906061452.30791-1-baolu.lu@linux.intel.com>
 <20190906061452.30791-2-baolu.lu@linux.intel.com>
 <20190910151544.GA7585@char.us.oracle.com>
 <0b939480-cb99-46fe-374e-a31441d21486@linux.intel.com>
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On Wed, Sep 11, 2019 at 02:16:07PM +0800, Lu Baolu wrote:
> How about this change?
> 
> diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
> index 89066efa3840..22a7848caca3 100644
> --- a/kernel/dma/swiotlb.c
> +++ b/kernel/dma/swiotlb.c
> @@ -466,8 +466,11 @@ phys_addr_t swiotlb_tbl_map_single(struct device
> *hwdev,
>                 pr_warn_once("%s is active and system is using DMA bounce
> buffers\n",
>                              sme_active() ? "SME" : "SEV");
> 
> -       if (WARN_ON(mapping_size > alloc_size))
> +       if (mapping_size > alloc_size) {
> +               dev_warn_once(hwdev, "Invalid sizes (mapping: %zd bytes,
> alloc: %zd bytes)",
> +                             mapping_size, alloc_size);
>                 return (phys_addr_t)DMA_MAPPING_ERROR;
> +       }
> 
>         mask = dma_get_seg_boundary(hwdev);
> 
> @@ -584,9 +587,6 @@ void swiotlb_tbl_unmap_single(struct device *hwdev,
> phys_addr_t tlb_addr,
>         int index = (tlb_addr - io_tlb_start) >> IO_TLB_SHIFT;
>         phys_addr_t orig_addr = io_tlb_orig_addr[index];
> 
> -       if (WARN_ON(mapping_size > alloc_size))
> -               return;
> -
>         /*
>          * First, sync the memory before unmapping the entry
>          */

Folded that into the commit, thanks Lu Baolu.