linux-kernel - Re: [Xen-devel] [PATCH] Revert "swiotlb: remove SWIOTLB_MAP

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 8 Mar 2019 16:23:55 +0100
From:   Christoph Hellwig <hch@....de>
To:     Julien Grall <julien.grall@....com>
Cc:     Arnd Bergmann <arnd@...db.de>, Robin Murphy <robin.murphy@....com>,
        Juergen Gross <jgross@...e.com>,
        Stefano Stabellini <sstabellini@...nel.org>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        Mike Rapoport <rppt@...ux.ibm.com>,
        "open list:IOMMU DRIVERS" <iommu@...ts.linux-foundation.org>,
        Joerg Roedel <jroedel@...e.de>,
        xen-devel <xen-devel@...ts.xenproject.org>,
        Boris Ostrovsky <boris.ostrovsky@...cle.com>,
        Christoph Hellwig <hch@....de>,
        Marek Szyprowski <m.szyprowski@...sung.com>
Subject: Re: [Xen-devel] [PATCH] Revert "swiotlb: remove SWIOTLB_MAP_ERROR"

On Tue, Mar 05, 2019 at 09:41:46AM +0000, Julien Grall wrote:
> On Xen, dma_addr_t will always be 64-bit while the phys_addr_t will depend 
> on the MMU type. So we may have phys_addr_t smaller than dma_addr_t from 
> the kernel point of view.

How can dma_addr_t on arm have value > 32-bit when physical
addresses are 32-bit only?