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
| ||
|
Message-ID: <93b3d627-782d-cae0-2175-77a5a8b3fe6e@linux.intel.com> Date: Mon, 29 Apr 2019 13:10:17 +0800 From: Lu Baolu <baolu.lu@...ux.intel.com> To: Christoph Hellwig <hch@....de> Cc: baolu.lu@...ux.intel.com, David Woodhouse <dwmw2@...radead.org>, Joerg Roedel <joro@...tes.org>, ashok.raj@...el.com, jacob.jun.pan@...el.com, alan.cox@...el.com, kevin.tian@...el.com, mika.westerberg@...ux.intel.com, pengfei.xu@...el.com, Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>, Marek Szyprowski <m.szyprowski@...sung.com>, Robin Murphy <robin.murphy@....com>, iommu@...ts.linux-foundation.org, linux-kernel@...r.kernel.org Subject: Re: [PATCH v3 02/10] swiotlb: Factor out slot allocation and free Hi Christoph, On 4/26/19 11:04 PM, Christoph Hellwig wrote: > On Thu, Apr 25, 2019 at 10:07:19AM +0800, Lu Baolu wrote: >> This is not VT-d specific. It's just how generic IOMMU works. >> >> Normally, IOMMU works in paging mode. So if a driver issues DMA with >> IOVA 0xAAAA0123, IOMMU can remap it with a physical address 0xBBBB0123. >> But we should never expect IOMMU to remap 0xAAAA0123 with physical >> address of 0xBBBB0000. That's the reason why I said that IOMMU will not >> work there. > > Well, with the iommu it doesn't happen. With swiotlb it obviosuly > can happen, so drivers are fine with it. Why would that suddenly > become an issue when swiotlb is called from the iommu code? > I would say IOMMU is DMA remapping, not DMA engine. :-) Best regards, Lu Baolu
Powered by blists - more mailing lists