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
| ||
|
Date: Wed, 29 Mar 2017 11:42:18 +0200 From: 'Joerg Roedel' <jroedel@...e.de> To: "Nath, Arindam" <Arindam.Nath@....com> Cc: "Deucher, Alexander" <Alexander.Deucher@....com>, 'Joerg Roedel' <joro@...tes.org>, Bjorn Helgaas <bhelgaas@...gle.com>, "linux-pci@...r.kernel.org" <linux-pci@...r.kernel.org>, "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>, Daniel Drake <drake@...lessm.com> Subject: Re: [PATCH] PCI: Blacklist AMD Stoney GPU devices for ATS Hi Arindam, On Wed, Mar 29, 2017 at 07:15:42AM +0000, Nath, Arindam wrote: > Joerg, as per my limited understanding of ATS, the ATC will respond to > invalidation requests after making sure there are no in-flight DMA > transactions with the address requested by IOMMU to be invalidated. > Now since the IOMMU was sending invalidate command to GPU even though > there was no explicit page unmapping request from the graphics > subsystem, we _might_ end up in a situation where the ATC takes longer > than the invalidation timeout to respond to IOMMU. The maximum wait-time in the loop is 100ms. This should be more than enough for the ATC to complete any in-flight transaction and flush its internal TLB. If that is not enough, there is almost certainly something wrong with the hardware. Joerg
Powered by blists - more mailing lists