3 ms·
Which OSes are actually imposing DMA restrictions on internal cards? That feels like something that would impose noticeable overhead, but I guess I can imagine
by mjg59 1y ago
Which OSes are actually imposing DMA restrictions on internal cards? That feels like something that would impose noticeable overhead, but I guess I can imagine a special mode that enforces this for competitive gaming...
- kbolino 1y agoIt's not a global on-off switch. With a proper IOMMU, the hypervisor/operating system can lock out specific devices from DMA access, or confine them to specific address ranges.
- strstr 1y agoAllegedly some of the anticheats are configuring the IOMMU through Windows APIs (vanguard, faceit, and a smattering of chinese anticheats). It’s hard to find good public information though. They do some mix of blocking access and deliberately leaving some pages as bait (and monitoring iommu d-bits/faults)
- Deathmax 1y agoRiot documents the need to have IOMMU support enabled for Vanguard: https://support-valorant.riotgames.com/hc/en-us/articles/22291331362067-Vanguard-Restrictions https://support-valorant.riotgames.com/hc/en-us/articles/222...