Re: Fwd: USB device uses dma on its MMIO region?

On Thu, Jan 22, 2015 at 3:41 PM, Alan Stern wrote: > On Thu, 22 Jan 2015, Elena Ufimtseva wrote: > >> On Thu, Jan 22, 2015 at 1:10 PM, Alan Stern >> wrote: >> > On Thu, 22 Jan 2015, Elena Ufimtseva wrote: >> > >> >> Hello >> >> >

Re: Fwd: USB device uses dma on its MMIO region?

On Thu, Jan 22, 2015 at 1:10 PM, Alan Stern wrote: > On Thu, 22 Jan 2015, Elena Ufimtseva wrote: > >> Hello >> >> While working on IOMMU related problem for Xen Hypervisor, >> it was discovered that on some machines IOMMU page faults are triggered >> on certa

Fwd: USB device uses dma on its MMIO region?

Hello While working on IOMMU related problem for Xen Hypervisor, it was discovered that on some machines IOMMU page faults are triggered on certain addresses and requests that cause this are DMA requests with source device identified as USB Host controllers. Further analysis showed that faulting a