lkml.org 
[lkml]   [2009]   [Oct]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRe: [PATCH 4/5] intel-iommu: Reinstate RMRRs if a device is removed from passthrough domain
    From
    Date
    On Mon, 2009-10-26 at 17:25 -0600, Alex Williamson wrote:
    > When a device is setup for passthrough it has full access to memory
    > so processing the RMRRs is unnecessary. However, if we remove the device
    > from the si_domain, we need to reinstate the associated RMRRs.
    >
    > Signed-off-by: Alex Williamson <alex.williamson@hp.com>

    If your device is doing DMA to host memory autonomously, you may still
    have problems with this patch -- you take it out of the si_domain and
    then there's a period of time before you reapply the RMRRs, during which
    its DMA may be prevented.

    You want to set up the new domain first, then switch the device over to
    it atomically.

    --
    David Woodhouse Open Source Technology Centre
    David.Woodhouse@intel.com Intel Corporation



    \
     
     \ /
      Last update: 2009-10-27 09:19    [W:0.021 / U:60.968 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site