Messages in this thread | | | Subject | Re: [PATCH 2/2] iommu/vt-d: Report superpage support in sysfs | From | David Woodhouse <> | Date | Mon, 03 Aug 2015 15:35:14 +0100 |
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On Mon, 2015-08-03 at 16:30 +0200, Joerg Roedel wrote: > On Tue, Jul 14, 2015 at 03:25:04PM -0600, Alex Williamson wrote: > > We already have the VT-d capability register printed raw, but it > > typically involves a trip to the code or the spec to figure out > > whether superpages are supported. Make this easier with "2M_pages" > > and "1G_pages" sysfs entries that clearly report Y/N. > > > > Signed-off-by: Alex Williamson <alex.williamson@redhat.com> > > --- > > drivers/iommu/intel-iommu.c | 22 ++++++++++++++++++++++ > > 1 file changed, 22 insertions(+) > > Can we make this a generic entry for all iommu types and export a > pagesize bitmap instead?
As long as we don't further entrench the current abomination of advertising all page sizes which are a multiple of 4KiB, which we do to work around KVM brain damage.
I think I did manage to fix that once, with a patch that would abuse pg ->freelist when tearing down the mappings from KVM. Which ISTR was the main problem with fixing the API. I'll see if I can recover enough of my addled memory and revive that...
-- David Woodhouse Open Source Technology Centre David.Woodhouse@intel.com Intel Corporation [unhandled content-type:application/x-pkcs7-signature] | |