On Thu, Aug 22, 2019 at 06:28:39PM -0700, Sean Christopherson wrote: > On Fri, Aug 23, 2019 at 04:25:16AM +0300, Jarkko Sakkinen wrote: > > On Thu, Aug 22, 2019 at 08:00:15PM +0300, Jarkko Sakkinen wrote: > > > On Thu, 2019-08-22 at 07:50 -0700, Sean Christopherson wrote: > > > > On Thu, Aug 22, 2019 at 05:37:18PM +0300, Jarkko Sakkinen wrote: > > > > > On Mon, 2019-08-12 at 18:12 -0700, Sean Christopherson wrote: > > > > > > Invoke EADD with the userspace source address instead of first copying > > > > > > the data to a kernel page to avoid the overhead of alloc_page() and > > > > > > copy_from_user(). > > > > > > > > > > > > Suggested-by: Andy Lutomirski <luto@xxxxxxxxxx> > > > > > > Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx> > > > > > > > > > > NAK because takes away TCS validation and the commit message > > > > > does not give any reasoning for doing that. > > > > > > > > Doh, I have a thorough explanation, but apparently it never made it from > > > > my head to the changelog. I'll send v2 as a standalone patch. > > > > > > Yeah, w/o explanation I won't just take away functionality :-) > > > > I came to realize that also from security perspective it might be > > helpful to EADD, not from a copy of the source, but from the > > actual source. > > > > So yes, I'm for not supporting copy approach at all. I think this > > viewpoint is important to note in addition to the performance > > perspective. > > Side topic, I'm getting ELDU MAC failures on master. Are there any known > regressions, or should I start debugging? Never mind, think I spotted the issue. Hooray for git diff on branches.
