Messages in this thread | | | Subject | Re: [PATCH] x86/retpoline: Fill return stack buffer on vmexit | From | David Woodhouse <> | Date | Wed, 10 Jan 2018 23:47:42 +0000 |
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On Wed, 2018-01-10 at 22:51 +0000, David Woodhouse wrote: > In accordance with the Intel and AMD documentation, we need to overwrite > all entries in the RSB on exiting a guest, to prevent malicious branch > target predictions from affecting the host kernel. This is needed both > for retpoline and for IBRS. > > Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> > --- > Untested in this form although it's a variant on what we've had already. > I have an army of machines willing to do my bidding but nested virt > is non-trivial and I figure I might as well post it as someone else > can probably test it in less than the time it takes me to work out how.
Now smoke tested with Intel VT-x, but not yet on AMD. Tom, would you be able to do that?
> This implements the most pressing of the RSB stuffing documented > by dhansen (based our discussions) in https://goo.gl/pXbvBE[unhandled content-type:application/x-pkcs7-signature] | |