On Fri, Nov 24, 2017 at 06:23:42PM +0100, Ingo Molnar wrote: > From: Andy Lutomirski <[email protected]> > > By itself, this is useless. It gives us the ability to run some final > code before exit that cannnot run on the kernel stack. This could > include a CR3 switch a la KAISER or some kernel stack erasing, for > example. (Or even weird things like *changing* which kernel stack > gets used as an ASLR-strengthening mechanism.) > > The SYSRET32 path is not covered yet. It could be in the future or > we could just ignore it and force the slow path if needed. > > Signed-off-by: Andy Lutomirski <[email protected]> > Signed-off-by: Thomas Gleixner <[email protected]> > Cc: Borislav Petkov <[email protected]> > Cc: Brian Gerst <[email protected]> > Cc: Dave Hansen <[email protected]> > Cc: Josh Poimboeuf <[email protected]> > Cc: Linus Torvalds <[email protected]> > Cc: Peter Zijlstra <[email protected]> > Link: > https://lkml.kernel.org/r/d350017000eed20922c3b2711a2d9229dc809256.1511497875.git.l...@kernel.org > Signed-off-by: Ingo Molnar <[email protected]> > --- > arch/x86/entry/entry_64.S | 55 > +++++++++++++++++++++++++++++++++++++++++++---- > 1 file changed, 51 insertions(+), 4 deletions(-)
Nice commenting, future generations will appreciate it! :-) Reviewed-by: Borislav Petkov <[email protected]> -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.
