On Mon, Jun 10, 2019 at 1:44 PM Kees Cook <keescook@xxxxxxxxxxxx> wrote: > > On Mon, Jun 10, 2019 at 01:25:31PM -0700, Andy Lutomirski wrote: > > The use case for full emulation over xonly is very esoteric. Let's > > change the default to the safer xonly mode. > > Perhaps describe the esoteric cases here (and maybe in the Kconfig help > text)? That should a user determine if they actually need it. (What > would the failure under xonly look like for someone needing emulate?) I added it to the Kconfig text. Right now, the failure will just be a segfault. I could add some logic so that it would log "invalid read to vsyscall page -- fix your userspace or boot with vsyscall=emulate". Do you think that's important? --Andy
