There have been other recent vulnerabilities, like the ax/ah thing described in [1] or TLBleed that have relied on SMT, but not Meltdown or the original Spectre

There have been other recent vulnerabilities, like the ax/ah thing described in [1] or TLBleed that have relied on SMT, but not Meltdown or the original Spectre variants. [1] http://gallium.inria.fr/blog/intel-skylake-bug/ http://gallium.inria.fr/blog/intel-skylake-bug/