On 09/10/2018 04:46 AM, Jiri Kosina wrote: > On Mon, 10 Sep 2018, Jiri Kosina wrote: > >>> That looks much more palatable. One missing piece is the sysfs >>> mitigation file for spectre v2. That should reflect STIPB state as well. >> >> FWIW, we're missing a bit more in that area, namely RSB stuffing on >> context switch, IBRS (even through only around fw) and IBPB; those are >> only signalled in dmesg during bootup. > > Nah, IBPB is actuall there, sorry. So I'll add reporting of STIBP + fixup > the missing reporting of RSB_CTXSW for v6. >
I anticipate that STIBP could affect workloads with a lot of indirect branches (see previous discussion with Andrea). We should have a knob for people to opt in or opt out of STIBP. Thanks. Tim
