> On Wed, Jan 31, 2018 at 02:56:24PM +0000, Bjoern A. Zeeb wrote: > > On 31 Jan 2018, at 14:36, Konstantin Belousov wrote: > > > > > Author: kib > > > Date: Wed Jan 31 14:36:27 2018 > > > New Revision: 328625 > > > URL: https://svnweb.freebsd.org/changeset/base/328625 > > > > > > Log: > > > IBRS support, AKA Spectre hardware mitigation. > > > > > For existing processors, you need a microcode update which adds IBRS > > > CPU features, and to manually enable it by setting the > > > tunable/sysctl > > > hw.ibrs_disable to 0. Current status can be checked in sysctl > > > hw.ibrs_active. The mitigation might be inactive if the CPU feature > > > > Can you change the tunable/sysctl to hw.ibrs_enable[d] (and toggle the > > default setting along). > This is done consistently with the hw.clflush_disable. > Anyway, the intent is that the knob will be used for disabling, > since defaults are going to be changed in the near future.
I thought we had something some place that said negative assertions should be avoided if possible. > > I find it highly confusing to have two different sysctls ???disable??? > > and ???active??? and a lot > > of people (and cultures) have trouble with the double negative. > > Also the ???enable[d]??? variant seems to be pre-dominant in the kernel. > > > > Also can we spell IBRS in the sysctl description as ???Indirect Branch > > Restricted Speculation (IBRS)???? > Will do in half a hour. -- Rod Grimes [email protected] _______________________________________________ [email protected] mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "[email protected]"
