Re: [gentoo-user] Re: Expect a ~15% average slowdown if you use an Intel processor

[Adam Carter]

>
> The settings relevant to Spectre are:
> CONFIG_BPF_JIT - this being set to y is enough to make Intel
> processors vulnerable to variant 1/2.  This being set to y is
> necessary, but not sufficient, for making AMD vulnerable to variant 1.
> net.core.bpf_jit_enable - this being set to 1 along with the config
> option being set is sufficient to make AMD vulnerable to variant 1.
> This setting has no effect on making Intel vulnerable to variant 1 or
> 2.  I suspect this sysctl item won't appear unless it is loaded into
> the kernel in the first place.


Thanks for the clarification. I checked my three systemd systems and all
are;
# CONFIG_BPF_JIT is not set

systemd ebuild is looking for;
$ grep -i bpf /usr/portage/sys-apps/systemd/systemd-2*
/usr/portage/sys-apps/systemd/systemd-235-r1.ebuild:        kernel_is -ge 4
10 && CONFIG_CHECK+=" ~CGROUP_BPF"
/usr/portage/sys-apps/systemd/systemd-236-r4.ebuild:        kernel_is -ge 4
10 && CONFIG_CHECK+=" ~CGROUP_BPF"