Thanks Unman. 26.07.2017, 17:21, "Unman" <[email protected]>: > On Tue, Jul 25, 2017 at 05:14:45PM +0300, private user82 wrote: >> I am concerned about the recent bug affecting Skylake and Kaby Lake gen >> Intel processors - >> https://lists.debian.org/debian-devel/2017/06/msg00308.html >> >> As BIOS updates aren't yet available from many mobo manufacturers, how can >> we Qubes users best defend ourselves against an exploit? In this post I am >> hoping to reach out to someone who may be able to comment on how we can best >> configure our platforms until a fix is available. >> >> Following the advice in the linked Debian advisory, I have disabled >> hyper-threading in the BIOS settings. My questions are as follows: >> >> 1) When I check /proc/cpuinfo in dom0, 'ht' remains listed as a flag >> (capability). Running $ lscpu in dom0 indicates that 'Threads per core: 1' >> so I assume the BIOS has in fact disabled hyper-threading. Is this correct, >> or should the flag also disappear when functionality is disabled in BIOS >> settings? >> >> 2) Is it safe to run multiple VCPUs (up to the number of physical cores) >> for each Guest VM. Or, in light of this bug, should we only be using a >> single VCPU for each guest? >> >> Many thanks in advance. > > I seem to recall that Xen used to advise disabling hyperthreading, and > VMWare counsel against its use when provisioning vcpus. > In general there's no advantage in assigning more than physical cores to any > VM. > > On the specifics, I *think* that cpuinfo reports capabilities even if > they have been diabled, so that isnt an issue. > > I dont see any issue in assigning multiple vcpus up to the number of > physical cores. I dont think that bug is relevant to the decision.
-- You received this message because you are subscribed to the Google Groups "qubes-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/qubes-users/315281501502066%40web9o.yandex.ru. For more options, visit https://groups.google.com/d/optout.
