Am 04.01.18 um 12:56 schrieb Darren Reed: > On 4/01/2018 11:51 AM, Mark Heily wrote: >> On Jan 2, 2018 19:05, "Warner Losh" <i...@bsdimp.com> wrote: >> >> The register article says the specifics are under embargo still. That would >> make it hard for anybody working with Intel to comment publicly on the flaw >> and any mitigations that may be underway. It would be unwise to assume that >> all the details are out until the embargo lifts. >> >> >> Details of the flaws are now published at: >> >> https://meltdownattack.com > > The web page has both: meltdown and spectre. > Most people are only talking about meltdown which doesn't hit AMD. > spectre impacts *both* Intel and AMD. > > SuSE are making available a microcode patch for AMD 17h processors that > disables branch prediction: > > https://lists.opensuse.org/opensuse-security-announce/2018-01/msg00004.html
Disabling branch prediction will have a very noticeable effect on execution speed in general (while split page tables only affect programs that perform system calls at a high frequency). I have not fully read the Meltdown and Spectre papers, yet, but I do assume, that the attack at the branch prediction tries to counter KASLR, which we do not support at all in FreeBSD. So, I guess, we do not have to bother with disabling of branch prediction in FreeBSD for the time being? Regards, STefan _______________________________________________ freebsd-current@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
