On Tue, Apr 16, 2019 at 9:27 AM Conrad Meyer <c...@freebsd.org> wrote:
> On Tue, Apr 16, 2019 at 7:24 AM Justin Hibbits <chmeeed...@gmail.com> > wrote: > > > > Hi Conrad, > > ... > > [Power] does use bsdinstall to install. How is entropy loaded at > startup, > > which causes the problem noted in github? > > There are a couple very early load sources. loader(8) will load > early-boot entropy from /boot/entropy and pass it to the kernel as a > fake module (entropy_cache_load in loader.conf(5)), similar to > cpu_microcode early load. > > The fallback option is random(4) itself groping into the filesystem > during early auto-conf (SI_SUB_RANDOM:SI_ORDER_FOURTH, IIRC) to access > /boot/entropy directly. > SI_SUB_RANDOM is too early. It's at 0x2160000, while SI_SUB_ROOT_CONF doesn't happen until 0xb000000. > > If it's loaded before > > filesystems get mounted, that could be a problem for us, because /boot > > is on a different filesystem (msdosfs, to be read by petitboot). > > Petitboot also does not have a way to preload modules, so all we have > > at startup, until spawning init, is the kernel. > > Yes, that seems potentially problematic. Can the Power kernel access > the non-msdosfs root filesystem? Let's follow-up offline about > PPC-specific early entropy seeding. I would much prefer we figure out > a way to provide early entropy to Power than disabling or crippling > every early random consumer on the arch. Do you know what the Linux > folks do? > > On Power with darn, we could probably just spin in SI_ORDER_FOURTH > until we have enough darn output to seed random. Similar for x86 CI > images, I guess; though they do not have the loader problem, some > people have non-bsdinstall installation methods. > They do have the loader problem because many means to generate an image don't generate /boot/entropy. Warner _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
