Hi, On 09/26/2014 08:37 PM, Hans de Goede wrote: > Hi All, > > Just spend some time debugging this and thought I should share this, see: > > https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=762195 > > for details, I've filed a bug to track fixing this in Fedora: > > https://bugzilla.redhat.com/show_bug.cgi?id=1147062 > > There are 2 ways this problem shows itself: > > 1) If using an initrd which has been generated with the troublesome microcode > update into it, things may already crash during the initrd, e.g. in my case > some luks volumes would not unlock because of this > > 2) When booting an older kernel (and thus an older initrd) things start crashing > (mostly systemd* processes, grinding everything to a halt) as soon as udev > from the rootfs loads the microcode update > > 2. often will still get you to an emergency shell, at which point one can > create a /etc/modprobe.conf.d/no_microcode.conf file with: > > blacklist microcode > > In there to work around the problem, then regenerate the initrds for newer > kernels, and you should be good to go until bug 1147062 gets fixed properly. So it seems people were already aware of this and an update is already available: On 09/26/2014 08:34 PM, Carlos O'Donell wrote:> Developers. > > Testers wanted immediately for: > > https://admin.fedoraproject.org/updates/glibc-2.18-16.fc20 > > and > > https://admin.fedoraproject.org/updates/glibc-2.20-4.fc21 > > For Fedora 21 and Fedora 20 we will be disabling Intel TSX > support in POSIX threads effective immediately. This disabling > of TSX support in POSIX threads is in order to prevent users > from crashing their systems when they upgrade microcode_ctl. > > The upgrade to the new microcode_ctl applies the microcode > update for the Intel errata HSW136 and makes all TSX instructions > invalid opcodes. This means that any process on your system > already using POSIX threads, and already using TSX, will fault > with invalid opcode errors when it tries to execute TSX > instructions. > > The best solution is for the microcode update to be done before > userspace starts as part of a single-threaded init process or > something similar. > > Until we support updating microcode in early bootup we won't > enable TSX in POSIX threads. The glibc maintainers have decided > not add code to detect which devices the errata applies to, nor > will code be added to re-read the cpuid values at every TSX usage. > We are going with the simples approach which is to disable TSX > for POSIX threads. > > Cheers, > Carlos. Regards, Hans -- devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/devel Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct
