On Thu, 4 Jan 2018 22:13:16 +0000 Ken Moffat <[email protected]> wrote:
> On Thu, Jan 04, 2018 at 08:16:18PM +0000, Ken Moffat wrote: > > People who follow the news will be aware that big changes have been > > rushed into the linux kernel (and changes are/have been also rolled > > out by microsoft, and apparently by apple). > > > > There are two vulnerabilities, with the shiny names of Meltdown and > > Spectre. Both refer to ways of userspace finding where the kernel > > has been mapped, to try to do harm. Page Table Isolation addresses > > the first of these. Google claim it affects some AMD processors, > > AMD deny this. > > > >.... > > PTI has been pushed into 4.15-rc6 as a matter of urgency, and > > added to 4.14.11 with backports to 4.9 and 4.4 in progress. > > > > Most testing, particularly by the 0-day kernel bot, has been on > > Intel hardware and running this on AMD has uncovered some problems > > which have been addressed in linus's tree and which will be in > > 4.14.12. With 4.14.12, if PTI is selected it will not be used at > > runtime on an AMD machine with the default auto option, although I > > think it can be forced by specifying the 'pti' boot argument. > > > > If a kernel has been built with PTI, it can be disabled by > > specifying 'nopti' in the command line. Once a kernel has booted, > > PTI cannot be enabled or disabled until you reboot. > > > > If you are running with PTI enabled, dmesg will show > > Kernel/User page tables isolation: enabled > > > > > ĸen > -- I have just built a 4.14.11 kernel with PTI and I can't boot it. I get a string of acpi errors and then a panic. As far as I can see, it's the same problem as https://bugzilla.redhat.com/show_bug.cgi?id=1520265. That was cured by a bios update but I wouldn't date to do a thing like that. Looks like I am stuck with 4.12.8 for the time being. The processor is pretty old, an Intel Core2 Duo. Maybe it's too old to be affected by Meltdown. I would value any advice. -- Hazel -- http://lists.linuxfromscratch.org/listinfo/lfs-support FAQ: http://www.linuxfromscratch.org/blfs/faq.html Unsubscribe: See the above information page Do not top post on this list. A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail? http://en.wikipedia.org/wiki/Posting_style
