Netgate Discussion Forum
    • Categories
    • Recent
    • Tags
    • Popular
    • Users
    • Search
    • Register
    • Login

    Kernel PTI not enabled by default on Atom C3558 in latest 2.4.4RC

    Scheduled Pinned Locked Moved 2.4 Development Snapshots
    19 Posts 7 Posters 3.9k Views
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as topic
    Log in to reply
    This topic has been deleted. Only users with topic management privileges can see it.
    • MikeV7896M
      MikeV7896
      last edited by

      I'm also running a board with a C3558, the "Disable the Kernel PTI" box is not checked, and I don't see vm.pmap.pti: 1 in my /boot/loader.conf file.

      My system was a clean load of 2.4.4 beta, probably early to mid-August.

      I'll admit that I haven't checked or unchecked this box to change the setting, but my understanding from what you're posting Steve is that if it's not checked, there should be that line in the /boot/loader.conf file. And mine isn't that way.

      The S in IOT stands for Security

      1 Reply Last reply Reply Quote 0
      • C
        Chucko @stephenw10
        last edited by

        @stephenw10 OK, I missed that about loader.conf.local.

        This was a clean installation from scratch on a brand-new box. I had installed a copy of FreeBSD 11.2 to check out the hardware, but I wiped the SSD and changed the format from UFS to ZFS when I installed pfSense.

        From the first time I brought up the dashboard, it has read "Kernel PTI: Disabled". Using sysctl at the command line confirmed it.

        1 Reply Last reply Reply Quote 0
        • stephenw10S
          stephenw10 Netgate Administrator
          last edited by

          Hmm, what I expect to see on a clean install is:

          The check box is unchecked.
          The dashboard reports Kernel PTI is enabled.
          The sysctl is set to 1.
          There is no loader line.

          If you check the box that is reversed and the loader line setting it to 0 is added.

          Steve

          1 Reply Last reply Reply Quote 0
          • C
            Chucko
            last edited by

            I'm sorry for the confusion, I had the state of the checkbox backwards in my report. The "Disable KPTI" box was unchecked by default. But KPTI was not enabled. That's the only difference from what you describe.

            The box is a SuperMicro SYS-E9-200A. It uses their A2SDi-4C-HLN4F motherboard.

            1 Reply Last reply Reply Quote 0
            • GrimsonG
              Grimson Banned
              last edited by Grimson

              Make sure you have a BIOS with the required microcode update, AFAIK Kernel PTI will not self-activate without it.

              1 Reply Last reply Reply Quote 0
              • C
                Chucko
                last edited by

                I have the latest BIOS on this system, version 1.1, dated 8/28/2018.

                1 Reply Last reply Reply Quote 0
                • C
                  Chucko @stephenw10
                  last edited by Chucko

                  @stephenw10 /boot/loader.conf.local was NOT preserved when I upgraded to 2.4.4 RELEASE.

                  This is a bug.

                  Fortunately KPTI is enabled by default this time.

                  1 Reply Last reply Reply Quote 0
                  • stephenw10S
                    stephenw10 Netgate Administrator
                    last edited by

                    Please open a bug report and give as much detail as possible. https://redmine.pfsense.org

                    Steve

                    1 Reply Last reply Reply Quote 0
                    • M
                      maoe-tsuru
                      last edited by maoe-tsuru

                      I have the same issue on my Netgate XG-7100 here:

                      • Hardware: XG-7100
                      • CPU: C3558
                      • BIOS: ADI_PLCC-01.00.00.10
                      • 2.4.4-RELEASE

                      The kernel PTI checkbox is unchecked and the dashboard says Kernel PTI is disabled. /boot/loader.conf doesn't contain vm.pmap.pti: 1.

                      1 Reply Last reply Reply Quote 0
                      • stephenw10S
                        stephenw10 Netgate Administrator
                        last edited by

                        Was that after upgrading to 2.4.4 or a clean install?

                        Steve

                        1 Reply Last reply Reply Quote 0
                        • MikeV7896M
                          MikeV7896
                          last edited by

                          I thought that Atom C3xxx support was added with FreeBSD 11.2, so at some point it would have been a clean install of 2.4.4... though it could have been an upgrade from beta to release...

                          BTW, I have the same SuperMicro board as the OP, with the same BIOS update, and I'm still not seeing PTI enabled, even after checking and unchecking the advanced setting box. I haven't tried forcing it myself with loader.conf.local. My system was running 2.4.4 snapshots, and is currently running 2.4.4 release, though it was an upgrade from the RC version.

                          The S in IOT stands for Security

                          C 1 Reply Last reply Reply Quote 0
                          • jimpJ
                            jimp Rebel Alliance Developer Netgate
                            last edited by

                            If PTI defaults to off, congratulations, your CPU is not affected by Meltdown and does not need PTI.

                            Some extra clarification text here: https://redmine.pfsense.org/issues/9026

                            Remember: Upvote with the 👍 button for any user/post you find to be helpful, informative, or deserving of recognition!

                            Need help fast? Netgate Global Support!

                            Do not Chat/PM for help!

                            1 Reply Last reply Reply Quote 1
                            • stephenw10S
                              stephenw10 Netgate Administrator
                              last edited by

                              It was for C3000 in general but we backported the drivers for our XG-7100 into 2.4.3.

                              However looking into this kernel pti can be disabled by default if the CPU indicates it is not required using the IA32_ARCH_CAP_RDCL_NO bit:
                              https://github.com/freebsd/freebsd/blob/master/sys/x86/x86/identcpu.c#L1627

                              So if you have a new enough CPU you may see this.

                              We have put in some changes to indicate that. The checkbox is effectively 'forced disabled' or default. There is no force enabled option currently.

                              Steve

                              1 Reply Last reply Reply Quote 1
                              • C
                                Chucko @MikeV7896
                                last edited by

                                @virgiliomi As of 2.4.4 release, my system is showing KPTI enabled on the dashboard.

                                1 Reply Last reply Reply Quote 0
                                • First post
                                  Last post
                                Copyright 2025 Rubicon Communications LLC (Netgate). All rights reserved.