** Tags removed: intel-kernel-18.10 ** Tags added: intel-kernel-19.04 ** Description changed:
Description: [Impact] Future Intel CPU's like Cascade Lake and GLK+ support Enhanced IBRS. Enhanced IBRS is a H/W mitigation technique for Spectre V2 bug. So, it's important for us to make sure that all the OSV's are using this feature. The patch that enables kernel support for this feature has been taken by Thomas and it's in TIP tree. So, please back port it to all the OSV's. Please find the patch here: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?h=x86/pti&id=706d51681d636a0c4a5ef53395ec3b803e45ed4d [Test Case] For processors that don't support Enhanced IBRS, the test is to ensure that /sys/devices/system/cpu/vulnerabilities/spectre_v2 doesn't change state after applying the patches. This will typically be the string when running on Intel processors that don't support Enhanced IBRS: - "Mitigation: Full generic retpoline, IBPB, IBRS_FW" + "Mitigation: Full generic retpoline, IBPB, IBRS_FW" New Intel processors that do support Enhanced IBRS will display "Enhanced IBRS" in place of "Full generic retpoline" [Regression Potential] Pretty low. The patches are fairly simple and they should only affect new processors. The main concern is around the possibility of regressing IBRS support on processors that don't support Enhanced IBRS - Target Kernel:4.18 - Target Release: 18.10 + Target Kernel:TBD + Target Release: 19.04 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1786139 Title: [GLK/CLX] Enhanced IBRS To manage notifications about this bug go to: https://bugs.launchpad.net/intel/+bug/1786139/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
