TL;DR: HOST MITIGATION FEATURES REPORT: https://bugs.launchpad.net/intel/+bug/1828495/comments/15
OLD QEMU GUEST MIT FEATURES REPORT: https://bugs.launchpad.net/intel/+bug/1828495/comments/16 NEW QEMU GUEST MIT FEATURES REPORT: https://bugs.launchpad.net/intel/+bug/1828495/comments/17 MIT FEATURES REPORT DELTA FROM OLD TO NEW: https://bugs.launchpad.net/intel/+bug/1828495/comments/18 Meaning we basically have enabled INSIDE the GUEST: * Hardware support (CPU microcode) for mitigation techniques * Enhanced IBRS (IBRS_ALL) * CPU indicates ARCH_CAPABILITIES MSR availability: YES * ARCH_CAPABILITIES MSR advertises IBRS_ALL capability: YES * CPU explicitly indicates not being vulnerable to Meltdown/L1TF (RDCL_NO): YES * CPU/Hypervisor indicates L1D flushing is not necessary on this system: NO and * CPU vulnerability to the speculative execution attack variants * Vulnerable to CVE-2017-5754 (Variant 3, Meltdown, rogue data cache load): NO * Vulnerable to CVE-2018-3620 (Foreshadow-NG (OS), L1 terminal fault): NO * Vulnerable to CVE-2018-3646 (Foreshadow-NG (VMM), L1 terminal fault): NO -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1828495 Title: [KVM][CLX] CPUID_7_0_EDX_ARCH_CAPABILITIES is not enabled in VM. Status in intel: New Status in linux package in Ubuntu: Confirmed Status in qemu package in Ubuntu: Confirmed Status in linux source package in Bionic: New Status in qemu source package in Bionic: Confirmed Status in linux source package in Cosmic: New Status in qemu source package in Cosmic: Confirmed Status in linux source package in Disco: New Status in qemu source package in Disco: Confirmed Status in linux source package in Eoan: Confirmed Status in qemu source package in Eoan: Confirmed Bug description: [Impact] * QEMU does not support IceLake and CascadeLake CPUs specific features. * Most important feature to be supported is: IA32_ARCH_CAPABILITIES MSR. * With IA32_ARCH_CAPABILITIES, QEMU is able to advertise HW mitigations: - Rogue Data Cache Load - Enhanced IBRS - RSB Alternate - L1D flush need on VMENTRY - speculative Store Bypass to guests, as described in document: Intel 336996-Speculative-Execution-Side-Channel-Mitigations.pdf [Test Case] * From Original Description: """ 1. Boot up guest using: -cpu Cascadelake-Server [root@clx-2s2 yexin]# qemu-system-x86_64 -accel kvm -drive if=virtio,id=hd,file=/home/x/x,format=qcow2 -m 4096 -smp 4 -cpu Cascadelake-Server -serial stdio char device redirected to /dev/pts/3 (label serial0) qemu-system-x86_64: warning: host doesn't support requested feature: CPUID.07H:ECX [bit 4] qemu-system-x86_64: warning: host doesn't support requested feature: CPUID.07H:ECX [bit 4] qemu-system-x86_64: warning: host doesn't support requested feature: CPUID.07H:ECX [bit 4] qemu-system-x86_64: warning: host doesn't support requested feature: CPUID.07H:ECX [bit 4] 2. To check CPU ID related to features[FEAT_7_0_EDX] ：CPUID_7_0_EDX_ARCH_CAPABILITIES Expected Result: Both host and guest's CPUID.07H EDX bit 29 should be 1. Actual Result: Host's cpuid: 0x00000007 0x00: eax=0x00000000 ebx=0xd39ffffb ecx=0x00000818 edx=0xbc000000 (EDX bit 29=1) Guest's cpuid : 0x00000007 0x00: eax=0x00000000 ebx=0xd19f0fb9 ecx=0x00000818 edx=0x84000000 (EDX bit 29=0) Commit:2bdb76c015df7125783d8394d6339d181cb5bc30 Target Kerned: 5.1 Target Release: 19.10 """ [Regression Potential] * Most changes are related to CPU type definitions and its supported features. They are all based in upstream changes but, for obvious reasons, backporting and/or cherry-picking those could bring issues. Biggest concern is breaking something that currently works. Right now, the parts being changed that could affect other CPU types would be related to a small refactoring of how the features are organized, and that would be seen right away when trying to start a new VM after the package is installed. * Other tests, related to the features being backported, are being done by our KVM regression tests, including migration combinations, to reduce chances that a regression is introduced. [Other Info] * N/A To manage notifications about this bug go to: https://bugs.launchpad.net/intel/+bug/1828495/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
