I was using this .:
GRUB_CMDLINE_LINUX_DEFAULT="........ nopti noibrs noibpb"
but then I used spectre-meltdown-checker, and saw I had spectre_v2 mitigation path enabled, so I saw It was able to disable it as well.. so Now I disabled it and seems to get some litle speed gain with spectre_v2 disabled.:
GRUB_CMDLINE_LINUX_DEFAULT="........ nospectre_v2 nopti noibrs noibpb"
What else can I disable, and how can I do it?, I saw still some security pathes are in green, among them spectre_v1 and Foreshadow's patches.
sudo spectre-meltdown-checker
Code: Select all
Kernel is Linux 4.4.167-0404167-generic #201812130444 SMP Thu Dec 13 09:47:44 UTC 2018 x86_64
CPU is Genuine Intel(R) CPU 575 @ 2.00GHz
Hardware check
* Hardware support (CPU microcode) for mitigation techniques
* Indirect Branch Restricted Speculation (IBRS)
* SPEC_CTRL MSR is available: NO
* CPU indicates IBRS capability: NO
* Indirect Branch Prediction Barrier (IBPB)
* PRED_CMD MSR is available: NO
* CPU indicates IBPB capability: NO
* Single Thread Indirect Branch Predictors (STIBP)
* SPEC_CTRL MSR is available: NO
* CPU indicates STIBP capability: NO
* Speculative Store Bypass Disable (SSBD)
* CPU indicates SSBD capability: NO
* L1 data cache invalidation
* FLUSH_CMD MSR is available: NO
* CPU indicates L1D flush capability: NO
* Enhanced IBRS (IBRS_ALL)
* CPU indicates ARCH_CAPABILITIES MSR availability: NO
* ARCH_CAPABILITIES MSR advertises IBRS_ALL capability: NO
* CPU explicitly indicates not being vulnerable to Meltdown (RDCL_NO): NO
* CPU explicitly indicates not being vulnerable to Variant 4 (SSB_NO): NO
* CPU/Hypervisor indicates L1D flushing is not necessary on this system: NO
* Hypervisor indicates host CPU might be vulnerable to RSB underflow (RSBA): NO
* CPU supports Software Guard Extensions (SGX): NO
* CPU microcode is known to cause stability problems: NO (model 0xf family 0x6 stepping 0xd ucode 0xa4 cpuid 0x6fd)
* CPU microcode is the latest known available version: YES (latest version is 0xa4 dated 2010/10/02 according to builtin MCExtractor DB v84 - 2018/09/27)
* CPU vulnerability to the speculative execution attack variants
* Vulnerable to CVE-2017-5753 (Spectre Variant 1, bounds check bypass): YES
* Vulnerable to CVE-2017-5715 (Spectre Variant 2, branch target injection): YES
* Vulnerable to CVE-2017-5754 (Variant 3, Meltdown, rogue data cache load): YES
* Vulnerable to CVE-2018-3640 (Variant 3a, rogue system register read): YES
* Vulnerable to CVE-2018-3639 (Variant 4, speculative store bypass): YES
* Vulnerable to CVE-2018-3615 (Foreshadow (SGX), L1 terminal fault): NO
* Vulnerable to CVE-2018-3620 (Foreshadow-NG (OS), L1 terminal fault): YES
* Vulnerable to CVE-2018-3646 (Foreshadow-NG (VMM), L1 terminal fault): YES
CVE-2017-5753 aka 'Spectre Variant 1, bounds check bypass'
* Mitigated according to the /sys interface: YES (Mitigation: __user pointer sanitization)
* Kernel has array_index_mask_nospec: YES (1 occurrence(s) found of x86 64 bits array_index_mask_nospec())
* Kernel has the Red Hat/Ubuntu patch: NO
* Kernel has mask_nospec64 (arm64): NO
> STATUS: NOT VULNERABLE (Mitigation: __user pointer sanitization)
CVE-2017-5715 aka 'Spectre Variant 2, branch target injection'
* Mitigated according to the /sys interface: NO (Vulnerable)
* Mitigation 1
* Kernel is compiled with IBRS support: YES
* IBRS enabled and active: NO
* Kernel is compiled with IBPB support: YES
* IBPB enabled and active: NO
* Mitigation 2
* Kernel has branch predictor hardening (arm): NO
* Kernel compiled with retpoline option: YES
> STATUS: VULNERABLE (IBRS+IBPB or retpoline+IBPB is needed to mitigate the vulnerability)
CVE-2017-5754 aka 'Variant 3, Meltdown, rogue data cache load'
* Mitigated according to the /sys interface: NO (Vulnerable)
* Kernel supports Page Table Isolation (PTI): YES
* PTI enabled and active: UNKNOWN (dmesg truncated, please reboot and relaunch this script)
* Reduced performance impact of PTI: NO (PCID/INVPCID not supported, performance impact of PTI will be significant)
* Running as a Xen PV DomU: NO
> STATUS: VULNERABLE (PTI is needed to mitigate the vulnerability)
CVE-2018-3640 aka 'Variant 3a, rogue system register read'
* CPU microcode mitigates the vulnerability: NO
> STATUS: VULNERABLE (an up-to-date CPU microcode is needed to mitigate this vulnerability)
CVE-2018-3639 aka 'Variant 4, speculative store bypass'
* Mitigated according to the /sys interface: NO (Vulnerable)
* Kernel supports speculation store bypass: YES (found in /proc/self/status)
> STATUS: VULNERABLE (Your CPU doesn't support SSBD)
CVE-2018-3615 aka 'Foreshadow (SGX), L1 terminal fault'
* CPU microcode mitigates the vulnerability: N/A
> STATUS: NOT VULNERABLE (your CPU vendor reported your CPU model as not vulnerable)
CVE-2018-3620 aka 'Foreshadow-NG (OS), L1 terminal fault'
* Mitigated according to the /sys interface: YES (Mitigation: Page Table Inversion)
* Kernel supports PTE inversion: NO
* PTE inversion enabled and active: NO
> STATUS: NOT VULNERABLE (Mitigation: Page Table Inversion)
CVE-2018-3646 aka 'Foreshadow-NG (VMM), L1 terminal fault'
* Information from the /sys interface:
* This system is a host running an hypervisor: NO
* Mitigation 1 (KVM)
* EPT is disabled: N/A (the kvm_intel module is not loaded)
* Mitigation 2
* L1D flush is supported by kernel: YES (found flush_l1d in kernel image)
* L1D flush enabled: UNKNOWN (unrecognized mode)
* Hardware-backed L1D flush supported: NO (flush will be done in software, this is slower)
* Hyper-Threading (SMT) is enabled: NO
> STATUS: NOT VULNERABLE (this system is not running an hypervisor)
> SUMMARY: CVE-2017-5753:OK CVE-2017-5715:KO CVE-2017-5754:KO CVE-2018-3640:KO CVE-2018-3639:KO CVE-2018-3615:OK CVE-2018-3620:OK CVE-2018-3646:OK
