Re: [LAU] performance problems after kernel/microcode update ?

On Fri, 14 Sep 2018 09:59:25 +0200, David Runge wrote: Regarding Meltdown, loosely speaking, if the audio workstation is connected to the Internet, we could boot without disabling PTI. If the audio workstation is used for audio productions, we could boot with disabling PTI and without connecting to the Internet. IIRC the microcode for my CPU not only is required for Spectre mitigation, but also to make TSC available and perhaps to fix other CPU issues, too, so there might be no option to boot without the microcode at all. The '/sys/devices/system/cpu/vulnerabilities/*' "list" is increasing ;). [rocketmouse@archlinux ~]$ uname -a Linux archlinux 4.18.7-rt5-1-rt-securityink #1 SMP PREEMPT RT Thu Sep 13 08:01:15 CEST 2018 x86_64 GNU/Linux [rocketmouse@archlinux ~]$ dmesg | grep micro [ 0.000000] microcode: microcode updated early to revision 0x25, date = 2018-04-02 [ 0.457030] microcode: sig=0x306c3, pf=0x2, revision=0x25 [ 0.457083] microcode: Microcode Update Driver: v2.2. [rocketmouse@archlinux ~]$ ls -l /sys/devices/system/cpu/vulnerabilities/* -r--r--r-- 1 root root 4096 Sep 15 01:12 /sys/devices/system/cpu/vulnerabilities/l1tf -r--r--r-- 1 root root 4096 Sep 15 01:12 /sys/devices/system/cpu/vulnerabilities/meltdown -r--r--r-- 1 root root 4096 Sep 15 01:12 /sys/devices/system/cpu/vulnerabilities/spec_store_bypass -r--r--r-- 1 root root 4096 Sep 15 01:12 /sys/devices/system/cpu/vulnerabilities/spectre_v1 -r--r--r-- 1 root root 4096 Sep 15 01:12 /sys/devices/system/cpu/vulnerabilities/spectre_v2 [rocketmouse@archlinux ~]$ cat /sys/devices/system/cpu/vulnerabilities/* Mitigation: PTE Inversion; VMX: conditional cache flushes, SMT disabled Mitigation: PTI Mitigation: Speculative Store Bypass disabled via prctl and seccomp Mitigation: __user pointer sanitization Mitigation: Full generic retpoline, IBPB, IBRS_FW