On Thu, May 14, 2020 at 7:31 PM Sreyan Chakravarty <sreyan32@xxxxxxxxx> wrote: > I am in the process of reading this detailed article about the bug: > > https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html > > > Meanwhile, I wanted to know if any one here has the same problem and > what they did for mitigations. Your linked document [1] describes in detail how to mitigate and also lists the associated performance degradation. LWN also provides a good summary for L1TF [2]. On my private machines with older CPUs, I tend to use mitigations=off to disable all CPU mitigation techniques introduced since Meltdown in order to gain some performance back. I/O and context switches in general are really slow with enabled mitigations on Sandy and Ivy Bridge, so I am willing to take some risks on these platforms, which is of course not recommended and possibly a really bad idea :-) $ grep . /sys/devices/system/cpu/vulnerabilities/* /sys/devices/system/cpu/vulnerabilities/itlb_multihit:KVM: Vulnerable /sys/devices/system/cpu/vulnerabilities/l1tf:Mitigation: PTE Inversion; VMX: vulnerable /sys/devices/system/cpu/vulnerabilities/mds:Vulnerable; SMT vulnerable /sys/devices/system/cpu/vulnerabilities/meltdown:Vulnerable /sys/devices/system/cpu/vulnerabilities/spec_store_bypass:Vulnerable /sys/devices/system/cpu/vulnerabilities/spectre_v1:Vulnerable: __user pointer sanitization and usercopy barriers only; no swapgs barriers /sys/devices/system/cpu/vulnerabilities/spectre_v2:Vulnerable, IBPB: disabled, STIBP: disabled /sys/devices/system/cpu/vulnerabilities/tsx_async_abort:Not affected [1] https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html#mitigation-control-on-the-kernel-command-line [2] https://lwn.net/Articles/762570/ _______________________________________________ users mailing list -- users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to users-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@xxxxxxxxxxxxxxxxxxxxxxx
