On 02/11/20 19:01, Andy Lutomirski wrote: > What's the point? Surely the kernel should reliably mitigate the > flaw, and the kernel should decide how to do so. There is some slowdown in trapping #DB and #AC unconditionally. Though for these two cases nobody should care so I agree with keeping the code simple and keeping the workaround. Also, why would this trigger after more than a few hundred cycles, something like the length of the longest microcode loop? HZ*10 seems like a very generous estimate already. Paolo >>> I also think you should print a loud warning >> I'm not so sure on this one, e.g. userspace could just spin up a new instance >> if its malicious guest and spam the kernel log. > pr_warn_once()? If this triggers, it's a *bug*, right? Kernel or CPU. >
