On 2/4/19 1:40 PM, Borislav Petkov wrote: >> Then, for the weirdo deployments where this feature is not enumerated, >> we have the setcpuid= to fake the enumeration in software. >> >> The reason I'm pushing for setcpuid= instead of a one-off is that I >> don't expect this to be the last time Intel does this. I'd rather have >> one setcpuid= than a hundred things like "ac_split_lock_disable". > So my only issue with this is the user having to type this in in order > to get the feature. > > VS > > automatically enabling it during boot in early_init_intel() or so. No > need for any user intervention. It'll be just like a forgotten CPUID bit > and we've done those before.
Actually, there's one part of all this that I forgot. Will split lock detection be enumerated _widely_? IOW, will my laptop in 5 years enumerate support for it? If so, we surely don't want to enable this everyhwhere: it will break old apps. Doesn't that mean that we need both feature detection and another separate bit for folks to opt-in?
