On 4/26/19 12:26 AM, Sebastian Andrzej Siewior wrote: >> That's just a guess, though. >> >> If we care, I think we should just use XSAVE instead of XSAVEOPT and >> trying to reconstruct the init state in software. > We can't use XSAVE directly in the slowpath. We need to reconstruct the > init state. We have the mxcsr quirk. We would need just to extend it and > set the FP area to init state if the FP state is missing like we do in > fpstate_sanitize_xstate(). Can you remind me why we can't use XSAVE directly in the slow path?
