It depend. Firstly if i understand what happened - i didnt have option to install or not install fix - in the system info i see the patch is installed without asking KB4056892
I did some test and see small (but visible in charts) performance issues on my i7 6700K.
- in cinebench r15 my result is 1% weaker than default i7 6700k and as it was tested in december
- in 3dmark sky diver 1-2% weaker than on my results from december
- in cpuz is 1% less than earlier
in practice - in games i cant compare all but im sure that now cpu is hotter than it was before. In Wolfenstein New Colossus comparing screenshots with data from afterburner and rivaturner (usage, temps, fps etc) - in same place as i played in December i have +/- 2-3 °C more on cpu , in GTA V i didnt play earlier but yesterday i launched it first time i can say its to hot imo to play - in ultra on 1440p cpu is 70+ °C but here i dont have comparision like i said i didnt play gta v before. But i have playgames video captured and screenshots from other titles like Rise of the Tombrider or Middle-earth: Shadow of War and will compare cpu temps and fps today after work
Here Physics Score before and after fix https://www.3dmark.com/compare/sd/4939041/sd/4952992#