How to fix a corrupted SMC by Catalina 10.15.7SU2 update
•I applied the Catalina 10.15.7 Supplemental Update 2 on my MacBook Pro 2017. Fans went full speed during the install and stayed like this after a first reboot, the Macbook went in a reboot loop, and ultimately did not power at all. It turns out that the SMC was corrupted/erased, leaving the board in SMC bypass state (...)