Secure in-service firmware update

A method, comprising:

• storing firmware-authentication program code, for authenticating firmware of a computer system, in a protected storage segment (PSS) of a volatile memory, during a system boot;
• configuring a privilege logic circuit to lock all accesses to the PSS;
• after completion of the system boot, operating the computer system “in service” with post boot privileges;
• receiving a trigger to switch to a given version of the firmware, while operating “in service”;
• in response to the trigger, obtaining a privilege to access the PSS, and authenticating the given version of the firmware by executing the firmware-authentication program code from the PSS;
• and
• switching to the given version of the firmware upon successfully authenticating the given version, and taking an alternative action upon failing to authenticate the given version.

A method for securely switching firmware versions in a computer system, the method comprising:

• storing, in a protected storage portion of a volatile memory, software program code which authenticates firmware of the computer system, during a system boot;
• configuring a privilege logic circuit to lock all accesses to the PSS;
• after completion of the system boot, operating the computer system “in service” with post boot privileges;
• receiving a trigger to switch to a given version of the firmware, while operating “in service”;
• and
• in response to the trigger:
• (i) obtaining a privilege to access the protected storage portion;
• (ii) authenticating the given version of the firmware by executing the software program code stored in the protected storage portion;
• (iii) if the given version is authenticated successfully, switching to the given version of the firmware;
• and
• (iv) if the given version is not authenticated successfully, taking an alternative action.