On Mon, May 08, 2023 at 09:44:23PM +0200, Thomas Gleixner wrote: > + /* APIC ID not found in the table. Drop the trampoline lock and bail. */ > + movq trampoline_lock(%rip), %rax Again: movl $0, (%rax) is sufficient for unlock. > + lock > + btrl $0, (%rax)