Tag · x86-64

Follow a thread-local variable from its ELF initialization template to the current thread's memory. Decode four access models, watch the linker replace general code with fixed offsets, and reproduce the static TLS limit encountered by dynamically loaded libraries.

Four stages have only read input. This lab writes output for the first time: plan a minimal executable image, serialize the ELF header and two program headers by hand, and let the Linux kernel run it and return 42.

Follow a runnable Linux program from an unresolved call to four final instruction bytes. Distinguish section offsets, file offsets, P, and next RIP before deriving S+A-P; then explore negative displacements, absolute pointers, addends, overflow, and instruction relaxation.

Follow a call across two source files to discover what the compiler, linker, and loader each know. Inspect a real Linux executable, diagnose failures at four stages, and establish the native environment used throughout the series.