Unless you move the stack pointer by more than a page (the stack in Linux grows automatically: IIRC any access to at most 64k below the stack pointer is conside

Unless you move the stack pointer by more than a page (the stack in Linux grows automatically: IIRC any access to at most 64k below the stack pointer is considered to be an attempt to grow the stack, because the compiler may very well reorder a change in SP in a function's prelude and an access to the newly-allocated stack frame). Edit: I'm sorry, I was somewhat wrong. Accessing stack below SP is considered a bug, but x86 enter instruction can make it seem like such an access has taken place if it faults: http://lxr.free-electrons.com/source/arch/x86/mm/fault.c?v=3.2#L1136 http://lxr.free-electrons.com/source/arch/x86/mm/fault.c?v=3...