All I was able to find out about the %gs register is, that it seems to be a free to use register on >32bit x86 architectures. It seems that a gs_change is executed before any system-call. Can someone point me to a documentation how this register is used for? — I assume its a register used for kernel-/user-mode switches.
The background of my question is, that I try to understand a kernel stack trace and what exactly happened.
The stack trace was produced from the flush process that reached the