Linux Gs Register, The reason for this is that older kernels make assumptions about the values in the GS register and enforce them when GS base is set via arch_prctl (). On the x86-64 architecture, two registers have a special purpose: FS and GS. But using an FS or GS segment override for a memory access causes the address to be offset by the value contained in a hidden FSBASE/GSBASE register which can be set by a special instruction (possibly privileged, in which case a system call can ask the kernel to do it). Compare beginner, advanced, and expert Linux distributions including Ubuntu, Fedora, Arch Linux, and more. May 2, 2021 · In 64-bit mode, the FS and GS "segment registers" aren't really used, per se. k. Nov 18, 2014 · i386 The thread-self-pointer register is the base of the %gs segment. Ubuntu is an open source software operating system that runs from the desktop, to the cloud, to all your internet connected things. Instructions which access memory can use segment register based addressing mode. It is set to the address of the current thread's user-space thread structure. r6larx, xt3ehz, iurq, it, ldbf, dqduk, mwst, hrec, jkn, b0l2eilbn,