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Genode OS Framework
armcpluspluscppframeworkgenodegoahypervisorlinuxmicrokernelnovaobject-capabilitiesoperating-systemosdevriscvsculpt-ossel4virtualizationx86
a0abb093ed
The linker scripts use to fill alignment gaps within the text section with the magic value 0x90909090, which correponds to the opcodes of four nop instructions on x86. This patch removes this value because it apparently solves no problem. If, for some reason (e.g., due to a dangling pointer) a thread executes instructions within alignment paddings, NOP instructions are not any better than any other instruction. The program will eventually execute the instructions after the padding, which is most likely fatal. It would be more reasonable to fill the padding with the opcode of an illegal instruction so that such an error can be immediately detected. That said, I cannot remember a single instance, where the fill value has helped us during debugging. Even if the mechanism served a purpose on x86, it is still better to remove it because it does not equally work on the other architectures where the linker scripts are used. I.e., on ARM, the opcode 0x90909090 is not a NOP instruction. |
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================================= Genode Operating System Framework ================================= This is the source tree of the reference implementation of the Genode OS architecture. For a general overview about the architecture, please refer to the project's official website: :Official project website for the Genode OS Framework: [http://genode.org/documentation/general-overview] The current implementation can be compiled for 8 different kernels: Linux, L4ka::Pistachio, L4/Fiasco, OKL4, NOVA, Fiasco.OC, Codezero, and a custom kernel for running Genode directly on ARM-based hardware. Whereas the Linux version serves us as development vehicle and enables us to rapidly develop the generic parts of the system, the actual target platforms of the framework are microkernels. There is no "perfect" microkernel - and neither should there be one. If a microkernel pretended to be fit for all use cases, it wouldn't be "micro". Hence, all microkernels differ in terms of their respective features, complexity, and supported hardware architectures. Genode allows the use of each of the kernels listed above with a rich set of device drivers, protocol stacks, libraries, and applications in a uniform way. For developers, the framework provides an easy way to target multiple different kernels instead of tying the development to a particular kernel technology. For kernel developers, Genode contributes advanced workloads, stress-testing their kernel, and enabling a variety of application use cases that would not be possible otherwise. For users and system integrators, it enables the choice of the kernel that fits best with the requirements at hand for the particular usage scenario. Directory overview ################## The source tree is composed of the following subdirectories: :'doc': This directory contains general documentation. Please consider the following document for a quick guide to get started with the framework: ! doc/getting_started.txt If you are curious about the ready-to-use components that come with the framework, please review the components overview: ! doc/components.txt :'repos': This directory contains the so-called source-code repositories of Genode. Please refer to the README file in the 'repos' directory to learn more about the roles of the individual repositories. :'tool': Source-code management tools and scripts. Please refer to the README file contained in the directory. Contact ####### The best way to get in touch with Genode developers and users is the project's mailing list. Please feel welcome to join in! :Genode Mailing Lists: [http://genode.org/community/mailing-lists]