Memory protection is critical for secure and predictable computing, especially in real-time systems. While RISC-V offers isolation through PMP and MMU-based mechanisms, the undeterminism introduced by virtual memory makes MMUs unsuitable for time-sensitive applications. To address this, the RISC-V community is ratifying the Supervisor-mode PMP (SPMP) as a lightweight, PMP-like mechanism for S-mode, along with a dual-stage SPMP version to enable virtualization in MMU-less systems. In this work, we present a comprehensive set of proof-of-concept (PoC) artifacts spanning the hardware, emulation, and software layers, demonstrating how the SPMP can enable secure, MMU-less isolation across the RISC-V stack. These contributions aim to support the ongoing ratification process, and will be open-sourced to benefit the broader RISC-V ecosystem.

This work describes the design and implementation of an open-source IOMMU IP compliant with the ratified version of the RISC-V IOMMU specification (v1.0-rc1). So far, we have designed and implemented a basic IP encompassing only the mandatory features (of the spec) and support for virtualization. which has been successfully validated and evaluated on a single-core CVA6-based SoC. Moving forward, we plan to extend the IP with more advanced features, i.e., optional features such as a hardware performance monitor, memory-resident interrupt files support, etc. We will open-source our IP to the RISC-V community.

Resumen: Las aleaciones para el relleno superficial Fe-Mn-C (Hadfield) han demostrado una excelente resistencia al desgaste bajo altas cargas dinámicas. En los últimos años se han realizado numerosos estudios para aumentar la resistencia al desgaste y mejorar su desempeño, a través de la introducción de otros elementos de aleación. En el presente trabajo se investiga la microestructura y dureza de los depósitos de relleno con alto contenido de Mn y adiciones de 1.2% de V y 2.4% de Si. Los depósitos estudiados se realizaron utilizando electrodos tubulares revestidos fabricados a escala de laboratorio. Las fases y microconstituyentes en el metal depositado se identificaron mediante microscopía óptica (MO), electrónica de barrido (MEB), difracción de rayos X (DRX), dureza y microdureza. De acuerdo a los resultados obtenidos, la adición de V al sistema aleante originó que la fase predominante fuera la austenita. Además, contribuyó a la formación de carburos de vanadio (VC) en la microestructura de la capa de relleno, sin observarse la presencia de carburos complejos. Por otra parte, la presencia de Si favoreció la formación de una red de ferrita interdendrítica. La adición de estos elementos de aleación mejoró las propiedades de estos depósitos, potencializando su uso en aplicaciones que requieren alta resistencia al desgaste bajo altas cargas.

This work presents the first open-source design and implementation of the RISC-V SPMP for hypervisor. We integrated the dual-stage SPMP implementation into an MMU-less 64-bit CVA6 core with the Hypervisor extension enabled. The modified core was functionally validated using a software stack built around the Bao hypervisor. Preliminary results regarding FPGA resource utilization are also provided. Future work includes benchmarking the SPMP-based platform and comparing its performance with conventional MMU-based virtualization. Additionally, we plan to contribute to the RISC-V community by developing a QEMU implementation of the dual-stage SPMP.

Internet of Things (IoT) devices, typically based on low-cost microcontrollers (MCUs), are being deployed on a massive scale while becoming increasingly complex. Virtualization is the de facto solution to secure these systems, but it has not been available on MCUs until now. This paper proposes a virtualization-based Trusted Execution Environment (TEE) architecture leveraging the RISC-V Hypervisor and SPMP extensions. We have implemented a working prototype running the open-source Bao Hypervisor on top of Beyond’s BA51 CPU.

El presente ensayo intenta explicar el sistema político mexicano “comprendiendo” su Constitución. Es un cinismo realista, frente a uno de los sistemas autoritarios sostenidos y de más larga vida que ha podido confundir a politólogos, sociólogos, economistas e historiadores, manteniéndose como la “dictadura perfecta”, diría Mario Vargas Llosa en 1990. La idea es, a propósito de los indicadores que sobre calidad democrática propusieran Diamond y Morlino, se busca experimentar la “democracia mexicana” sometiéndola y “adaptándola” a un análisis crítico. Al final, se puede constatar el “autoritarismo mexicano”, disfrazado en un constitucionalismo presidencial o “metaconstitucionalismo” (Carpizo, 1978), que descansa incluso desde la conformación misma de la Constitución.

This work proposes the inclusion of an element that is considered essential in public policies: evaluation during the implementation process, while warning about other problems that accompany them and that have not been properly resolved, such as the correct identification and delimitation of the problem; its birth and gestation; the times for its development; the lack of citizen participation, especially in its construction and implementation, and the evaluation itself. Taking as reference several definitions and processes, a new model and a new process are suggested, where democratic citizen participation is essential. This does not happen regularly, and public policies are debated between government actions that seek only to preserve power and not to develop the State, which should be its main purpose. In the end, it’s possible to see that multiconceptual definitions and the myriad of processes proposed, while helping to enrich their definition, have made confusion and inefficiency possible.

Purpose To determine the influence of arm-crank exercise in reproductive hormone levels in adults with chronic SCI. Further objectives were to assess the influence of arm-crank exercise on muscle strength and body composition. Materials and Methods Seventeen male adults with complete SCI at or below the 5th thoracic level (T5) volunteered for this study. Participants were randomly allocated to the intervention (n = 9) or control group (n = 8) using a concealed method. The participants in the intervention group performed a 12-week arm-crank exercise program, 3 sessions/week, consisting of warming-up (10-15 min) followed by a main part in arm-crank (20-30 min [increasing 2 min and 30 seconds each three weeks]) at a moderate work intensity of 50-65% of heart rate reserve (HRR) (starting at 50% and increasing 5% each three weeks) and by a cooling-down period (5-10 min). Serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone and estradiol were determined by ELISA. Muscle strength (handgrip) and body composition (waist circumference [WC]) were assessed. Results After the completion of the training program, testosterone level was significantly increased (p = 0.0166;d = 1.14). Furthermore, maximal handgrip and WC were significantly improved. Lastly, a significant inverse correlation was found between WC and testosterone (r =- 0.35; p = 0.0377). Conclusion The arm-crank exercise improved reproductive hormone profile by increasing testosterone levels in adults with chronic SCI. A secondary finding was that it also significantly improved muscle strength and body composition in this group.

Intelligent Tutoring Systems are computer programs that aim at providing personalized instruction to students. In recent years, artificial intelligence conversational robots, usually known as chatterbots, have become very popular in the Internet. In this paper we show how chatterbots can be integrated in e-Learning Systems. To perform such an integration the Service Oriented Architecture paradigm is adopted and e-learning standardization initiatives are considered. A middleware is provided to enable the integration and reuse of chatterbots by e-Learning systems enabling a tight control of their operation. Such middleware takes to account several issues such as authorising users, creating instances, transferring data to and from the chatterbot, assigning permissions to users, and subscribing to events. Our approach is applied to the specific case of TQ-Bot, which is use to track and supervise the student progress and to provide answers orienting the student to the more appropriate course contents.