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Data Memory-dependent Prefetcher
A data memory-dependent prefetcher (DMP) is a cache prefetcher that looks at cache memory content for possible pointer values, and prefetches the data at those locations into cache if it sees memory access patterns that suggest following those pointers would be useful. As of 2022, data prefetching was already a common feature in CPUs, but most prefetchers do not inspect the data within the cache for pointers, instead working by monitoring memory access patterns. Data memory-dependent prefetchers take this one step further. The DMP in Apple's M1 computer architecture was demonstrated to be capable of being used as a memory side-channel in an attack published in early 2024. At that time its authors did not know of any practical way to exploit it. The DMP was subsequently discovered to be even more opportunistic than previously thought, and has now been demonstrated to be able to be used to effectively attack a variety of cryptographic algorithms in work called GoFetch GoFetch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prefetching (computing)
This glossary of computer hardware terms is a list of definitions of terms and concepts related to computer hardware, i.e. the physical and structural components of computers, architectural issues, and peripheral devices. A B C D E F G H I J K L M N O P R S T U V W Z See also *List of computer term etymologies *Glossary of backup terms *Glossary of computer graphics * Glossary of computer science * Glossary of computer software terms * Glossary of e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cache (computing)
In computing, a cache ( ) is a hardware or software component that stores data so that future requests for that data can be served faster; the data stored in a cache might be the result of an earlier computation or a copy of data stored elsewhere. A ''cache hit'' occurs when the requested data can be found in a cache, while a ''cache miss'' occurs when it cannot. Cache hits are served by reading data from the cache, which is faster than recomputing a result or reading from a slower data store; thus, the more requests that can be served from the cache, the faster the system performs. To be cost-effective and to enable efficient use of data, caches must be relatively small. Nevertheless, caches have proven themselves in many areas of computing, because typical computer applications access data with a high degree of locality of reference. Such access patterns exhibit temporal locality, where data is requested that has been recently requested already, and spatial locality, where ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pointer (computer Programming)
In computer science, a pointer is an object in many programming languages that stores a memory address. This can be that of another value located in computer memory, or in some cases, that of memory-mapped computer hardware. A pointer ''references'' a location in memory, and obtaining the value stored at that location is known as ''dereferencing'' the pointer. As an analogy, a page number in a book's index could be considered a pointer to the corresponding page; dereferencing such a pointer would be done by flipping to the page with the given page number and reading the text found on that page. The actual format and content of a pointer variable is dependent on the underlying computer architecture. Using pointers significantly improves performance for repetitive operations, like traversing iterable data structures (e.g. strings, lookup tables, control tables and tree structures). In particular, it is often much cheaper in time and space to copy and dereference pointers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apple M1
Apple M1 is a series of ARM architecture, ARM-based system-on-a-chip, systems-on-a-chip (SoCs) Apple silicon, designed by Apple Inc. as a central processing unit (CPU) and graphics processing unit (GPU) for its Mac (computer), Mac desktop computer, desktops and Laptop, notebooks, and the iPad Pro and iPad Air (5th generation), iPad Air Tablet computer, tablets. The M1 chip initiated Apple's third Mac transition to Apple silicon, change to the instruction set architecture used by Macintosh computers, switching from Intel to Apple silicon 14 years after they were Mac transition to Intel processors, switched from PowerPC to Intel, and 26 years after the transition from the original Motorola 68000 series to PowerPC. At the time of introduction in 2020, Apple said that the M1 had the world's fastest CPU core "in low power silicon" and the world's best CPU performance per watt. Its successor, Apple M2, was announced on June 6, 2022 at WWDC. The M1 was introduced in November 2020, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Side-channel Attack
In computer security, a side-channel attack is any attack based on extra information that can be gathered because of the fundamental way a computer protocol or algorithm is implemented, rather than flaws in the design of the protocol or algorithm itself (e.g. flaws found in a cryptanalysis of a cryptographic algorithm) or minor, but potentially devastating, mistakes or oversights in the implementation. (Cryptanalysis also includes searching for side-channel attacks.) Timing information, power consumption, electromagnetic leaks, and sound are examples of extra information which could be exploited to facilitate side-channel attacks. Some side-channel attacks require technical knowledge of the internal operation of the system, although others such as differential power analysis are effective as black-box attacks. The rise of Web 2.0 applications and software-as-a-service has also significantly raised the possibility of side-channel attacks on the web, even when transmissions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GoFetch
GoFetch is a family of cryptographic attacks on recent Apple silicon CPUs that exploits the CPU's on-chip data memory-dependent prefetcher (DMP) to investigate the contents of memory. CPUs affected include the M1, M2, M3 and A14 series system-on-a-chip processors. The DMP looks at cache memory content for possible pointer values, and prefetches the data at those locations into cache if it sees memory access patterns that suggest following those pointers would be useful. The GoFetch attacks use those speculative cache fetches to undermine a number of different cryptographic algorithms by using memory access timings to exfiltrate data from those algorithms using timing attacks In cryptography, a timing attack is a side-channel attack in which the attacker attempts to compromise a cryptosystem by analyzing the time taken to execute cryptographic algorithms. Every logical operation in a computer takes time to execute, and .... The authors of GoFetch state that they were un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intel Core
Intel Core is a line of streamlined midrange consumer, workstation and enthusiast computer central processing units (CPUs) marketed by Intel Corporation. These processors displaced the existing mid- to high-end Pentium processors at the time of their introduction, moving the Pentium to the entry level. Identical or more capable versions of Core processors are also sold as Xeon processors for the server and workstation markets. The lineup of Core processors includes the Intel Core i3, Intel Core i5, Intel Core i7, and Intel Core i9, along with the X-series of Intel Core CPUs. Outline Although Intel Core is a brand that promises no internal consistency or continuity, the processors within this family have been, for the most part, broadly similar. The first products receiving this designation were the Core Solo and Core Duo Yonah processors for mobile from the Pentium M design tree, fabricated at 65 nm and brought to market in January 2006. These are substantial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Circuits
Digital electronics is a field of electronics involving the study of digital signals and the engineering of devices that use or produce them. This is in contrast to analog electronics and analog signals. Digital electronic circuits are usually made from large assemblies of logic gates, often packaged in integrated circuits. Complex devices may have simple electronic representations of Boolean logic functions. History The binary number system was refined by Gottfried Wilhelm Leibniz (published in 1705) and he also established that by using the binary system, the principles of arithmetic and logic could be joined. Digital logic as we know it was the brain-child of George Boole in the mid 19th century. In an 1886 letter, Charles Sanders Peirce described how logical operations could be carried out by electrical switching circuits.Peirce, C. S., "Letter, Peirce to A. Marquand", dated 1886, '' Writings of Charles S. Peirce'', v. 5, 1993, pp. 541–3. GooglPreview See Burks, Arthu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
