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| | NX bit - Wikipedia, the free encyclopedia |
 | | Outside of the x86 sphere, a version of NX also exists for Intel's IA-64 which is implemented into the Windows that operates that architecture. | | | The PaX NX technology can emulate an NX bit or NX functionality, or use a hardware NX bit. | | | W^X supports the NX bit on Alpha, AMD64, HPPA, and Sparc processors (but notably, not the Intel EM64T processor, which does not have the NX feature). |
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http://en.wikipedia.org/wiki/NX_bit
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| | Executable - encyclopedia article about Executable. |
| | By definition, computer science is the accumulated knowledge through scientific methodology by computation or by the use of the computer. | | | bits bit (sometimes abbreviated b, see below) is the most basic information unit used in computing and information theory. | | | Or, rather, text files are a special case of binary files, since any file is fundamentally a sequence of bits, and many computer components (for example, all hard disk circuitry and most system software) make no distinction between file types. |
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http://encyclopedia.thefreedictionary.com/Executable
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| | Security Ahoy! Flying the NX Flag on Windows and AMD64 To Stop Attacks |
| | When a page is loaded into memory, the operating system sets the NX bit for that entry in the table to indicate whether the information on that page is data only, and may not be executed. | | | NX, which stands for "No Execute Bit," is a one-bit flag that goes with each entry in the memory address table. | | | The first version of Windows to support run-time checking of the NX bit was Windows XP Service Pack 2. |
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http://www.devx.com/amd/Article/27809/2907?pf=true
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| | NX - Wikipedia, the free encyclopedia |
| | NX bit for marking parts of computer memory as "no execute." | | | Short for NXSecure - a very popular web forum specialising in inane chatter, technical / software support and everything in between. | | | In economics, NX is usually used to represent net exports. |
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http://en.wikipedia.org/wiki/NX
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| | N Encyclopedia Index |
| | Nx from NX bit to NX class starship |
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http://brainyencyclopedia.com/alpha/n.html
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| | CPU-Based Security: The NX Bit |
| | Intel is expected to add NX (or XD) to the next generation of its 90-nanometer-process Pentium 4 "Prescott" CPUs -- bundling the security enhancement with a larger 2MB Level 2 cache and perhaps a faster 1066MHz front-side bus -- in the fourth quarter of this year. | | | For example, with NX in place, the MSBlaster worm would still have caused a denial-of-service (DoS) attack, but would have lost the ability to replicate and spread to other systems. | | | Unlike today's Windows, Win XP SP2 is alert for the status of the NX bit and will whistle a foul -- or raise a "status access violation" exception -- when code attempts to execute from a data page, terminating the process. |
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http://hardware.earthweb.com/chips/article.php/3358421
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| | [No title] |
| | "NX (No-Execute) bit: Initial implementation will not support the NX bit." -- http://www.ussg.iu.edu/hypermail/linux/kernel/0402.3/0276.html "Even though there are some differences between Intel’s and AMD’s 64-bit extended processors’ capabilities, such as NX (non execute) bit featured in AMD64" -- http://www.xbitlabs.com/news/cpu/display/20040325151223.html "Both Intel and Advanced Micro Devices (AMD) have defined and shipped Windows-compatible architectures for execution protection. | | | Until shown that this technology works, say on any number of other working 64 bit OS's, it simply could be a botched design that's waiting for a redesign to get it working. | | | It's currently not enabled, and there's no guarantee that it will be possible to enable it with software / a new BIOS later. |
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http://users.utu.fi/juhehe/jutut/NX-bit.txt
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| | NX fever seizes Intel, Transmeta, VIA, guy in local pub |
| | First implemented in common consumer hardware by AMD (but of course it's been around for ages), the NX bit is designed to help the CPU decide whether or not to execute code. | | | Offloading a bit of this task (no pun intended) to hardware makes good sense, but then again, my programming days mostly ended with VMS. | | | Support at the hardware level should keep the most common types of attacks in check, while also urging programmers to write code that will ultimately perform better. |
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http://arstechnica.com/news/posts/1084986792.html
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| | Transmeta targets Pentium M users with NX security bit InfoWorld News 2004-05-17 By Tom Krazit, IDG News Service |
| | The spokeswoman declined to comment on whether NX functionality would appear before Yonah, the code name for Intel's first dual-core mobile processor expected in 2005, according to sources. | | | Transmeta's processor architecture uses software to control many of the same tasks that are done with hardware components in other chips. | | | Intel can either design a new version of that core or add the NX functionality to future Dothan processors in a new stepping, she said. |
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http://www.infoworld.com/article/04/05/17/HNtransmeta_1.html
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| | Articles - AMD64 |
| | No-Execute bit: While not technically required for 64-bit computing, the âNXâ bit is a processor feature that provides for a more tightly-controlled software environment. | | | Microsoft, however, has explicitly left out 16 bit program support in Windows XP Professional x64 Edition due to problems in getting 16 bit x86 code to run via their WoW64 Subsystem. | | | This is unlike Intel's IA-64, where differences in the underlying ISA means that running 32 bit code is like using an entirely different processor. |
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http://lastring.com/articles/AMD64?mySession=c5346e6cbccdb52741745e668443a212
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| | Linux: x86 No Execute Support |
| | This NX thing is a newcomer, and it is long overdue at that. | | | a heap array, switch on the execute bit for the relevant page, and branch to the array (which would typically contain a return instruction). | | | This property is often abused by exploits when they manage to inject hostile code into this memory, for example via a buffer overflow. |
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http://kerneltrap.org/node/view/3240
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| | AMD64 Linux kernel and the NX bit LG #107 |
| | On clearing the executable stack bit, the program was found to segfault on the Athlon64 system running the x86_64 Linux kernel. | | | The trouble is that the actual address stored in `p' can be determined only at run time depending on what value the user assigns to `m' from the standard input. | | | An ELF binary (or shared library) can be `marked' as requiring (or not requiring) an executable stack. |
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http://linuxgazette.net/107/pramode.html
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| | LWN: x86 NX support |
| | To that end, Ingo Molnar has posted a patch bringing NX support to the x86 architecture; his patch is based on previous work done by Intel and the x86_64 NX support by Andi Kleen. | | | AMD added a no-execute (NX) permission bit to the page table entries in its 64-bit processors; Intel has recently said it will be supporting this mode as well. | | | (NOTE: 64-bit x86_64 kernels already make use of the 64-bit variant of the NX feature - this patch is only meant for 32-bit x86 kernels and distributions.) |
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http://lwn.net/Articles/87814/?format=printable
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| | OSNews.com |
| | So whether AMD implemented it first and Intel followed suit is completely irrelevant, since the software to take advantage of it is simply not in place on the platform that needs it the most. | | | is it not likley that windows would have supported the nx bit much earlier if the chips implemented it earlier? | | | ahh windows dosent support the nx bit until now and why should |
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http://www.osnews.com/comment.php?news_id=7911
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| | t-break - Windows, Linux and the NX bit |
| | to implement NX bit you need to almost recode your software. | | | In NX environment, you cannot execute anything like you did before. | | | Some x86 software still do that thing, and that's what make them doesn't work in SP2 with NX bit enabled. |
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http://www.tbreak.com/forums/printthread.php?t=24360&pp=40
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| | The PC Guide Discussion Forums - EM64T For 64bit CPU |
| | AMD's current implementation of the NX bit isn't enabled on all the K8-based CPU's, and Intel tried to copy AMD's plans for NX just by looking at their whitepapers and got it wrong, so NX capabilities will have to wait until those two get things straightened out. | | | Longhorn has now been scaled down by MS in many critical ways, but NX will still play a large part in the future (despite the fact that MS and Intel and AMD shouldn't be responsible for malicious code! | | | Intel users will have to be satisfied with a lesser "software" implementation of DEP. |
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http://www.pcguide.com/vb/showthread.php?t=33856
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| | [No title] |
| | dims[0] = nval; return 1; } /*------------------------------------------------------------------------- */ int huff_table_gen(freqin, nf, bits, huffval, nval) unsigned char bits[], huffval[]; int freqin[], *nval, nf; /* nf ( | | | > jq); } /*printf("16 bit candidate in slow decode = %#x\n", temp);*/ k = 7; nb = 8; /* here nb is code size - 1 */ while ((ks =(temp >> k)) > dc_maxcode[nb]) { k--; nb++; if (k | | | > jq); } /*printf("16 bit candidate in slow decode = %#x\n", temp);*/ k = 7; nb = 8; /* here nb is code size - 1 */ while ((ks =(temp >> k)) > ac_maxcode[nb]) { k--; nb++; if (k |
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http://sohowww.nascom.nasa.gov/solarsoft/packages/ana/sources/trace_jpeg.c
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| | Aug 05 - UGS NX to Support HP 64-Bit Workstations |
| | UGS’ support for Windows XP Professional x64 Edition will be available with the next release of NX scheduled to begin shipping in the fourth quarter of this year. | | | “Today’s announcement will enable our NX customers to realize improvements in a variety of processor-intensive tasks such as large assembly manipulation, complex product design, advanced engineering analysis and simulation and multi-axis tool path generation. | | | Sep 12 - UGS NX Shows 50% Better Performance with Multi-Core Computers |
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http://www.tenlinks.com/NEWS/PR/ugs/080505_workstation.htm
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| | MS to intro hardware-linked security for AMD64, Itanium, future CPUs The Register |
| | One might speculate that Windows XP support for AMD64 might not be entirely unconnected with NX support. | | | Microsoft is to introduce hardware-linked security technology with Windows XP Service Pack 2, and beyond that will make "additions to Windows" supporting the technology, execution protection (NX). | | | The feature is already supported by shipping AMD K8 and Intel Itanium processor families, and according to Microsoft: "It is expected that future 32 and 64-bit processors will provide execution protection. |
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http://www.theregister.co.uk/2003/11/03/ms_to_intro_hardwarelinked_security
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| | Neowin.net - Windows XP Service Pack 2 to Activate NX bit on AMD chips |
| | The core of AMD’s Enhanced Virus Protection is the so-called NX bit in the page-translation tables that specifies whether instructions can be executed from the page. | | | The capability is also available on Intel’s Itanium and Itanium 2 microprocessors, but is not present in IA32e chips, such as Intel Pentium 4 E also known as Prescott, unlike suggested by certain sources last year. | | | Windows XP Service Pack 2 to Activate NX bit on AMD chips |
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http://www.neowin.net/comments.php?category=main&id=17854
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| | NX-bit, Cool'n'Quiet-like Technologies from Intel Planned - ap0calypse - The Last Stop in Tech |
| | However, pure speed does not seem to be the only advantage of the forthcoming Pentium 4 “Prescott” processor, as the newcomer will feature XD — also known as NX bit — a certain flag that determines whether instructions can be executed from the page. | | | AMD’s 64-bit chips that are in ramping up today also implement Cool’n’Quiet technology that is aimed to make computers more silent. | | | Additionally, the new chips will feature a special technology called AAC that adjusts performance depending on load in order to maintain low heat dissipation and quiet operation of personal computers. |
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http://www.ap0calypse.com/showthread.php?t=549
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| | Sriram Krishnan (Moved to http://blogs.msdn.com/sriram) : NX bit and executable code |
| | I've been following with great interest the NX flag (available in Windows from SP2) onwards which stops people from executing 'data' memory. | | | But what I wonder is- how does this affect languages like Lisp where the 'code is the data'? | | | Sriram Krishnan (Moved to http://blogs.msdn.com/sriram) : NX bit and executable code |
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http://www.dotnetjunkies.com/WebLog/sriram/archive/2004/12/29/39680.aspx
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| | Execute Disable Bit Functionality |
| | In a typical attack, a malicious worm creates a flood of code that overwhelms the processor, allowing the worm to propagate itself to the network, and other computers. | | | Replacing older computers with Execute Disable Bit-enabled systems can halt worm attacks, reducing the need for virus related repairs. | | | Execute Disable Bit allows the processor to classify areas in memory by where application code can execute and where it cannot. |
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http://www.intel.com/business/bss/infrastructure/security/xdbit.htm
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| | Overclockers Forums - Who has NX-bit enabled on their "J"? |
| | AFAIK all J stepping intel prescotts have the NX bit enabled. | | | But from what i read its not something you can enable/disable...only that it enables you to change the multiplier (14x - 17x) and some futural apps should be able to make use of it. | | | The Execute Disable Bit (EDB) has nothing to do with the 14 multiplier. |
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http://www.ocforums.com/showthread.php?t=359265
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| | Windows XP SP-2 |
| | For programs that exhibit issues on 64-bit-based computers that support the No Execute (NX) technology, the new Data Execution Prevention feature that is included with Windows XP SP2 may be preventing the programs from running correctly. | | | For additional information about how to use the Data Execution Prevention feature, click the following article number to view the article in the Microsoft Knowledge Base: |
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http://www.pro1040.com/computer_consulting/windows_xp_sp2.htm
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| | Comments for: Pentium M gets 533MHz front-side bus, NX bit - ja.zz |
| | The only 64-bit part about x86-64 is the memory addressing. | | | x86-64 is just a refined version of ye old x86 with some add registers (NX bit) and 64-bit memory addressing. | | | The chips ride a 533MHz front-side bus that will debut in Intel's upcoming "Alviso" 915GM chipset, which will also bring PCI Express, DDR2, and High Definition Audio to the Pentium M. Babel Fish's translation is a little shaky, but it also looks like the new chips will support the NX bit. |
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http://techreport.com/ja.zz?comments=7834
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| | Neowin.net - Intel confirms NX Bit Prescott stepping |
| | Neowin.net - Intel confirms NX Bit Prescott stepping | | | The features included in the Prescott E0 stepping are the NX Bit (no execute memory protection), an enhanced halt state (C1E), and thermal monitoring 2 (TM2). | | | Intel has told its customers that PAE 36 is needed to support the NX bit for IA-32, and validati The enhanced halt state kicks off when an operating system goes into idle mode, and will lower power consumption. |
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http://www.neowin.net/comments.php?category=main&id=21998
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| | Intel rushes to implement NX bit in September |
| | But it will only be implemented on Pentium 4 560s, 550s, 540s, 530s and 520s at first, and only on LGA 775 versions of the Celeron D at 340, 335, 330 and 325. | | | Intel rushes to implement NX bit in September | | | We've published those details earlier and they're unchanged, and so are Celeron D price cuts slated for that date. |
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http://www.theinquirer.net/?article=17797
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| | AMD Processor Support Forum -> AMD Sempron + 64 OS |
| | Socket A semprons don't support the NX bit, socket 754 and ANY other Athlon64 based Sempron does support it. | | | What's more, the NX function will be disabled too. | | | Right now Semprons supports the NX Bit, where you hear that it will be disabled? |
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http://forums.amd.com/index.php?showtopic=36652
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| | bit-tech.net Fear and loathing in Redmond |
| | Microsoft has tried to stomp on the P2P networks, threatening to take down at least two websites offering the Torrent, including that of Downhill Battle who claimed to be trying to do Microsoft a favour. | | | Most of the problems are due to the new firewall in SP2 being on by default, and the fact that this service pack enables the ‘NX bit’ in AMD64 processors. | | | Despite the slow release of the service pack to the public, it has been zinging round Bit Torrent for some time. |
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http://www.bit-tech.net/column/23
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| | A bit about the NX bit |
| | In fact it seems that NX provides several layers of false security, particularly since it only stops some buffer overflows and whether or not it stops any viruses has yet to be seen yet." | | | "NX protection seems great; it stops viruses dead in their tracks and eliminates those pesky buffer overflows we have been hearing so much about for the last 15 years. |
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http://rootprompt.org/article.php3?article=8131
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| | World History :: Encyclopedia Index -- Nx |
| | INDEX OF ARTICLES: Nx Articles are indexed by the first word of the title, including "A," "The," etc. | | | World History :: Encyclopedia Index -- Nx Events Encyclopedia Localities Companies Surnames Shop |
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http://www.worldhistory.com/wiki/Nx.htm
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