The CHERI capability model: Revisiting RISC in an age of risk (Light Blue Touchpaper)

Posted Jul 6, 2014 12:35 UTC (Sun) by khim (subscriber, #9252)
In reply to: The CHERI capability model: Revisiting RISC in an age of risk (Light Blue Touchpaper) by PaXTeam
Parent article: The CHERI capability model: Revisiting RISC in an age of risk (Light Blue Touchpaper)

Even according to intel, just read the titles of their own manuals: http://www.intel.com/content/www/us/en/processors/archite....

So now we treat marketing BS as a gospel of truth? Come on. That's just stupid.

Do you have any clue about amd64?

Do you? I know that people who actually work with said architecture treat it as a single one (with significant tweaks here and there, sure). Both GCC and Linux kernel developers put files for x86 and x86-64 into a single subdirectory of their arch directory for a reason. Note that Linux developers initially treated it as two different architectures, but it made no sense and they were eventually merged. Yes, it's quite significant extension, but so is Sparc64 or 32bit and 64bit versions of POWER architecture.

The CHERI capability model: Revisiting RISC in an age of risk (Light Blue Touchpaper)

Posted Jul 6, 2014 15:20 UTC (Sun) by PaXTeam (guest, #24616) [Link]

it's called 'developer manual', not 'marketing BS' but then it's not the first time you've had reading comprehension problems, is it ;).

the directory structure of a source code tree has no bearing on what is a separate architecture (e.g., the BSDs have kept i386/amd64 separate). if anything, it reflects on some wise engineerig design decisions of AMD that kept the two archs close enough that some linux devs managed to drive through the x86 'unification'. as for how successful the x86 merge is:

$ find linux-3.15.3/arch/x86/ | wc -l
1255
$ grep -rwn CONFIG_X86_32 linux-3.15.3/arch/x86/ | wc -l
414
$ grep -rwn CONFIG_X86_64 linux-3.15.3/arch/x86/ | wc -l
472
$ grep -rn 'def.*CONFIG_X86_32' linux-3.15.3/arch/x86/ | wc -l
341
$ grep -rn 'def.*CONFIG_X86_64' linux-3.15.3/arch/x86/ | wc -l
403
$ find linux-3.15.3/arch/x86/ -name '*_32.[ch]' | wc -l
59
$ find linux-3.15.3/arch/x86/ -name '*_64.[ch]' | wc -l
61
$ find linux-3.15.3/arch/x86/ -name '*_32.[chS]' | wc -l
81
$ find linux-3.15.3/arch/x86/ -name '*_64.[chS]' | wc -l
101

so after several years(!) of effort there're almost as many exceptions as 'unified' files, or in other words, it wasn't done because i386/amd64 are the same arch (which is, ironically, something you'd know yourself if you *actually* worked with these archs). so you tell me who's treating marketing BS as a gospel of truth.