On Mon, Sep 2, 2013 at 4:41 PM, Stan Hoeppner <s...@hardwarefreak.com> wrote: > On 9/1/2013 9:44 PM, Joel Rees wrote: >> On Mon, Sep 2, 2013 at 7:18 AM, Pascal Hambourg <pas...@plouf.fr.eu.org> >> wrote: >>> Richard Owlett a écrit : >>>> Stan Hoeppner wrote: >>>>> >>>>> So I fail to see why your knowing the "CPU bus width" is relevant to >>>>> anything. >>>> >>>> If I understand correctly some processors can run 32 bit OSes but >>>> not any 64 bit OS. >>> >>> This has nothing to do with bus width. >> >> Not an entirely separate issue from the address bus width, however. > > While it's possible to back track a CPU's ISA from knowing the address > line width, there are far more practical and fool proof methods to > determining the ISA.
Really? I mean, for the un-initiate? >> Just for fun, I looked at what this box tells me with lscpu and >> cat-ting /proc/cpuinfo. The relevant lines in the reply are, for >> lscpu, >> >> CPU op-mode(s): 32-bit >> >> which tells me that it can run OSses in 32-bit mode, I think. > > You're making this harder than need be. Look at the 'flags' data in > /proc/cpuinfo. If you see 'lm' it's a 64 bit ISA CPU and can run a 64 > bit OS. If 'lm' is not present it's a 32 bit only CPU. 'lm' represents > "Long Mode" which is the operating mode of x86-64 processors that > enables execution of 64 bit instructions. > > -- > Stan Which is great if you happen to know that lm iin the flags means "long mode" and that "long" in this case means the ability to use and calculate "long=64 bit" addresses at a pace useful enough to run the 64 bit (addressing) OS. (And it's not just us old fogies. There are still a lot of contexts in which "long" still means 32 bit addresses. Just because Intel is trying to forget its roots doesn't mean the rest of the world is on their bandwagon.) -- Joel Rees -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/CAAr43iPhxR1DmbKEb=td3i_6bkgpnmt18jutvx5gojfsbhx...@mail.gmail.com
