lkml.org 
[lkml]   [2010]   [Jun]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH 2/4] x86: ioremap: fix physical address check
    On 06/13/2010 11:38 PM, Maciej W. Rozycki wrote:
    > On Mon, 14 Jun 2010, Kenji Kaneshige wrote:
    >
    >> - Architectural limit of physical address in x86 32-bit mode is 40-bit
    >> (depnds on processor version).
    >
    > According to documentation I happen to have handy this limit is actually
    > 52 bits (and space is currently available in the data structures used for
    > a possible future extension up to 63 bits).
    >

    Yes. There are, however, very likely bugs in several classes due to
    incorrect bitmasks as well as 32-bit PFNs.

    We have made the decision based on data structure limitations (and just
    usability) to not support more than 2^36 bytes of RAM on 32 bits, but
    those data structures should not affect I/O. I;d like to track down and
    fix the bugs instead of papering over the problem...

    -hpa

    --
    H. Peter Anvin, Intel Open Source Technology Center
    I work for Intel. I don't speak on their behalf.



    \
     
     \ /
      Last update: 2010-06-14 17:15    [W:0.020 / U:89.964 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site