bugThe GNU Hurd - Bugs: bug #17346, GNU mach can't handle 4GB memory


bug #17346: GNU mach can't handle 4GB memory

Submitted by:  Samuel Thibault <sthibaul>
Submitted on:  Mon 07 Aug 2006 01:32:46 AM UTC  
Category:  GNU Mach Severity:  3 - Normal
Priority:  5 - Normal Item Group:  Hardware Support
Status:  Fixed Privacy:  Public
Assigned to:  None Originator Name: 
Open/Closed:  Closed Reproducibility:  Every Time
Size (loc):  None Planned Release:  None
Effort:  0.00
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Mon 20 Nov 2006 12:56:48 AM UTC, comment #2:

This better?

vm_size_t memsize = boot_info.mem_upper;

if ((memsize >= 0x400000))
memsize = (0x400000-1);

phys_last_addr = 0x100000 + (memsize * 0x400);

Barry deFreese <bddebian>
Thu 16 Nov 2006 05:35:21 PM UTC, comment #1:

Does it make sense to just do this in i386/i386at/model_dep.c:

/* Gnumach can't map more than 1GB so if over 1GB,
truncate it to 1GB - 1MB. */

if ((boot_info.mem_upper >= 0x100000))
boot_info.mem_upper = (0x100000 - 0x400);

Barry deFreese <bddebian>
Mon 07 Aug 2006 01:32:46 AM UTC, original submission:

Or more precisely, it roughly takes the memory size modulo 4GB. That's because in i386/i386at/model_dep.c, memory size computing is done with ints, i.e. 32bit values, hence the modulo 2^32. An quick fix would be to truncate boot_info's memory size reporting to 1GB, i.e. boot_info.mem_upper to (2^32-1MB)/0x400.

Samuel Thibault <sthibaul>
Project Member


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    Follow 6 latest changes.

    Date Changed by Updated Field Previous Value => Replaced by
    Sun 26 Nov 2006 08:08:46 PM UTC sthibaul StatusNone => Fixed
        Open/ClosedOpen => Closed
    Wed 15 Nov 2006 10:07:32 PM UTC sthibaul StatusFixed => None
        Open/ClosedClosed => Open
    Wed 15 Nov 2006 10:05:36 PM UTC sthibaul Open/ClosedOpen => Closed
    Wed 15 Nov 2006 10:05:35 PM UTC sthibaul StatusNone => Fixed

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