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Dif. MTRR WC setting behavior under v86-question for Japheth (Developers)

posted by Japheth , Germany (South), 01.01.2019, 14:12

> Maybe there is some difference how CWSDPMI, DOS4GW and JEMM
> handles paging tables (if they touch them) and how physical address is
> mapped to linear address...

JEMM isn't involved, AFAICS, since it has no control of what bits a DPMI host might set in page tables.

You could try to use HDPMI instead of the DOS4GW DPMI host and see if that makes any difference. HDPMI doesn't set the "write through" or "cache disable" page table bits for DPMI function 0800h (map physical device).

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MS-DOS forever!

Complete thread:

• Dif. MTRR WC setting behavior under v86-question for Japheth - RayeR, 29.12.2018, 01:11 (Developers)
  • Dif. MTRR WC setting behavior under v86-question for Japheth - Japheth, 30.12.2018, 19:48
    • Dif. MTRR WC setting behavior under v86-question for Japheth - RayeR, 31.12.2018, 17:09
      • Dif. MTRR WC setting behavior under v86-question for Japheth - Japheth, 01.01.2019, 14:12
        • Dif. MTRR WC setting behavior under v86-question for Japheth - RayeR, 01.01.2019, 23:10
          • Dif. MTRR WC setting behavior under v86-question for Japheth - RayeR, 04.01.2019, 05:58
            • Dif. MTRR WC setting behavior under v86-question for Japheth - Laaca, 04.01.2019, 09:34
            • Dif. MTRR WC setting behavior under v86-question for Japheth - Japheth, 04.01.2019, 19:29
              • Dif. MTRR WC setting behavior under v86-question for Japheth - RayeR, 05.01.2019, 04:40