map_user_kiobuf returns duplicate pages

lee_merrill_at_yahoo.com
Date: 05/27/05

  • Next message: Grant Edwards: "Re: immediate receiving of data from serial interfaces" 
    Date: 27 May 2005 14:37:42 -0700

    Hi everyone,

    I am calling map_user_kiobuf() to map approximately 64K of a user's
    stack into kernel memory, and I get the same page returned for about 8
    of the page entries, and I'm wondering how on earth this could happen.

    Any thoughts on this would be appreciated...

    Thanks,
    Lee

    P.S. Here is a printout of the number of bytes I requested, the number
    of bytes and pages after map_user_kiobuf() returns, and the page table
    pointers and what kmap() returns for each page table pointer.

    May 27 15:37:58 zdasd2 kernel: mapIobuf: 66035/66035 bytes, 17 pages
    May 27 15:37:58 zdasd2 kernel: mapIobuf: kmap 0 - C1705350 to
    0xE017C000
    May 27 15:37:58 zdasd2 kernel: mapIobuf: kmap 1 - C1003910 to
    0xC0104000
    May 27 15:37:58 zdasd2 kernel: mapIobuf: kmap 2 - C1003910 to
    0xC0104000
    May 27 15:37:58 zdasd2 kernel: mapIobuf: kmap 3 - C1003910 to
    0xC0104000
    May 27 15:37:58 zdasd2 kernel: mapIobuf: kmap 4 - C1003910 to
    0xC0104000
    May 27 15:37:58 zdasd2 kernel: mapIobuf: kmap 5 - C1003910 to
    0xC0104000
    May 27 15:37:58 zdasd2 kernel: mapIobuf: kmap 6 - C1705430 to
    0xE0180000
    May 27 15:37:58 zdasd2 kernel: mapIobuf: kmap 7 - C1003910 to
    0xC0104000
    May 27 15:37:58 zdasd2 kernel: mapIobuf: kmap 8 - C1003910 to
    0xC0104000
    May 27 15:37:58 zdasd2 kernel: mapIobuf: kmap 9 - C1003910 to
    0xC0104000
    May 27 15:37:58 zdasd2 kernel: mapIobuf: kmap 10 - C1003910 to
    0xC0104000
    May 27 15:37:58 zdasd2 kernel: mapIobuf: kmap 11 - C1003910 to
    0xC0104000
    May 27 15:37:58 zdasd2 kernel: mapIobuf: kmap 12 - C1003910 to
    0xC0104000
    May 27 15:37:58 zdasd2 kernel: mapIobuf: kmap 13 - C1003910 to
    0xC0104000
    May 27 15:37:58 zdasd2 kernel: mapIobuf: kmap 14 - C1705468 to
    0xE0181000
    May 27 15:37:58 zdasd2 kernel: mapIobuf: kmap 15 - C1705858 to
    0xE0193000
    May 27 15:37:58 zdasd2 kernel: mapIobuf: kmap 16 - C1708878 to
    0xE026F000

  • Next message: Grant Edwards: "Re: immediate receiving of data from serial interfaces"

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