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    SubjectRe: Illegal use of reserved word in system.h
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    On Thu, 2005-05-19 at 15:43 +0100, Maciej W. Rozycki wrote:
    > On Thu, 19 May 2005, Steven Rostedt wrote:
    >
    > > > See create_elf_tables. The aux table comes after the environment.
    > >
    > > As I stated earlier, the page size passed in there is ELF_EXEC_PAGESIZE
    > > which may not be the same as PAGE_SIZE.
    >
    > Well, AT_PAGESZ is specified as "system page size". If we pass something
    > else, then it's asking for troubles. What comes from AT_PAGESZ is used by
    > userland for stuff like masking arguments for mmap() and mprotect() so
    > it'd better be the right value.

    Well, they probably are the same, but then what's the reason for the
    lines in binfmt_elf.c:

    #if ELF_EXEC_PAGESIZE > PAGE_SIZE
    # define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE
    #else
    # define ELF_MIN_ALIGN PAGE_SIZE
    #endif


    This looks to me that ELF_EXEC_PAGESIZE and PAGE_SIZE may not be the
    same. And what's passed to AT_PAGESZ is ELF_EXEC_PAGESIZE. In mips (as
    your email address shows you are interested in) ELF_EXEC_PAGESIZE is
    simply defined as PAGE_SIZE. But in intel i386, it is defined as 4096,
    which coincidentally is the same as PAGE_SIZE but there's no guarantee
    that this will be the same, unless who ever changes PAGE_SIZE also
    remembers to change ELF_EXEC_PAGESIZE.

    In arm26 the PAGE_SIZE is configurable (16k or 32k) but the
    ELF_EXEC_PAGESIZE stays as 32k. So is this a bug?

    -- Steve


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