Re: syscall __NR_mmap2

[Ulrich Drepper]

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Richard B. Johnson wrote:

> write(1, "Addr = 000b8000\n", 16)       = 16
> open("/dev/mem", O_RDWR)                = 3
> mmap2(0xb8000, 8192, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_FIXED, 3, 0xb8000) = 0xb8000

mmap64() (and if you compile glibc with an adequate minimal kernel
requirement mmap as well) is implemented using mmap2.  It works nicely.
 Admittedly, I haven't used the stock 2.4 kernel.  And I also haven't
used /dev/mem.  But at least for the first part I would expect to see
problem reports since the code is used and glibc wouldn't work.

In your code, assuming this is x86, do you really want to read the
memory starting at address 0xb8000000?  This is what your code does.  I
don't know enough about the kernel memory layout to say whether
something is supposed to be there or not.

- -- 
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Ulrich Drepper \    ,-----------------'   \ Mountain View, CA 94041 USA
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