Re: valid address space ?

[Abu Rasheda <rcpilot2010@xxxxxxxxx>]

On Sun, Feb 24, 2013 at 11:23 PM, <Valdis.Kletnieks@xxxxxx> wrote:

On Sun, 24 Feb 2013 21:37:48 -0800, Abu Rasheda said:

>    tmp_long_ptr = ((long_ptr & 0x800000000000) ? (long_ptr |
> 0xffff800000000000) : (long_ptr & 0xFFFFFFFFFFFF));

This will not do what you think it does when compiled for a 32-bit
system.

This code will never run on 32 bit system, but on 64 bit Intel. So does this cover all possible valid addresses where kernel data structure can reside ? here is the _expression_ again:

 if (long_ptr > 0x1000)

  {

   tmp_long_ptr = ((long_ptr & 0x800000000000) ? (long_ptr | 0xffff800000000000) : (long_ptr & 0xFFFFFFFFFFFF));

printf("tmp_long_ptr :0x%llx\n", (long long int) tmp_long_ptr);

   if ((long_ptr == tmp_long_ptr) & (long_ptr >= 0x30000000))

      printf("valid 64 addr\n");

  }

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