On Sun, Feb 24, 2013 at 11:23 PM, [off-list ref] wrote:

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

quoted

   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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