On 04/10/2013 07:40 PM, Simon Jeons wrote: > Hi H.Peter, > On 04/04/2013 09:13 AM, H. Peter Anvin wrote: >> On 04/03/2013 06:11 PM, Simon Jeons wrote: >>> Why we consider boot_cpu_data.x86_phys_bits instead of e820 map here? >>> >> Because x86_phys_bits is what controls how much address space the >> processor has. e820 tells us how much *RAM* the machine has, or >> specifically, how much RAM the machine had on boot. > > I have 8GB memory in my machine, but when I accumulated every e820 > ranges which dump in dmesg, there are 25MB memory less then 8GB(1024*8) > memory, why 25MB miss? > For whatever reason your BIOS is stealing some memory, possibly for video. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>