Ingo Molnar wrote: > * Yinghai Lu <yinghai@xxxxxxxxxx> wrote: > >> one system with 4g installed ( there is 1g hole) >> >> when 4G installed. >> BIOS put ACPI etc need the hole >> [ 0.000000] BIOS-provided physical RAM map: >> [ 0.000000] BIOS-e820: 0000000000000000 - 000000000009bc00 (usable) >> [ 0.000000] BIOS-e820: 000000000009bc00 - 00000000000a0000 (reserved) >> [ 0.000000] BIOS-e820: 00000000000e3000 - 0000000000100000 (reserved) >> [ 0.000000] BIOS-e820: 0000000000100000 - 00000000bffa0000 (usable) >> [ 0.000000] BIOS-e820: 00000000bffa0000 - 00000000bffae000 (ACPI data) >> [ 0.000000] BIOS-e820: 00000000bffae000 - 00000000bfff0000 (ACPI NVS) >> [ 0.000000] BIOS-e820: 00000000bfff0000 - 00000000c0000000 (reserved) >> [ 0.000000] BIOS-e820: 00000000fee00000 - 00000000fee01000 (reserved) >> [ 0.000000] BIOS-e820: 00000000ffb00000 - 0000000100000000 (reserved) >> [ 0.000000] BIOS-e820: 0000000100000000 - 0000000140000000 (usable) >> so in kernel resource will be reserved for 0xbffa0000 - 0xbfff0000 for ACPI >> 0x100000 - 0xbffa0000 for RAM... > > btw., sidenote, it would be nice to enhance the e820 table printout > with size and hole info as well. I did this manually yesterday in > another mail: > > BIOS-provided physical RAM map: > BIOS-e820: 0000000000000000 - 000000000009fc00 (usable) 0.639 MB RAM > BIOS-e820: 000000000009fc00 - 00000000000a0000 (reserved) 0.001 MB > [ hole ] 0.250 MB > BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved) 0.125 MB > BIOS-e820: 0000000000100000 - 000000003ed94000 (usable) 1004.5 MB RAM > BIOS-e820: 000000003ed94000 - 000000003ee4e000 (ACPI NVS) 0.7 MB > BIOS-e820: 000000003ee4e000 - 000000003fea2000 (usable) 16.3 MB RAM > BIOS-e820: 000000003fea2000 - 000000003fee9000 (ACPI NVS) 0.3 MB > BIOS-e820: 000000003fee9000 - 000000003feed000 (usable) 0.15 MB RAM > BIOS-e820: 000000003feed000 - 000000003feff000 (ACPI data 0.07 MB > BIOS-e820: 000000003feff000 - 000000003ff00000 (usable) 0.004 MB RAM > [ hole ] 1.0 MB > [ hole ] 3072.0 MB > > it would be extremely useful to have that in the printout, to see > the physical address space layout at a glance. Small holes are easy > to miss, and e820 entry sizes are hard to judge at a glance. > > To make this fit well, i'd suggest to drop the 'BIOS-e820: ' prefix > - it's redundant. will look at it. and should be another patch for x86. YH -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
