linux-kernel - 4GB Physical. Less than 3GB in Linux.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 16 Apr 2007 15:28:21 +0800
From:	"Jeff Chua" <jeff.chua.linux@...il.com>
To:	lkml <linux-kernel@...r.kernel.org>
Subject: 4GB Physical. Less than 3GB in Linux.

I've noticed that with 4GB physical ram, I'm only see 3098000 MB on
the Dell 745, and 3107056MB on the IBM X60s.

I've tested with CONFIG_HIGHMEM4G=y, CONFIG_HIGHMEM64G=y,
CONFIG_X86_PAE=y, but nothing makes any difference.

Tested on Linux 2.6.20, Linux 2.6.21-rc7.

# dmesg
copy_e820_map() start: 0000000000000000 size: 000000000009f000 end:
000000000009f000 type: 1
copy_e820_map() type is E820_RAM
copy_e820_map() start: 000000000009f000 size: 0000000000001000 end:
00000000000a0000 type: 2
copy_e820_map() start: 00000000000dc000 size: 0000000000024000 end:
0000000000100000 type: 2
copy_e820_map() start: 0000000000100000 size: 00000000bf5d0000 end:
00000000bf6d0000 type: 1
copy_e820_map() type is E820_RAM
copy_e820_map() start: 00000000bf6d0000 size: 000000000000f000 end:
00000000bf6df000 type: 3
copy_e820_map() start: 00000000bf6df000 size: 0000000000021000 end:
00000000bf700000 type: 4
copy_e820_map() start: 00000000bf700000 size: 0000000000900000 end:
00000000c0000000 type: 2
copy_e820_map() start: 00000000f0000000 size: 0000000004000000 end:
00000000f4000000 type: 2
copy_e820_map() start: 00000000fec00000 size: 0000000000010000 end:
00000000fec10000 type: 2
copy_e820_map() start: 00000000fed00000 size: 0000000000000400 end:
00000000fed00400 type: 2
copy_e820_map() start: 00000000fed14000 size: 0000000000006000 end:
00000000fed1a000 type: 2
copy_e820_map() start: 00000000fed1c000 size: 0000000000074000 end:
00000000fed90000 type: 2
copy_e820_map() start: 00000000fee00000 size: 0000000000001000 end:
00000000fee01000 type: 2
copy_e820_map() start: 00000000ff800000 size: 0000000000800000 end:
0000000100000000 type: 2
 BIOS-e820: 0000000000000000 - 000000000009f000 (usable)
 BIOS-e820: 000000000009f000 - 00000000000a0000 (reserved)
 BIOS-e820: 00000000000dc000 - 0000000000100000 (reserved)
 BIOS-e820: 0000000000100000 - 00000000bf6d0000 (usable)
 BIOS-e820: 00000000bf6d0000 - 00000000bf6df000 (ACPI data)
 BIOS-e820: 00000000bf6df000 - 00000000bf700000 (ACPI NVS)
 BIOS-e820: 00000000bf700000 - 00000000c0000000 (reserved)
 BIOS-e820: 00000000f0000000 - 00000000f4000000 (reserved)
 BIOS-e820: 00000000fec00000 - 00000000fec10000 (reserved)
 BIOS-e820: 00000000fed00000 - 00000000fed00400 (reserved)
 BIOS-e820: 00000000fed14000 - 00000000fed1a000 (reserved)
 BIOS-e820: 00000000fed1c000 - 00000000fed90000 (reserved)
 BIOS-e820: 00000000fee00000 - 00000000fee01000 (reserved)
 BIOS-e820: 00000000ff800000 - 0000000100000000 (reserved)
2166MB HIGHMEM available.
896MB LOWMEM available.

Memory: 3106140k/3136320k available (2225k kernel code, 29072k
reserved, 910k data, 196k init, 2218816k highmem)
virtual kernel memory layout:
    fixmap  : 0xfff50000 - 0xfffff000   ( 700 kB)
    pkmap   : 0xff800000 - 0xffc00000   (4096 kB)
    vmalloc : 0xf8800000 - 0xff7fe000   ( 111 MB)
    lowmem  : 0xc0000000 - 0xf8000000   ( 896 MB)
      .init : 0xc0416000 - 0xc0447000   ( 196 kB)
      .data : 0xc032c513 - 0xc040ff34   ( 910 kB)
      .text : 0xc0100000 - 0xc032c513   (2225 kB)


Thanks,
Jeff.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/