@enumerate
@item
-Download the archive @file{vl-test-xxx.tar.gz} containing a Linux kernel
-and an initrd (initial Ram Disk). The archive also contains a
-precompiled version of @file{vl}, the QEMU System emulator.
+Download the archive @file{vl-test-xxx.tar.gz} containing a Linux
+kernel and a disk image. The archive also contains a precompiled
+version of @file{vl}, the QEMU System emulator.
@item Optional: If you want network support (for example to launch X11 examples), you
must copy the script @file{vl-ifup} in @file{/etc} and configure
> ./vl.sh
connected to host network interface: tun0
Uncompressing Linux... Ok, booting the kernel.
-Linux version 2.4.20 (bellard@voyager) (gcc version 2.95.2 20000220 (Debian GNU/Linux)) #42 Wed Jun 25 14:16:12 CEST 2003
+Linux version 2.4.20 (fabrice@localhost.localdomain) (gcc version 2.96 20000731 (Red Hat Linux 7.3 2.96-110)) #22 lun jui 7 13:37:41 CEST 2003
BIOS-provided physical RAM map:
- BIOS-88: 0000000000000000 - 000000000009f000 (usable)
- BIOS-88: 0000000000100000 - 0000000002000000 (usable)
+ BIOS-e801: 0000000000000000 - 000000000009f000 (usable)
+ BIOS-e801: 0000000000100000 - 0000000002000000 (usable)
32MB LOWMEM available.
On node 0 totalpages: 8192
zone(0): 4096 pages.
zone(1): 4096 pages.
zone(2): 0 pages.
-Kernel command line: root=/dev/ram ramdisk_size=6144
+Kernel command line: root=/dev/hda ide1=noprobe ide2=noprobe ide3=noprobe ide4=noprobe ide5=noprobe
+ide_setup: ide1=noprobe
+ide_setup: ide2=noprobe
+ide_setup: ide3=noprobe
+ide_setup: ide4=noprobe
+ide_setup: ide5=noprobe
Initializing CPU#0
-Detected 501.785 MHz processor.
-Calibrating delay loop... 973.20 BogoMIPS
-Memory: 24776k/32768k available (725k kernel code, 7604k reserved, 151k data, 48k init, 0k highmem)
+Detected 501.285 MHz processor.
+Calibrating delay loop... 989.59 BogoMIPS
+Memory: 29268k/32768k available (907k kernel code, 3112k reserved, 212k data, 52k init, 0k highmem)
Dentry cache hash table entries: 4096 (order: 3, 32768 bytes)
Inode cache hash table entries: 2048 (order: 2, 16384 bytes)
Mount-cache hash table entries: 512 (order: 0, 4096 bytes)
Initializing RT netlink socket
apm: BIOS not found.
Starting kswapd
+Journalled Block Device driver loaded
pty: 256 Unix98 ptys configured
Serial driver version 5.05c (2001-07-08) with no serial options enabled
ttyS00 at 0x03f8 (irq = 4) is a 16450
+Uniform Multi-Platform E-IDE driver Revision: 6.31
+ide: Assuming 50MHz system bus speed for PIO modes; override with idebus=xx
+hda: QEMU HARDDISK, ATA DISK drive
+ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
+hda: 12288 sectors (6 MB) w/256KiB Cache, CHS=12/16/63
+Partition check:
+ hda: unknown partition table
ne.c:v1.10 9/23/94 Donald Becker (becker@scyld.com)
Last modified Nov 1, 2000 by Paul Gortmaker
NE*000 ethercard probe at 0x300: 52 54 00 12 34 56
eth0: NE2000 found at 0x300, using IRQ 9.
-RAMDISK driver initialized: 16 RAM disks of 6144K size 1024 blocksize
+RAMDISK driver initialized: 16 RAM disks of 4096K size 1024 blocksize
NET4: Linux TCP/IP 1.0 for NET4.0
IP Protocols: ICMP, UDP, TCP, IGMP
IP: routing cache hash table of 512 buckets, 4Kbytes
-TCP: Hash tables configured (established 2048 bind 2048)
+TCP: Hash tables configured (established 2048 bind 4096)
NET4: Unix domain sockets 1.0/SMP for Linux NET4.0.
-RAMDISK: ext2 filesystem found at block 0
-RAMDISK: Loading 6144 blocks [1 disk] into ram disk... done.
-Freeing initrd memory: 6144k freed
+EXT2-fs warning: mounting unchecked fs, running e2fsck is recommended
VFS: Mounted root (ext2 filesystem).
-Freeing unused kernel memory: 48k freed
+Freeing unused kernel memory: 52k freed
sh: can't access tty; job control turned off
#
@end example
NOTES:
@enumerate
@item
-A 2.5.66 kernel is also included in the vl-test archive. Just
+A 2.5.74 kernel is also included in the vl-test archive. Just
replace the bzImage in vl.sh to try it.
@item
unnecessary disk accesses.
@item
-The example initrd is a modified version of the one made by Kevin
+In order to exit cleanly for vl, you can do a @emph{shutdown} inside
+vl. vl will automatically exit when the Linux shutdown is done.
+
+@item
+You can boot slightly faster by disabling the probe of non present IDE
+interfaces. To do so, add the following options on the kernel command
+line:
+@example
+ide1=noprobe ide2=noprobe ide3=noprobe ide4=noprobe ide5=noprobe
+@end example
+
+@item
+The example disk image is a modified version of the one made by Kevin
Lawton for the plex86 Project (@url{www.plex86.org}).
@end enumerate
General options:
@table @option
-@item -initrd file
-Use 'file' as initial ram disk.
-
@item -hda file
@item -hdb file
Use 'file' as hard disk 0 or 1 image (@xref{disk_images}).
Set network init script [default=/etc/vl-ifup]. This script is
launched to configure the host network interface (usually tun0)
corresponding to the virtual NE2000 card.
+
+@item -initrd file
+Use 'file' as initial ram disk.
@end table
Debug options:
modified time in the COW disk image so that chances of mistakes are
reduced.
-If raw disk image is not read-only, by pressing @key{C-a s} you can
-flush the COW disk image back into the raw disk image, as in snapshot
-mode.
+If the raw disk image is not read-only, by pressing @key{C-a s} you
+can flush the COW disk image back into the raw disk image, as in
+snapshot mode.
COW disk images can also be created without a corresponding raw disk
image. It is useful to have a big initial virtual disk image without
the real one. To know it, use the @code{ls -ls} command.
@end enumerate
-@section Kernel Compilation
+@section Linux Kernel Compilation
+
+You should be able to use any kernel with QEMU provided you make the
+following changes (only 2.4.x and 2.5.x were tested):
-You can use any Linux kernel within QEMU provided it is mapped at
-address 0x90000000 (the default is 0xc0000000). You must modify only two
-lines in the kernel source:
+@enumerate
+@item
+The kernel must be mapped at 0x90000000 (the default is
+0xc0000000). You must modify only two lines in the kernel source:
-In asm/page.h, replace
+In @file{include/asm/page.h}, replace
@example
#define __PAGE_OFFSET (0xc0000000)
@end example
#define __PAGE_OFFSET (0x90000000)
@end example
-And in arch/i386/vmlinux.lds, replace
+And in @file{arch/i386/vmlinux.lds}, replace
@example
. = 0xc0000000 + 0x100000;
@end example
. = 0x90000000 + 0x100000;
@end example
-The file config-2.4.20 gives the configuration of the example kernel.
-
-Just type
+@item
+If you want to enable SMP (Symmetric Multi-Processing) support, you
+must make the following change in @file{include/asm/fixmap.h}. Replace
@example
-make bzImage
+#define FIXADDR_TOP (0xffffX000UL)
@end example
+by
+@example
+#define FIXADDR_TOP (0xa7ffX000UL)
+@end example
+(X is 'e' or 'f' depending on the kernel version). Although you can
+use an SMP kernel with QEMU, it only supports one CPU.
-As you would do to make a real kernel. Then you can use with QEMU
-exactly the same kernel as you would boot on your PC (in
-@file{arch/i386/boot/bzImage}).
-
+@item
If you are not using a 2.5 kernel as host kernel but if you use a target
2.5 kernel, you must also ensure that the 'HZ' define is set to 100
(1000 is the default) as QEMU cannot currently emulate timers at
frequencies greater than 100 Hz on host Linux systems < 2.5. In
-asm/param.h, replace:
+@file{include/asm/param.h}, replace:
@example
# define HZ 1000 /* Internal kernel timer frequency */
# define HZ 100 /* Internal kernel timer frequency */
@end example
-If you have problems running your kernel, verify that neither the SMP nor
-HIGHMEM configuration options are activated.
+@end enumerate
+
+The file config-2.x.x gives the configuration of the example kernels.
+
+Just type
+@example
+make bzImage
+@end example
+
+As you would do to make a real kernel. Then you can use with QEMU
+exactly the same kernel as you would boot on your PC (in
+@file{arch/i386/boot/bzImage}).
@section PC Emulation
In order to use gdb, launch vl with the '-s' option. It will wait for a
gdb connection:
@example
-> vl -s arch/i386/boot/bzImage initrd-2.4.20.img root=/dev/ram0 ramdisk_size=6144
+> vl -s arch/i386/boot/bzImage -hda root-2.4.20.img root=/dev/hda
Connected to host network interface: tun0
Waiting gdb connection on port 1234
@end example
a linked list of every translated block contained in a given page. Other
linked lists are also maintained to undo direct block chaining.
-Althought the overhead of doing @code{mprotect()} calls is important,
+Although the overhead of doing @code{mprotect()} calls is important,
most MSDOS programs can be emulated at reasonnable speed with QEMU and
DOSEMU.
@section Self-virtualization
-QEMU was conceived so that ultimately it can emulate itself. Althought
+QEMU was conceived so that ultimately it can emulate itself. Although
it is not very useful, it is an important test to show the power of the
emulator.