Edit File: Kconfig.um
config STATIC_LINK bool "Force a static link" default n help This option gives you the ability to force a static link of UML. Normally, UML is linked as a shared binary. This is inconvenient for use in a chroot jail. So, if you intend to run UML inside a chroot, you probably want to say Y here. Additionally, this option enables using higher memory spaces (up to 2.75G) for UML. source "mm/Kconfig" config LD_SCRIPT_STATIC bool default y depends on STATIC_LINK config LD_SCRIPT_DYN bool default y depends on !LD_SCRIPT_STATIC source "fs/Kconfig.binfmt" config HOSTFS tristate "Host filesystem" help While the User-Mode Linux port uses its own root file system for booting and normal file access, this module lets the UML user access files stored on the host. It does not require any network connection between the Host and UML. An example use of this might be: mount none /tmp/fromhost -t hostfs -o /tmp/umlshare where /tmp/fromhost is an empty directory inside UML and /tmp/umlshare is a directory on the host with files the UML user wishes to access. For more information, see <http://user-mode-linux.sourceforge.net/hostfs.html>. If you'd like to be able to work with files stored on the host, say Y or M here; otherwise say N. config HPPFS tristate "HoneyPot ProcFS" depends on PROC_FS help hppfs (HoneyPot ProcFS) is a filesystem which allows UML /proc entries to be overridden, removed, or fabricated from the host. Its purpose is to allow a UML to appear to be a physical machine by removing or changing anything in /proc which gives away the identity of a UML. See <http://user-mode-linux.sf.net/old/hppfs.html> for more information. You only need this if you are setting up a UML honeypot. Otherwise, it is safe to say 'N' here. config MCONSOLE bool "Management console" default y help The user mode linux management console is a low-level interface to the kernel, somewhat like the i386 SysRq interface. Since there is a full-blown operating system running under every user mode linux instance, there is much greater flexibility possible than with the SysRq mechanism. If you answer 'Y' to this option, to use this feature, you need the mconsole client (called uml_mconsole) which is present in CVS in 2.4.5-9um and later (path /tools/mconsole), and is also in the distribution RPM package in 2.4.6 and later. It is safe to say 'Y' here. config MAGIC_SYSRQ bool "Magic SysRq key" depends on MCONSOLE help If you say Y here, you will have some control over the system even if the system crashes for example during kernel debugging (e.g., you will be able to flush the buffer cache to disk, reboot the system immediately or dump some status information). A key for each of the possible requests is provided. This is the feature normally accomplished by pressing a key while holding SysRq (Alt+PrintScreen). On UML, this is accomplished by sending a "sysrq" command with mconsole, followed by the letter for the requested command. The keys are documented in <file:Documentation/sysrq.txt>. Don't say Y unless you really know what this hack does. config SMP bool "Symmetric multi-processing support" default n depends on BROKEN help This option enables UML SMP support. It is NOT related to having a real SMP box. Not directly, at least. UML implements virtual SMP by allowing as many processes to run simultaneously on the host as there are virtual processors configured. Obviously, if the host is a uniprocessor, those processes will timeshare, but, inside UML, will appear to be running simultaneously. If the host is a multiprocessor, then UML processes may run simultaneously, depending on the host scheduler. This, however, is supported only in TT mode. So, if you use the SKAS patch on your host, switching to TT mode and enabling SMP usually gives you worse performances. Also, since the support for SMP has been under-developed, there could be some bugs being exposed by enabling SMP. If you don't know what to do, say N. config NR_CPUS int "Maximum number of CPUs (2-32)" range 2 32 depends on SMP default "32" config HIGHMEM bool "Highmem support" depends on !64BIT && BROKEN default n help This was used to allow UML to run with big amounts of memory. Currently it is unstable, so if unsure say N. To use big amounts of memory, it is recommended enable static linking (i.e. CONFIG_STATIC_LINK) - this should allow the guest to use up to 2.75G of memory. config KERNEL_STACK_ORDER int "Kernel stack size order" default 1 if 64BIT range 1 10 if 64BIT default 0 if !64BIT help This option determines the size of UML kernel stacks. They will be 1 << order pages. The default is OK unless you're running Valgrind on UML, in which case, set this to 3. config MMAPPER tristate "iomem emulation driver" help This driver allows a host file to be used as emulated IO memory inside UML. config NO_DMA def_bool y