summaryrefslogtreecommitdiffstats
path: root/arch/um/Kconfig
diff options
context:
space:
mode:
Diffstat (limited to 'arch/um/Kconfig')
-rw-r--r--arch/um/Kconfig190
1 files changed, 190 insertions, 0 deletions
diff --git a/arch/um/Kconfig b/arch/um/Kconfig
new file mode 100644
index 000000000..6b9938919
--- /dev/null
+++ b/arch/um/Kconfig
@@ -0,0 +1,190 @@
+# SPDX-License-Identifier: GPL-2.0
+
+menu "UML-specific options"
+
+config UML
+ bool
+ default y
+ select ARCH_HAS_KCOV
+ select ARCH_NO_PREEMPT
+ select HAVE_ARCH_AUDITSYSCALL
+ select HAVE_ARCH_SECCOMP_FILTER
+ select HAVE_UID16
+ select HAVE_FUTEX_CMPXCHG if FUTEX
+ select HAVE_DEBUG_KMEMLEAK
+ select GENERIC_IRQ_SHOW
+ select GENERIC_CPU_DEVICES
+ select GENERIC_CLOCKEVENTS
+ select HAVE_GCC_PLUGINS
+ select TTY # Needed for line.c
+
+config MMU
+ bool
+ default y
+
+config NO_IOMEM
+ def_bool y
+
+config ISA
+ bool
+
+config SBUS
+ bool
+
+config PCI
+ bool
+
+config PCMCIA
+ bool
+
+config TRACE_IRQFLAGS_SUPPORT
+ bool
+ default y
+
+config LOCKDEP_SUPPORT
+ bool
+ default y
+
+config STACKTRACE_SUPPORT
+ bool
+ default y
+ select STACKTRACE
+
+config GENERIC_CALIBRATE_DELAY
+ bool
+ default y
+
+config HZ
+ int
+ default 100
+
+config NR_CPUS
+ int
+ range 1 1
+ default 1
+
+source "arch/$(HEADER_ARCH)/um/Kconfig"
+
+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.
+
+config LD_SCRIPT_STATIC
+ bool
+ default y
+ depends on STATIC_LINK
+
+config LD_SCRIPT_DYN
+ bool
+ default y
+ depends on !LD_SCRIPT_STATIC
+ select MODULE_REL_CRCS if MODVERSIONS
+
+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 MCONSOLE
+ bool "Management console"
+ depends on PROC_FS
+ 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/admin-guide/sysrq.rst>. Don't say Y
+ unless you really know what this hack does.
+
+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
+
+config PGTABLE_LEVELS
+ int
+ default 3 if 3_LEVEL_PGTABLES
+ default 2
+
+config SECCOMP
+ def_bool y
+ prompt "Enable seccomp to safely compute untrusted bytecode"
+ ---help---
+ This kernel feature is useful for number crunching applications
+ that may need to compute untrusted bytecode during their
+ execution. By using pipes or other transports made available to
+ the process as file descriptors supporting the read/write
+ syscalls, it's possible to isolate those applications in
+ their own address space using seccomp. Once seccomp is
+ enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
+ and the task is only allowed to execute a few safe syscalls
+ defined by each seccomp mode.
+
+ If unsure, say Y.
+
+endmenu
+
+source "arch/um/drivers/Kconfig"