Kconfig (79b05c1f31e2ed3dbc4e1d098a29687f5c39c495) Kconfig (f163977d21a2b380ef83c25df2f83740577dc564)
1# SPDX-License-Identifier: GPL-2.0
2
1# SPDX-License-Identifier: GPL-2.0
2
3menu "UML-specific options"
4
5config UML
6 bool
7 default y
8 select ARCH_HAS_KCOV
9 select HAVE_ARCH_AUDITSYSCALL
10 select HAVE_ARCH_SECCOMP_FILTER
11 select HAVE_UID16
12 select HAVE_FUTEX_CMPXCHG if FUTEX
13 select HAVE_DEBUG_KMEMLEAK
14 select GENERIC_IRQ_SHOW
15 select GENERIC_CPU_DEVICES
16 select GENERIC_CLOCKEVENTS
17 select HAVE_GCC_PLUGINS
18 select TTY # Needed for line.c
19
20config MMU
21 bool
22 default y
23
24config NO_IOMEM
25 def_bool y
26
27config ISA
28 bool
29
30config SBUS
31 bool
32
33config PCI
34 bool
35
36config PCMCIA
37 bool
38
39config TRACE_IRQFLAGS_SUPPORT
40 bool
41 default y
42
43config LOCKDEP_SUPPORT
44 bool
45 default y
46
47config STACKTRACE_SUPPORT
48 bool
49 default y
50 select STACKTRACE
51
52config GENERIC_CALIBRATE_DELAY
53 bool
54 default y
55
56config HZ
57 int
58 default 100
59
60config NR_CPUS
61 int
62 range 1 1
63 default 1
64
3source "arch/$(HEADER_ARCH)/um/Kconfig"
65source "arch/$(HEADER_ARCH)/um/Kconfig"
66
67config STATIC_LINK
68 bool "Force a static link"
69 default n
70 help
71 This option gives you the ability to force a static link of UML.
72 Normally, UML is linked as a shared binary. This is inconvenient for
73 use in a chroot jail. So, if you intend to run UML inside a chroot,
74 you probably want to say Y here.
75 Additionally, this option enables using higher memory spaces (up to
76 2.75G) for UML.
77
78source "mm/Kconfig"
79
80config LD_SCRIPT_STATIC
81 bool
82 default y
83 depends on STATIC_LINK
84
85config LD_SCRIPT_DYN
86 bool
87 default y
88 depends on !LD_SCRIPT_STATIC
89 select MODULE_REL_CRCS if MODVERSIONS
90
91source "fs/Kconfig.binfmt"
92
93config HOSTFS
94 tristate "Host filesystem"
95 help
96 While the User-Mode Linux port uses its own root file system for
97 booting and normal file access, this module lets the UML user
98 access files stored on the host. It does not require any
99 network connection between the Host and UML. An example use of
100 this might be:
101
102 mount none /tmp/fromhost -t hostfs -o /tmp/umlshare
103
104 where /tmp/fromhost is an empty directory inside UML and
105 /tmp/umlshare is a directory on the host with files the UML user
106 wishes to access.
107
108 For more information, see
109 <http://user-mode-linux.sourceforge.net/hostfs.html>.
110
111 If you'd like to be able to work with files stored on the host,
112 say Y or M here; otherwise say N.
113
114config MCONSOLE
115 bool "Management console"
116 depends on PROC_FS
117 default y
118 help
119 The user mode linux management console is a low-level interface to
120 the kernel, somewhat like the i386 SysRq interface. Since there is
121 a full-blown operating system running under every user mode linux
122 instance, there is much greater flexibility possible than with the
123 SysRq mechanism.
124
125 If you answer 'Y' to this option, to use this feature, you need the
126 mconsole client (called uml_mconsole) which is present in CVS in
127 2.4.5-9um and later (path /tools/mconsole), and is also in the
128 distribution RPM package in 2.4.6 and later.
129
130 It is safe to say 'Y' here.
131
132config MAGIC_SYSRQ
133 bool "Magic SysRq key"
134 depends on MCONSOLE
135 help
136 If you say Y here, you will have some control over the system even
137 if the system crashes for example during kernel debugging (e.g., you
138 will be able to flush the buffer cache to disk, reboot the system
139 immediately or dump some status information). A key for each of the
140 possible requests is provided.
141
142 This is the feature normally accomplished by pressing a key
143 while holding SysRq (Alt+PrintScreen).
144
145 On UML, this is accomplished by sending a "sysrq" command with
146 mconsole, followed by the letter for the requested command.
147
148 The keys are documented in <file:Documentation/admin-guide/sysrq.rst>. Don't say Y
149 unless you really know what this hack does.
150
151config KERNEL_STACK_ORDER
152 int "Kernel stack size order"
153 default 1 if 64BIT
154 range 1 10 if 64BIT
155 default 0 if !64BIT
156 help
157 This option determines the size of UML kernel stacks. They will
158 be 1 << order pages. The default is OK unless you're running Valgrind
159 on UML, in which case, set this to 3.
160
161config MMAPPER
162 tristate "iomem emulation driver"
163 help
164 This driver allows a host file to be used as emulated IO memory inside
165 UML.
166
167config NO_DMA
168 def_bool y
169
170config PGTABLE_LEVELS
171 int
172 default 3 if 3_LEVEL_PGTABLES
173 default 2
174
175config SECCOMP
176 def_bool y
177 prompt "Enable seccomp to safely compute untrusted bytecode"
178 ---help---
179 This kernel feature is useful for number crunching applications
180 that may need to compute untrusted bytecode during their
181 execution. By using pipes or other transports made available to
182 the process as file descriptors supporting the read/write
183 syscalls, it's possible to isolate those applications in
184 their own address space using seccomp. Once seccomp is
185 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
186 and the task is only allowed to execute a few safe syscalls
187 defined by each seccomp mode.
188
189 If unsure, say Y.
190
191endmenu
192
193source "init/Kconfig"
194
195source "kernel/Kconfig.freezer"
196
197source "arch/um/Kconfig.char"
198
199source "drivers/Kconfig"
200
201source "net/Kconfig"
202
203source "arch/um/Kconfig.net"
204
205source "fs/Kconfig"
206
207source "security/Kconfig"
208
209source "crypto/Kconfig"
210
211source "lib/Kconfig"
212
213source "arch/um/Kconfig.debug"