1# UML uses the generic IRQ sugsystem 2config GENERIC_HARDIRQS 3 bool 4 default y 5 6config UML 7 bool 8 default y 9 10config MMU 11 bool 12 default y 13 14mainmenu "Linux/Usermode Kernel Configuration" 15 16config ISA 17 bool 18 19config SBUS 20 bool 21 22config PCI 23 bool 24 25config PCMCIA 26 bool 27 28config GENERIC_CALIBRATE_DELAY 29 bool 30 default y 31 32# Used in kernel/irq/manage.c and include/linux/irq.h 33config IRQ_RELEASE_METHOD 34 bool 35 default y 36 37menu "UML-specific options" 38 39config MODE_TT 40 bool "Tracing thread support" 41 default n 42 help 43 This option controls whether tracing thread support is compiled 44 into UML. This option is largely obsolete, given that skas0 provides 45 skas security and performance without needing to patch the host. 46 It is safe to say 'N' here. 47 48config STATIC_LINK 49 bool "Force a static link" 50 default n 51 depends on !MODE_TT 52 help 53 If CONFIG_MODE_TT is disabled, then this option gives you the ability 54 to force a static link of UML. Normally, if only skas mode is built 55 in to UML, it will be linked as a shared binary. This is inconvenient 56 for use in a chroot jail. So, if you intend to run UML inside a 57 chroot, and you disable CONFIG_MODE_TT, you probably want to say Y 58 here. 59 60config HOST_2G_2G 61 bool "2G/2G host address space split" 62 default n 63 depends on MODE_TT 64 help 65 This is needed when the host on which you run has a 2G/2G memory 66 split, instead of the customary 3G/1G. 67 68 Note that to enable such a host 69 configuration, which makes sense only in some cases, you need special 70 host patches. 71 72 So, if you do not know what to do here, say 'N'. 73 74config KERNEL_HALF_GIGS 75 int "Kernel address space size (in .5G units)" 76 default "1" 77 depends on MODE_TT 78 help 79 This determines the amount of address space that UML will allocate for 80 its own, measured in half Gigabyte units. The default is 1. 81 Change this only if you need to boot UML with an unusually large amount 82 of physical memory. 83 84config MODE_SKAS 85 bool "Separate Kernel Address Space support" if MODE_TT 86 default y 87 help 88 This option controls whether skas (separate kernel address space) 89 support is compiled in. If you have applied the skas patch to the 90 host, then you certainly want to say Y here (and consider saying N 91 to CONFIG_MODE_TT). Otherwise, it is safe to say Y. Disabling this 92 option will shrink the UML binary slightly. 93 94source "arch/um/Kconfig.arch" 95source "mm/Kconfig" 96 97config LD_SCRIPT_STATIC 98 bool 99 default y 100 depends on MODE_TT || STATIC_LINK 101 102config LD_SCRIPT_DYN 103 bool 104 default y 105 depends on !LD_SCRIPT_STATIC 106 107config NET 108 bool "Networking support" 109 help 110 Unless you really know what you are doing, you should say Y here. 111 The reason is that some programs need kernel networking support even 112 when running on a stand-alone machine that isn't connected to any 113 other computer. If you are upgrading from an older kernel, you 114 should consider updating your networking tools too because changes 115 in the kernel and the tools often go hand in hand. The tools are 116 contained in the package net-tools, the location and version number 117 of which are given in <file:Documentation/Changes>. 118 119 For a general introduction to Linux networking, it is highly 120 recommended to read the NET-HOWTO, available from 121 <http://www.tldp.org/docs.html#howto>. 122 123 124source "fs/Kconfig.binfmt" 125 126config HOSTFS 127 tristate "Host filesystem" 128 help 129 While the User-Mode Linux port uses its own root file system for 130 booting and normal file access, this module lets the UML user 131 access files stored on the host. It does not require any 132 network connection between the Host and UML. An example use of 133 this might be: 134 135 mount none /tmp/fromhost -t hostfs -o /tmp/umlshare 136 137 where /tmp/fromhost is an empty directory inside UML and 138 /tmp/umlshare is a directory on the host with files the UML user 139 wishes to access. 140 141 For more information, see 142 <http://user-mode-linux.sourceforge.net/hostfs.html>. 143 144 If you'd like to be able to work with files stored on the host, 145 say Y or M here; otherwise say N. 146 147config HPPFS 148 tristate "HoneyPot ProcFS (EXPERIMENTAL)" 149 depends on EXPERIMENTAL 150 help 151 hppfs (HoneyPot ProcFS) is a filesystem which allows UML /proc 152 entries to be overridden, removed, or fabricated from the host. 153 Its purpose is to allow a UML to appear to be a physical machine 154 by removing or changing anything in /proc which gives away the 155 identity of a UML. 156 157 See <http://user-mode-linux.sf.net/hppfs.html> for more information. 158 159 You only need this if you are setting up a UML honeypot. Otherwise, 160 it is safe to say 'N' here. 161 162config MCONSOLE 163 bool "Management console" 164 default y 165 help 166 The user mode linux management console is a low-level interface to 167 the kernel, somewhat like the i386 SysRq interface. Since there is 168 a full-blown operating system running under every user mode linux 169 instance, there is much greater flexibility possible than with the 170 SysRq mechanism. 171 172 If you answer 'Y' to this option, to use this feature, you need the 173 mconsole client (called uml_mconsole) which is present in CVS in 174 2.4.5-9um and later (path /tools/mconsole), and is also in the 175 distribution RPM package in 2.4.6 and later. 176 177 It is safe to say 'Y' here. 178 179config MAGIC_SYSRQ 180 bool "Magic SysRq key" 181 depends on MCONSOLE 182 ---help--- 183 If you say Y here, you will have some control over the system even 184 if the system crashes for example during kernel debugging (e.g., you 185 will be able to flush the buffer cache to disk, reboot the system 186 immediately or dump some status information). A key for each of the 187 possible requests is provided. 188 189 This is the feature normally accomplished by pressing a key 190 while holding SysRq (Alt+PrintScreen). 191 192 On UML, this is accomplished by sending a "sysrq" command with 193 mconsole, followed by the letter for the requested command. 194 195 The keys are documented in <file:Documentation/sysrq.txt>. Don't say Y 196 unless you really know what this hack does. 197 198config SMP 199 bool "Symmetric multi-processing support (EXPERIMENTAL)" 200 default n 201 #SMP_BROKEN is for x86_64. 202 depends on MODE_TT && EXPERIMENTAL && (!SMP_BROKEN || (BROKEN && SMP_BROKEN)) 203 help 204 This option enables UML SMP support. 205 It is NOT related to having a real SMP box. Not directly, at least. 206 207 UML implements virtual SMP by allowing as many processes to run 208 simultaneously on the host as there are virtual processors configured. 209 210 Obviously, if the host is a uniprocessor, those processes will 211 timeshare, but, inside UML, will appear to be running simultaneously. 212 If the host is a multiprocessor, then UML processes may run 213 simultaneously, depending on the host scheduler. 214 215 This, however, is supported only in TT mode. So, if you use the SKAS 216 patch on your host, switching to TT mode and enabling SMP usually gives 217 you worse performances. 218 Also, since the support for SMP has been under-developed, there could 219 be some bugs being exposed by enabling SMP. 220 221 If you don't know what to do, say N. 222 223config NR_CPUS 224 int "Maximum number of CPUs (2-32)" 225 range 2 32 226 depends on SMP 227 default "32" 228 229config NEST_LEVEL 230 int "Nesting level" 231 default "0" 232 help 233 This is set to the number of layers of UMLs that this UML will be run 234 in. Normally, this is zero, meaning that it will run directly on the 235 host. Setting it to one will build a UML that can run inside a UML 236 that is running on the host. Generally, if you intend this UML to run 237 inside another UML, set CONFIG_NEST_LEVEL to one more than the host 238 UML. 239 240 Note that if the hosting UML has its CONFIG_KERNEL_HALF_GIGS set to 241 greater than one, then the guest UML should have its CONFIG_NEST_LEVEL 242 set to the host's CONFIG_NEST_LEVEL + CONFIG_KERNEL_HALF_GIGS. 243 Only change this if you are running nested UMLs. 244 245config HIGHMEM 246 bool "Highmem support (EXPERIMENTAL)" 247 depends on !64BIT && EXPERIMENTAL 248 default n 249 help 250 This was used to allow UML to run with big amounts of memory. 251 Currently it is unstable, so if unsure say N. 252 253 To use big amounts of memory, it is recommended to disable TT mode (i.e. 254 CONFIG_MODE_TT) and enable static linking (i.e. CONFIG_STATIC_LINK) - 255 this should allow the guest to use up to 2.75G of memory. 256 257config KERNEL_STACK_ORDER 258 int "Kernel stack size order" 259 default 2 260 help 261 This option determines the size of UML kernel stacks. They will 262 be 1 << order pages. The default is OK unless you're running Valgrind 263 on UML, in which case, set this to 3. 264 265config UML_REAL_TIME_CLOCK 266 bool "Real-time Clock" 267 default y 268 help 269 This option makes UML time deltas match wall clock deltas. This should 270 normally be enabled. The exception would be if you are debugging with 271 UML and spend long times with UML stopped at a breakpoint. In this 272 case, when UML is restarted, it will call the timer enough times to make 273 up for the time spent at the breakpoint. This could result in a 274 noticable lag. If this is a problem, then disable this option. 275 276endmenu 277 278source "init/Kconfig" 279 280source "drivers/block/Kconfig" 281 282source "arch/um/Kconfig.char" 283 284source "drivers/base/Kconfig" 285 286source "net/Kconfig" 287 288source "arch/um/Kconfig.net" 289 290source "drivers/net/Kconfig" 291 292source "drivers/connector/Kconfig" 293 294source "fs/Kconfig" 295 296source "security/Kconfig" 297 298source "crypto/Kconfig" 299 300source "lib/Kconfig" 301 302menu "SCSI support" 303depends on BROKEN 304 305config SCSI 306 tristate "SCSI support" 307 308# This gives us free_dma, which scsi.c wants. 309config GENERIC_ISA_DMA 310 bool 311 depends on SCSI 312 default y 313 314source "arch/um/Kconfig.scsi" 315 316endmenu 317 318source "drivers/md/Kconfig" 319 320if BROKEN 321 source "drivers/mtd/Kconfig" 322endif 323 324#This is just to shut up some Kconfig warnings, so no prompt. 325config INPUT 326 bool 327 default n 328 329source "arch/um/Kconfig.debug" 330