1menu "Kernel hacking" 2 3source "lib/Kconfig.debug" 4 5config PRINT_STACK_DEPTH 6 int "Stack depth to print" if DEBUG_KERNEL 7 default 64 8 help 9 This option allows you to set the stack depth that the kernel 10 prints in stack traces. This can be useful if your display is 11 too small and stack traces cause important information to 12 scroll off the screen. 13 14config DEBUG_STACKOVERFLOW 15 bool "Check for stack overflows" 16 depends on DEBUG_KERNEL 17 help 18 This option will cause messages to be printed if free stack space 19 drops below a certain limit. 20 21config DEBUG_STACK_USAGE 22 bool "Stack utilization instrumentation" 23 depends on DEBUG_KERNEL 24 help 25 Enables the display of the minimum amount of free stack which each 26 task has ever had available in the sysrq-T and sysrq-P debug output. 27 28 This option will slow down process creation somewhat. 29 30config DEBUG_PAGEALLOC 31 bool "Debug page memory allocations" 32 depends on DEBUG_KERNEL && !HIBERNATION 33 help 34 Unmap pages from the kernel linear mapping after free_pages(). 35 This results in a large slowdown, but helps to find certain types 36 of memory corruptions. 37 38 39config HCALL_STATS 40 bool "Hypervisor call instrumentation" 41 depends on PPC_PSERIES && DEBUG_FS 42 help 43 Adds code to keep track of the number of hypervisor calls made and 44 the amount of time spent in hypervisor calls. Wall time spent in 45 each call is always calculated, and if available CPU cycles spent 46 are also calculated. A directory named hcall_inst is added at the 47 root of the debugfs filesystem. Within the hcall_inst directory 48 are files that contain CPU specific call statistics. 49 50 This option will add a small amount of overhead to all hypervisor 51 calls. 52 53config CODE_PATCHING_SELFTEST 54 bool "Run self-tests of the code-patching code." 55 depends on DEBUG_KERNEL 56 default n 57 58config FTR_FIXUP_SELFTEST 59 bool "Run self-tests of the feature-fixup code." 60 depends on DEBUG_KERNEL 61 default n 62 63config MSI_BITMAP_SELFTEST 64 bool "Run self-tests of the MSI bitmap code." 65 depends on DEBUG_KERNEL 66 default n 67 68config XMON 69 bool "Include xmon kernel debugger" 70 depends on DEBUG_KERNEL 71 help 72 Include in-kernel hooks for the xmon kernel monitor/debugger. 73 Unless you are intending to debug the kernel, say N here. 74 Make sure to enable also CONFIG_BOOTX_TEXT on Macs. Otherwise 75 nothing will appear on the screen (xmon writes directly to the 76 framebuffer memory). 77 The cmdline option 'xmon' or 'xmon=early' will drop into xmon 78 very early during boot. 'xmon=on' will just enable the xmon 79 debugger hooks. 'xmon=off' will disable the debugger hooks 80 if CONFIG_XMON_DEFAULT is set. 81 xmon will print a backtrace on the very first invocation. 82 'xmon=nobt' will disable this autobacktrace. 83 84config XMON_DEFAULT 85 bool "Enable xmon by default" 86 depends on XMON 87 help 88 xmon is normally disabled unless booted with 'xmon=on'. 89 Use 'xmon=off' to disable xmon init during runtime. 90 91config XMON_DISASSEMBLY 92 bool "Include disassembly support in xmon" 93 depends on XMON 94 default y 95 help 96 Include support for disassembling in xmon. You probably want 97 to say Y here, unless you're building for a memory-constrained 98 system. 99 100config DEBUGGER 101 bool 102 depends on KGDB || XMON 103 default y 104 105config IRQSTACKS 106 bool "Use separate kernel stacks when processing interrupts" 107 help 108 If you say Y here the kernel will use separate kernel stacks 109 for handling hard and soft interrupts. This can help avoid 110 overflowing the process kernel stacks. 111 112config VIRQ_DEBUG 113 bool "Expose hardware/virtual IRQ mapping via debugfs" 114 depends on DEBUG_FS 115 help 116 This option will show the mapping relationship between hardware irq 117 numbers and virtual irq numbers. The mapping is exposed via debugfs 118 in the file powerpc/virq_mapping. 119 120 If you don't know what this means you don't need it. 121 122config BDI_SWITCH 123 bool "Include BDI-2000 user context switcher" 124 depends on DEBUG_KERNEL && PPC32 125 help 126 Include in-kernel support for the Abatron BDI2000 debugger. 127 Unless you are intending to debug the kernel with one of these 128 machines, say N here. 129 130config BOOTX_TEXT 131 bool "Support for early boot text console (BootX or OpenFirmware only)" 132 depends on PPC_OF && PPC_MULTIPLATFORM 133 help 134 Say Y here to see progress messages from the boot firmware in text 135 mode. Requires either BootX or Open Firmware. 136 137config PPC_EARLY_DEBUG 138 bool "Early debugging (dangerous)" 139 # PPC_EARLY_DEBUG on 440 leaves AS=1 mappings above the TLB high water 140 # mark, which doesn't work with current 440 KVM. 141 depends on !KVM 142 help 143 Say Y to enable some early debugging facilities that may be available 144 for your processor/board combination. Those facilities are hacks 145 intended to debug problems early during boot, this should not be 146 enabled in a production kernel. 147 Note that enabling this will also cause the kernel default log level 148 to be pushed to max automatically very early during boot 149 150choice 151 prompt "Early debugging console" 152 depends on PPC_EARLY_DEBUG 153 help 154 Use the selected console for early debugging. Careful, if you 155 enable debugging for the wrong type of machine your kernel 156 _will not boot_. 157 158config PPC_EARLY_DEBUG_LPAR 159 bool "LPAR HV Console" 160 depends on PPC_PSERIES 161 help 162 Select this to enable early debugging for a machine with a HVC 163 console on vterm 0. 164 165config PPC_EARLY_DEBUG_G5 166 bool "Apple G5" 167 depends on PPC_PMAC64 168 help 169 Select this to enable early debugging for Apple G5 machines. 170 171config PPC_EARLY_DEBUG_RTAS_PANEL 172 bool "RTAS Panel" 173 depends on PPC_RTAS 174 help 175 Select this to enable early debugging via the RTAS panel. 176 177config PPC_EARLY_DEBUG_RTAS_CONSOLE 178 bool "RTAS Console" 179 depends on PPC_RTAS 180 select UDBG_RTAS_CONSOLE 181 help 182 Select this to enable early debugging via the RTAS console. 183 184config PPC_EARLY_DEBUG_MAPLE 185 bool "Maple real mode" 186 depends on PPC_MAPLE 187 help 188 Select this to enable early debugging for Maple. 189 190config PPC_EARLY_DEBUG_ISERIES 191 bool "iSeries HV Console" 192 depends on PPC_ISERIES 193 help 194 Select this to enable early debugging for legacy iSeries. You need 195 to hit "Ctrl-x Ctrl-x" to see the messages on the console. 196 197config PPC_EARLY_DEBUG_PAS_REALMODE 198 bool "PA Semi real mode" 199 depends on PPC_PASEMI 200 help 201 Select this to enable early debugging for PA Semi. 202 Output will be on UART0. 203 204config PPC_EARLY_DEBUG_BEAT 205 bool "Beat HV Console" 206 depends on PPC_CELLEB 207 select PPC_UDBG_BEAT 208 help 209 Select this to enable early debugging for Celleb with Beat. 210 211config PPC_EARLY_DEBUG_44x 212 bool "Early serial debugging for IBM/AMCC 44x CPUs" 213 depends on 44x 214 help 215 Select this to enable early debugging for IBM 44x chips via the 216 inbuilt serial port. If you enable this, ensure you set 217 PPC_EARLY_DEBUG_44x_PHYSLOW below to suit your target board. 218 219config PPC_EARLY_DEBUG_40x 220 bool "Early serial debugging for IBM/AMCC 40x CPUs" 221 depends on 40x 222 help 223 Select this to enable early debugging for IBM 40x chips via the 224 inbuilt serial port. This works on chips with a 16550 compatible 225 UART. Xilinx chips with uartlite cannot use this option. 226 227config PPC_EARLY_DEBUG_CPM 228 bool "Early serial debugging for Freescale CPM-based serial ports" 229 depends on SERIAL_CPM 230 select PIN_TLB if PPC_8xx 231 help 232 Select this to enable early debugging for Freescale chips 233 using a CPM-based serial port. This assumes that the bootwrapper 234 has run, and set up the CPM in a particular way. 235 236endchoice 237 238config PPC_EARLY_DEBUG_44x_PHYSLOW 239 hex "Low 32 bits of early debug UART physical address" 240 depends on PPC_EARLY_DEBUG_44x 241 default "0x40000200" 242 help 243 You probably want 0x40000200 for ebony boards and 244 0x40000300 for taishan 245 246config PPC_EARLY_DEBUG_44x_PHYSHIGH 247 hex "EPRN of early debug UART physical address" 248 depends on PPC_EARLY_DEBUG_44x 249 default "0x1" 250 251config PPC_EARLY_DEBUG_40x_PHYSADDR 252 hex "Early debug UART physical address" 253 depends on PPC_EARLY_DEBUG_40x 254 default "0xef600300" 255 256config PPC_EARLY_DEBUG_CPM_ADDR 257 hex "CPM UART early debug transmit descriptor address" 258 depends on PPC_EARLY_DEBUG_CPM 259 default "0xfa202008" if PPC_EP88XC 260 default "0xf0001ff8" if CPM2 261 default "0xff002008" if CPM1 262 help 263 This specifies the address of the transmit descriptor 264 used for early debug output. Because it is needed before 265 platform probing is done, all platforms selected must 266 share the same address. 267 268endmenu 269