menu "Kernel hacking" config TRACE_IRQFLAGS_SUPPORT bool default y source "lib/Kconfig.debug" config EARLY_PRINTK bool "Early printk" if EMBEDDED && DEBUG_KERNEL default y help Write kernel log output directly into the VGA buffer or to a serial port. This is useful for kernel debugging when your machine crashes very early before the console code is initialized. For normal operation it is not recommended because it looks ugly and doesn't cooperate with klogd/syslogd or the X server. You should normally N here, unless you want to debug such a crash. config DEBUG_STACKOVERFLOW bool "Check for stack overflows" depends on DEBUG_KERNEL help This option will cause messages to be printed if free stack space drops below a certain limit. config DEBUG_STACK_USAGE bool "Stack utilization instrumentation" depends on DEBUG_KERNEL help Enables the display of the minimum amount of free stack which each task has ever had available in the sysrq-T and sysrq-P debug output. This option will slow down process creation somewhat. comment "Page alloc debug is incompatible with Software Suspend on i386" depends on DEBUG_KERNEL && SOFTWARE_SUSPEND config DEBUG_PAGEALLOC bool "Debug page memory allocations" depends on DEBUG_KERNEL && !SOFTWARE_SUSPEND && !HUGETLBFS help Unmap pages from the kernel linear mapping after free_pages(). This results in a large slowdown, but helps to find certain types of memory corruptions. config DEBUG_RODATA bool "Write protect kernel read-only data structures" depends on DEBUG_KERNEL help Mark the kernel read-only data as write-protected in the pagetables, in order to catch accidental (and incorrect) writes to such const data. This option may have a slight performance impact because a portion of the kernel code won't be covered by a 2MB TLB anymore. If in doubt, say "N". config 4KSTACKS bool "Use 4Kb for kernel stacks instead of 8Kb" depends on DEBUG_KERNEL help If you say Y here the kernel will use a 4Kb stacksize for the kernel stack attached to each process/thread. This facilitates running more threads on a system and also reduces the pressure on the VM subsystem for higher order allocations. This option will also use IRQ stacks to compensate for the reduced stackspace. config X86_FIND_SMP_CONFIG bool depends on X86_LOCAL_APIC || X86_VOYAGER default y config X86_MPPARSE bool depends on X86_LOCAL_APIC && !X86_VISWS default y config DOUBLEFAULT default y bool "Enable doublefault exception handler" if EMBEDDED help This option allows trapping of rare doublefault exceptions that would otherwise cause a system to silently reboot. Disabling this option saves about 4k and might cause you much additional grey hair. endmenu