3 source "lib/Kconfig.debug"
6 bool "Early printk" if EMBEDDED
9 Write kernel log output directly into the VGA buffer or to a serial
12 This is useful for kernel debugging when your machine crashes very
13 early before the console code is initialized. For normal operation
14 it is not recommended because it looks ugly and doesn't cooperate
15 with klogd/syslogd or the X server. You should normally N here,
16 unless you want to debug such a crash.
20 depends on DEBUG_KERNEL
22 Kprobes allows you to trap at almost any kernel address and
23 execute a callback function. register_kprobe() establishes
24 a probepoint and specifies the callback. Kprobes is useful
25 for kernel debugging, non-intrusive instrumentation and testing.
28 config DEBUG_PAGEALLOC
29 bool "Page alloc debugging"
30 depends on DEBUG_KERNEL
32 Unmap pages from the kernel linear mapping after free_pages().
33 This results in a large slowdown, but helps to find certain types
34 of memory corruptions.
36 config DEBUG_STACKOVERFLOW
37 bool "Check for stack overflows"
38 depends on DEBUG_KERNEL
40 config DEBUG_STACK_USAGE
41 bool "Stack utilization instrumentation"
42 depends on DEBUG_KERNEL
44 Enables the display of the minimum amount of free stack which each
45 task has ever had available in the sysrq-T and sysrq-P debug output.
47 This option will slow down process creation somewhat.
50 bool "Use separate IRQ stacks"
52 This option subsumes the IRQ stack implementation of the orig. 4KSTACK
53 support. You must use this if you select 4KB stacks!
55 config STACK_SIZE_SHIFT
56 int "Kernel stack size (12 => 4KB, 13 => 8KB, 14 => 16KB)"
58 default 12 if IRQSTACKS
61 Select kernel stack size. 4KB stacks are best as they let
62 the system scale further. Use 8KB stacks if you have an
63 experimental kernel where a stack overlow with a 4KB stack
64 might occur. Use 16KB stacks if you want to safely support
65 Windows device drivers using either Linuxant or ndiswrapper.
68 int "Print stack trace when stack grows beyond specified bytes"
69 default 4096 if IRQSTACKS
72 The kernel will print a stack trace when the current stack exceeds
75 config X86_STACK_CHECK
76 bool "Aggressively check for stack overflows"
79 Say Y here to have the kernel attempt to detect when the per-task
80 kernel stack overflows.
82 Some older versions of gcc don't handle the -p option correctly.
83 Kernprof is affected by the same problem, which is described here:
84 http://oss.sgi.com/projects/kernprof/faq.html#Q9
86 Basically, if you get oopses in __free_pages_ok during boot when
87 you have this turned on, you need to fix gcc. The Redhat 2.96
88 version and gcc-3.x seem to work.
90 If not debugging a stack overflow problem, say N
93 int "Panic when stack approaches with specified bytes of the stack limit"
94 depends on X86_STACK_CHECK
95 default 512 if IRQSTACKS
98 Panic if the stack grows to within specified byte range.
100 config DEBUG_PAGEALLOC
101 bool "Page alloc debugging"
102 depends on DEBUG_KERNEL
104 Unmap pages from the kernel linear mapping after free_pages().
105 This results in a large slowdown, but helps to find certain types
106 of memory corruptions.
108 config X86_FIND_SMP_CONFIG
110 depends on X86_LOCAL_APIC || X86_VOYAGER
115 depends on X86_LOCAL_APIC && !X86_VISWS