menu "Kernel hacking"
-source "lib/Kconfig.debug"
-
-config CRASH_DUMP
- tristate "Crash dump support (EXPERIMENTAL)"
- depends on EXPERIMENTAL
- default n
- ---help---
- Say Y here to enable saving an image of system memory when a panic
- or other error occurs. Dumps can also be forced with the SysRq+d
- key if MAGIC_SYSRQ is enabled.
-
-config CRASH_DUMP_BLOCKDEV
- tristate "Crash dump block device driver"
- depends on CRASH_DUMP
- help
- Say Y to allow saving crash dumps directly to a disk device.
-
-config CRASH_DUMP_NETDEV
- tristate "Crash dump network device driver"
- depends on CRASH_DUMP
- help
- Say Y to allow saving crash dumps over a network device.
-
-config CRASH_DUMP_MEMDEV
- bool "Crash dump staged memory driver"
- depends on CRASH_DUMP
- help
- Say Y to allow intermediate saving crash dumps in spare
- memory pages which would then be written out to disk
- later.
-
-config CRASH_DUMP_SOFTBOOT
- bool "Save crash dump across a soft reboot"
- depends on CRASH_DUMP_MEMDEV
- help
- Say Y to allow a crash dump to be preserved in memory
- pages across a soft reboot and written out to disk
- thereafter. For this to work, CRASH_DUMP must be
- configured as part of the kernel (not as a module).
-
-config CRASH_DUMP_COMPRESS_RLE
- tristate "Crash dump RLE compression"
- depends on CRASH_DUMP
- help
- Say Y to allow saving dumps with Run Length Encoding compression.
-
-config CRASH_DUMP_COMPRESS_GZIP
- tristate "Crash dump GZIP compression"
- select ZLIB_INFLATE
- select ZLIB_DEFLATE
- depends on CRASH_DUMP
- help
- Say Y to allow saving dumps with Gnu Zip compression.
-
-config X86_FIND_SMP_CONFIG
+config TRACE_IRQFLAGS_SUPPORT
bool
- depends on X86_LOCAL_APIC || X86_VOYAGER
default y
-config X86_MPPARSE
- bool
- depends on X86_LOCAL_APIC && !X86_VISWS
- default y
+source "lib/Kconfig.debug"
config EARLY_PRINTK
- bool "Early printk" if EMBEDDED
+ bool "Early printk" if EMBEDDED && DEBUG_KERNEL
default y
help
Write kernel log output directly into the VGA buffer or to a serial
with klogd/syslogd or the X server. You should normally N here,
unless you want to debug such a crash.
-config KPROBES
- bool "Kprobes"
- depends on DEBUG_KERNEL
- help
- Kprobes allows you to trap at almost any kernel address and
- execute a callback function. register_kprobe() establishes
- a probepoint and specifies the callback. Kprobes is useful
- for kernel debugging, non-intrusive instrumentation and testing.
- If in doubt, say "N".
-
-config DEBUG_PAGEALLOC
- bool "Page alloc debugging"
- depends on DEBUG_KERNEL
- 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_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"
This option will slow down process creation somewhat.
-config IRQSTACKS
- bool "Use separate IRQ stacks"
- help
- This option subsumes the IRQ stack implementation of the orig. 4KSTACK
- support. You must use this if you select 4KB stacks!
-
-config STACK_SIZE_SHIFT
- int "Kernel stack size (12 => 4KB, 13 => 8KB, 14 => 16KB)"
- range 12 14
- default 12 if IRQSTACKS
- default 13
- help
- Select kernel stack size. 4KB stacks are best as they let
- the system scale further. Use 8KB stacks if you have an
- experimental kernel where a stack overlow with a 4KB stack
- might occur. Use 16KB stacks if you want to safely support
- Windows device drivers using either Linuxant or ndiswrapper.
-
-config STACK_WARN
- int "Print stack trace when stack grows beyond specified bytes"
- default 4096 if IRQSTACKS
- default 4096
- help
- The kernel will print a stack trace when the current stack exceeds
- the specified size.
-
-config X86_STACK_CHECK
- bool "Aggressively check for stack overflows"
- default n
- help
- Say Y here to have the kernel attempt to detect when the per-task
- kernel stack overflows.
-
- Some older versions of gcc don't handle the -p option correctly.
- Kernprof is affected by the same problem, which is described here:
- http://oss.sgi.com/projects/kernprof/faq.html#Q9
-
- Basically, if you get oopses in __free_pages_ok during boot when
- you have this turned on, you need to fix gcc. The Redhat 2.96
- version and gcc-3.x seem to work.
-
- If not debugging a stack overflow problem, say N
-
-config STACK_PANIC
- int "Panic when stack approaches with specified bytes of the stack limit"
- depends on X86_STACK_CHECK
- default 512 if IRQSTACKS
- default 512
- help
- Panic if the stack grows to within specified byte range.
+comment "Page alloc debug is incompatible with Software Suspend on i386"
+ depends on DEBUG_KERNEL && SOFTWARE_SUSPEND
config DEBUG_PAGEALLOC
- bool "Page alloc debugging"
- depends on DEBUG_KERNEL
+ 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 SCHEDSTATS
- bool "Collect scheduler statistics"
- depends on DEBUG_KERNEL && PROC_FS
+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, additional code will be inserted into the
- scheduler and related routines to collect statistics about
- scheduler behavior and provide them in /proc/schedstat. These
- stats may be useful for both tuning and debugging the scheduler
- If you aren't debugging the scheduler or trying to tune a specific
- application, you can say N to avoid the very slight overhead
- this adds.
+ 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_VISWS
default y
+config DOUBLEFAULT
+ default y
+ bool "Enable doublefault exception handler" if EMBEDDED
+ depends on !X86_NO_TSS
+ 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.
+
+config DEBUG_PARAVIRT
+ bool "Enable some paravirtualization debugging"
+ default y
+ depends on PARAVIRT && DEBUG_KERNEL
+ help
+ Currently deliberately clobbers regs which are allowed to be
+ clobbered in inlined paravirt hooks, even in native mode.
+ If turning this off solves a problem, then DISABLE_INTERRUPTS() or
+ ENABLE_INTERRUPTS() is lying about what registers can be clobbered.
+
endmenu
git://git.onelab.eu / linux-2.6.git / blobdiff