diff options
| author | Josh Poimboeuf <jpoimboe@redhat.com> | 2017-07-25 08:54:24 -0500 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-07-26 14:05:36 +0200 |
| commit | 81d387190039c14edac8de2b3ec789beb899afd9 (patch) | |
| tree | 73d1c44e4b1b212457e9cea254ee7d69ccc4ba75 /arch/x86/Kconfig.debug | |
| parent | a34a766ff96d9e88572e35a45066279e40a85d84 (diff) | |
x86/kconfig: Consolidate unwinders into multiple choice selection
There are three mutually exclusive unwinders. Make that more obvious by
combining them into a multiple-choice selection:
CONFIG_FRAME_POINTER_UNWINDER
CONFIG_ORC_UNWINDER
CONFIG_GUESS_UNWINDER (if CONFIG_EXPERT=y)
Frame pointers are still the default (for now).
The old CONFIG_FRAME_POINTER option is still used in some
arch-independent places, so keep it around, but make it
invisible to the user on x86 - it's now selected by
CONFIG_FRAME_POINTER_UNWINDER=y.
Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/20170725135424.zukjmgpz3plf5pmt@treble
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/Kconfig.debug')
| -rw-r--r-- | arch/x86/Kconfig.debug | 47 |
1 files changed, 40 insertions, 7 deletions
diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug index 268a318f9439..93bbb31456fd 100644 --- a/arch/x86/Kconfig.debug +++ b/arch/x86/Kconfig.debug @@ -355,9 +355,32 @@ config PUNIT_ATOM_DEBUG The current power state can be read from /sys/kernel/debug/punit_atom/dev_power_state +choice + prompt "Choose kernel unwinder" + default FRAME_POINTER_UNWINDER + ---help--- + This determines which method will be used for unwinding kernel stack + traces for panics, oopses, bugs, warnings, perf, /proc/<pid>/stack, + livepatch, lockdep, and more. + +config FRAME_POINTER_UNWINDER + bool "Frame pointer unwinder" + select FRAME_POINTER + ---help--- + This option enables the frame pointer unwinder for unwinding kernel + stack traces. + + The unwinder itself is fast and it uses less RAM than the ORC + unwinder, but the kernel text size will grow by ~3% and the kernel's + overall performance will degrade by roughly 5-10%. + + This option is recommended if you want to use the livepatch + consistency model, as this is currently the only way to get a + reliable stack trace (CONFIG_HAVE_RELIABLE_STACKTRACE). + config ORC_UNWINDER bool "ORC unwinder" - depends on X86_64 && !FRAME_POINTER + depends on X86_64 select STACK_VALIDATION ---help--- This option enables the ORC (Oops Rewind Capability) unwinder for @@ -371,12 +394,22 @@ config ORC_UNWINDER Enabling this option will increase the kernel's runtime memory usage by roughly 2-4MB, depending on your kernel config. -config FRAME_POINTER_UNWINDER - def_bool y - depends on !ORC_UNWINDER && FRAME_POINTER - config GUESS_UNWINDER - def_bool y - depends on !ORC_UNWINDER && !FRAME_POINTER + bool "Guess unwinder" + depends on EXPERT + ---help--- + This option enables the "guess" unwinder for unwinding kernel stack + traces. It scans the stack and reports every kernel text address it + finds. Some of the addresses it reports may be incorrect. + + While this option often produces false positives, it can still be + useful in many cases. Unlike the other unwinders, it has no runtime + overhead. + +endchoice + +config FRAME_POINTER + depends on !ORC_UNWINDER && !GUESS_UNWINDER + bool endmenu |