From a34a766ff96d9e88572e35a45066279e40a85d84 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 24 Jul 2017 18:36:58 -0500 Subject: x86/kconfig: Make it easier to switch to the new ORC unwinder A couple of Kconfig changes which make it much easier to switch to the new CONFIG_ORC_UNWINDER: 1) Remove x86 dependencies on CONFIG_FRAME_POINTER for lockdep, latencytop, and fault injection. x86 has a 'guess' unwinder which just scans the stack for kernel text addresses. It's not 100% accurate but in many cases it's good enough. This allows those users who don't want the text overhead of the frame pointer or ORC unwinders to still use these features. More importantly, this also makes it much more straightforward to disable frame pointers. 2) Make CONFIG_ORC_UNWINDER depend on !CONFIG_FRAME_POINTER. While it would be possible to have both enabled, it doesn't really make sense to do so. So enforce a sane configuration to prevent the user from making a dumb mistake. With these changes, when you disable CONFIG_FRAME_POINTER, "make oldconfig" will ask if you want to enable CONFIG_ORC_UNWINDER. Signed-off-by: Josh Poimboeuf Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/9985fb91ce5005fe33ea5cc2a20f14bd33c61d03.1500938583.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- lib/Kconfig.debug | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'lib/Kconfig.debug') diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 0f0d019ffb99..32a48e739e26 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1124,7 +1124,7 @@ config LOCKDEP bool depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT select STACKTRACE - select FRAME_POINTER if !MIPS && !PPC && !ARM_UNWIND && !S390 && !MICROBLAZE && !ARC && !SCORE + select FRAME_POINTER if !MIPS && !PPC && !ARM_UNWIND && !S390 && !MICROBLAZE && !ARC && !SCORE && !X86 select KALLSYMS select KALLSYMS_ALL @@ -1543,7 +1543,7 @@ config FAULT_INJECTION_STACKTRACE_FILTER depends on FAULT_INJECTION_DEBUG_FS && STACKTRACE_SUPPORT depends on !X86_64 select STACKTRACE - select FRAME_POINTER if !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM_UNWIND && !ARC && !SCORE + select FRAME_POINTER if !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM_UNWIND && !ARC && !SCORE && !X86 help Provide stacktrace filter for fault-injection capabilities @@ -1552,7 +1552,7 @@ config LATENCYTOP depends on DEBUG_KERNEL depends on STACKTRACE_SUPPORT depends on PROC_FS - select FRAME_POINTER if !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM_UNWIND && !ARC + select FRAME_POINTER if !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM_UNWIND && !ARC && !X86 select KALLSYMS select KALLSYMS_ALL select STACKTRACE -- cgit v1.2.3-59-g8ed1b