x86/stacktrace: Enable HAVE_RELIABLE_STACKTRACE for the ORC unwinder

In SUSE, we need a reliable stack unwinder for kernel live patching, but
we do not want to enable frame pointers for performance reasons. So
after the previous patches to make the ORC reliable, mark ORC as a
reliable stack unwinder on x86.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/lkml/20180518064713.26440-6-jslaby@suse.cz
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index f1dbb4e..c4d64b1 100644 (file)
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -180,7 +180,7 @@ config X86
        select HAVE_PERF_USER_STACK_DUMP
        select HAVE_RCU_TABLE_FREE
        select HAVE_REGS_AND_STACK_ACCESS_API
-       select HAVE_RELIABLE_STACKTRACE         if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION
+       select HAVE_RELIABLE_STACKTRACE         if X86_64 && (UNWINDER_FRAME_POINTER || UNWINDER_ORC) && STACK_VALIDATION
        select HAVE_STACKPROTECTOR              if CC_HAS_SANE_STACKPROTECTOR
        select HAVE_STACK_VALIDATION            if X86_64
        select HAVE_RSEQ