So on top of you entry-v8-full; I had to chase one of those
instrumentation_end() escapes an (extended) basic block chase (again!).
How about we do something like the below; that fixes the current case
(rcu_eqs_enter) but also kills the entire class.
---
arch/x86/include/asm/bug.h | 2 +-
include/linux/compiler.h | 16 +++++++++++++---
include/linux/compiler_types.h | 4 ----
3 files changed, 14 insertions(+), 8 deletions(-)
diff --git a/arch/x86/include/asm/bug.h b/arch/x86/include/asm/bug.h
index f128e5c2ed42..fb34ff641e0a 100644
--- a/arch/x86/include/asm/bug.h
+++ b/arch/x86/include/asm/bug.h
@@ -79,8 +79,8 @@ do {
\
do { \
instrumentation_begin(); \
_BUG_FLAGS(ASM_UD2, BUGFLAG_WARNING|(flags)); \
- instrumentation_end(); \
annotate_reachable(); \
+ instrumentation_end(); \
} while (0)
#include <asm-generic/bug.h>
diff --git a/include/linux/compiler.h b/include/linux/compiler.h
index 7db5902f8f6e..b4c248e6b76a 100644
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -120,25 +120,35 @@ void ftrace_likely_update(struct ftrace_likely_data *f,
int val,
/* Annotate a C jump table to allow objtool to follow the code flow */
#define __annotate_jump_table __section(.rodata..c_jump_table)
+#ifdef CONFIG_DEBUG_ENTRY
+/* Section for code which can't be instrumented at all */
+#define noinstr
\
+ noinline notrace __attribute((__section__(".noinstr.text")))
+
/* Begin/end of an instrumentation safe region */
-#define instrumentation_begin() ({
\
+#define instrumentation_begin() ({ \
asm volatile("%c0:\n\t" \
".pushsection .discard.instr_begin\n\t" \
".long %c0b - .\n\t" \
".popsection\n\t" : : "i" (__COUNTER__)); \
})
-#define instrumentation_end() ({
\
- asm volatile("%c0:\n\t" \
+#define instrumentation_end() ({ \
+ asm volatile("%c0: nop\n\t" \
".pushsection .discard.instr_end\n\t" \
".long %c0b - .\n\t" \
".popsection\n\t" : : "i" (__COUNTER__)); \
})
+#endif /* CONFIG_DEBUG_ENTRY */
#else
#define annotate_reachable()
#define annotate_unreachable()
#define __annotate_jump_table
+#endif
+
+#ifndef noinstr
+#define noinstr noinline notrace
#define instrumentation_begin() do { } while(0)
#define instrumentation_end() do { } while(0)
#endif
diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h
index ea15ea99efb4..6ed0612bc143 100644
--- a/include/linux/compiler_types.h
+++ b/include/linux/compiler_types.h
@@ -118,10 +118,6 @@ struct ftrace_likely_data {
#define notrace
__attribute__((__no_instrument_function__))
#endif
-/* Section for code which can't be instrumented at all */
-#define noinstr
\
- noinline notrace __attribute((__section__(".noinstr.text")))
-
/*
* it doesn't make sense on ARM (currently the only user of __naked)
* to trace naked functions because then mcount is called without
