Enable compiling with gcc tracing
PATCH 1/1 Enable compiling with gcc tracing
Make minimal adjustments in order to enable the compilation of the xen source-code with gcc-6's -fsanitize-coverage=trace-pc option.
Due to a bug in Xen's build-system the flag for the compiler has to be handed in via the command line, i.e. for compiling one would use:
make CC=<path to gcc-6>
This is an experimental patch as in a final version you would not want all files to be compiled with this option by default.
--- xen/Rules.mk | 1 + xen/common/kernel.c | 2 ++ xen/include/xen/hypercall.h | 2 ++ 3 files changed, 5 insertions(+)
xen/Rules.mk +1 -0
@@ -46,6 +46,7 @@ else CFLAGS += -O2 -fomit-frame-pointer endif +CFLAGS += -fsanitize-coverage=trace-pc CFLAGS += -nostdinc -fno-builtin -fno-common CFLAGS += -Werror -Wredundant-decls -Wno-pointer-arith CFLAGS += -pipe -g -D__XEN__ -include $(BASEDIR)/include/xen/config.h
xen/common/kernel.c +2 -0
@@ -238,6 +238,8 @@ void __init do_initcalls(void)# define DO (fn) long do_##fn +void __sanitizer_cov_trace_pc (void ) {return ; } +#endif /*
xen/include/xen/hypercall.h +2 -0
@@ -19,6 +19,8 @@#include <asm/hypercall.h> #include <xsm/xsm.h> +extern void __sanitizer_cov_trace_pc (void ); + extern long do_sched_op( int cmd,
Signature · 7 lines
2.11.0 _______________________________________________ Xen-devel mailing list [email protected] https://lists.xen.org/xen-devel
Quoted 7 lines · Felix Schmoll
Make minimal adjustments in order to enable the compilation of the xen source-code with gcc-6's -fsanitize-coverage=trace-pc option.
Due to a bug in Xen's build-system the flag for the compiler has to be handed in via the command line, i.e. for compiling one would use:
Quoted 6 lines
make CC=<path to gcc-6>
This is an experimental patch as in a final version you would not want all files to be compiled with this option by default.
Signed-off-by Felix Schmoll <[email protected]>
Have you tried booting Xen with this patch applied and trace-pc enabled?
Quoted 23 lines
--- xen/Rules.mk | 1 + xen/common/kernel.c | 2 ++ xen/include/xen/hypercall.h | 2 ++ 3 files changed, 5 insertions(+)xen/Rules.mk +1
-0@@ -46,6 +46,7 @@ else CFLAGS += -O2 -fomit-frame-pointer endif +CFLAGS += -fsanitize-coverage=trace-pc CFLAGS += -nostdinc -fno-builtin -fno-common CFLAGS += -Werror -Wredundant-decls -Wno-pointer-arith CFLAGS += -pipe -g -D__XEN__ -include $(BASEDIR)/include/xen/config.hxen/common/kernel.c +0
-0
xen/common/kernel.c void __init do_initcalls(void) · line 242
Quoted 5 lines
xen/common/kernel.c +2
-0@@ -238,6 +238,8 @@ void __init do_initcalls(void)# define DO (fn) long do_##fn +void __sanitizer_cov_trace_pc (void ) {return ; } +
IIRC this is going to recurse until stack overflows, right?
What I actually want you to do is to add a new file and hook it up in the build system.
And maybe if you feel like it, start looking at actually putting something inside the trace_pc function.
Hint, you can get hold of PC with __builtin_return_address(0).
Quoted 19 lines
xen/common/kernel.c +0
-0#endif /* xen/include/xen/hypercall.h +2
-0@@ -19,6 +19,8 @@#include <asm/hypercall.h> #include <xsm/xsm.h> +extern void __sanitizer_cov_trace_pc (void ); + extern long do_sched_op( int cmd,Signature · 1 line
2.11.0
_______________________________________________
Xen-devel mailing list
[email protected]
https://lists.xen.org/xen-devel
PATCH 1/1 Enable compiling with gcc tracing
In reply to Felix SchmollMake minimal adjustments in order to enable the compilation of the xen source-code with gcc-6's -fsanitize-coverage=trace-pc option.
Due to a bug in Xen's build-system the flag for the compiler has to be handed in via the command line, i.e. for compiling one would use:
make CC=<path to gcc-6>
This is an experimental patch as in a final version you would not want all files to be compiled with this option by default.
--- xen/Rules.mk | 9 ++++++++- xen/include/xen/hypercall.h | 1 + xen/include/xen/my_tracer.h | 6 ++++++ xen/my_tracer.c | 1 + 4 files changed, 16 insertions(+), 1 deletion(-) create mode 100644 xen/include/xen/my_tracer.h create mode 100644 xen/my_tracer.c
xen/Rules.mk +8 -1
@@ -33,7 +33,9 @@ override TARGET_ARCH := $(shell echo $(XEN_TARGET_ARCH) | \ TARGET := $(BASEDIR)/xen + # Note that link order matters! +ALL_OBJS-y += $(BASEDIR)/my_tracer.o ALL_OBJS-y += $(BASEDIR)/common/built_in.o ALL_OBJS-y += $(BASEDIR)/drivers/built_in.o ALL_OBJS-y += $(BASEDIR)/xsm/built_in.o
@@ -46,6 +48,7 @@ else CFLAGS += -O2 -fomit-frame-pointer endif +CFLAGS += -fsanitize-coverage=trace-pc CFLAGS += -nostdinc -fno-builtin -fno-common CFLAGS += -Werror -Wredundant-decls -Wno-pointer-arith CFLAGS += -pipe -g -D__XEN__ -include $(BASEDIR)/include/xen/config.h
@@ -171,7 +174,11 @@ _clean_%/: FORCE $(MAKE) -f $(BASEDIR)/Rules.mk -C $* clean %.o: %.c Makefile - $(CC) $(CFLAGS) -c $< -o $@ + if [ $@ != $(BASEDIR)/my_tracer.o ]; \ + then $(CC) $(CFLAGS) -c $< -o $@; \ + else \ + $(CC) -include $(BASEDIR)/include/xen/my_tracer.h -c $(BASEDIR)/my_tracer.c -o $(BASEDIR)/my_tracer.o; \ + fi %.o: %.S Makefile $(CC) $(AFLAGS) -c $< -o $@
xen/include/xen/hypercall.h +1 -0
@@ -5,6 +5,7 @@#ifndef __XEN_HYPERCALL_H__#define __XEN_HYPERCALL_H__ +#include <xen/my_tracer.h> #include <xen/types.h> #include <xen/time.h> #include <public/xen.h>
xen/include/xen/my_tracer.h new file +6 -0
@@ -0,0 +1,6 @@ +#ifndef _TRACE_H_ +#define _TRACE_H_ + +void __sanitizer_cov_trace_pc (void ); + +#endif
xen/my_tracer.c new file +1 -0
@@ -0,0 +1 @@ +void __sanitizer_cov_trace_pc (void ) {return ; }
Signature · 7 lines
2.11.0 _______________________________________________ Xen-devel mailing list [email protected] https://lists.xen.org/xen-devel
Cool. I think Xen should boot with this.
You've successfully finished what I asked for. Now you can divert your energy to polish your application. :-)
Quoted 9 lines · Felix Schmoll
Make minimal adjustments in order to enable the compilation of the xen source-code with gcc-6's -fsanitize-coverage=trace-pc option.
Due to a bug in Xen's build-system the flag for the compiler has to be handed in via the command line, i.e. for compiling one would use:
make CC=<path to gcc-6>
OOI, how can I reproduce the bug you met?
If you mean it doesn't work with:
CC=XXX make
it is expected.
Wei.
_______________________________________________
Xen-devel mailing list
[email protected]
https://lists.xen.org/xen-devel
2017-03-30 17:46 GMT+02:00 Wei Liu <[email protected]>:
Quoted 16 lines
Cool. I think Xen should boot with this.
You've successfully finished what I asked for. Now you can divert your energy to polish your application. :-)
Quoted 9 lines · Felix Schmoll
Make minimal adjustments in order to enable the compilation of the xen source-code with gcc-6's -fsanitize-coverage=trace-pc option.
Due to a bug in Xen's build-system the flag for the compiler has to be handed in via the command line, i.e. for compiling one would use:
make CC=<path to gcc-6>
Quoted 8 lines
OOI, how can I reproduce the bug you met?
If you mean it doesn't work with:
CC=XXX make
it is expected.
Yeah, this is what I meant.
I recalled having read on some archived mailing list that it was a bug, but whatever.
Felix
Quoted 3 lines
Wei.
_______________________________________________
Xen-devel mailing list
[email protected]
https://lists.xen.org/xen-devel