On contrary to previously existing scheme, the *.dbg image is a fully
functional binary now. A user still can run qemu/xen with a stripped
image, and attach gdb to it, specifying the *.dbg image as a source.
A full dbg images are not making more overhead comparing to
'--only-keep-debug' ones (apart from disk space), but are bringing
convenience.
Another effect of this patch - *.dbg file is produced
always (menuconfig is gone). The 'strip' operation does not cost us
much, and the stripped image equivalents to image build without debug
symbols. But even in production systems it is handy to have an image
with debug symbols by your side to perform a post-mortem analysis of a
crash.
This approach allows to have strip-able sections, existing only in the
*.dbg files. Now user can append the variable `STRIP_SECTIONS_FLAGS-y`
in the library/application makefile, to list all the section he does
not need in the final image.
Signed-off-by: Yuri Volchkov <yuri.volchkov@xxxxxxxxx>
---
Config.uk | 20 --------
Makefile.uk | 6 ---
plat/kvm/Linker.uk | 25 ++++------
plat/linuxu/Linker.uk | 20 ++++----
plat/xen/Linker.uk | 40 ++++++++--------
support/scripts/sect-strip.py | 87 +++++++++++++++++++++++++++++++++++
6 files changed, 124 insertions(+), 74 deletions(-)
create mode 100755 support/scripts/sect-strip.py
diff --git a/Config.uk b/Config.uk
index d0bfa823..bb791fdb 100644
--- a/Config.uk
+++ b/Config.uk
@@ -86,13 +86,6 @@ config OPTIMIZE_LTO
will increase overall building time but creates more efficient
Unikraft binaries.
-config DEBUG_SYMBOLS
- bool "Debugging information"
- default n
- help
- Build with debugging information.
-
-if DEBUG_SYMBOLS
choice
prompt "Debug information level"
default DEBUG_SYMBOLS_LVL3
@@ -121,24 +114,11 @@ config DEBUG_SYMBOLS_LVL3
support macro expansion.
endchoice
-config OPTIMIZE_DBGFILE
- bool "Create a debugging information file"
- default y
- help
- Create a separate file with debugging information
-
config OPTIMIZE_SYMFILE
bool "Create a symbols file"
default n
help
Create a separate file with all symbol locations
-endif
-
-config OPTIMIZE_STRIP
- bool "Strip final image"
- default y
- help
- Strip any extra information from image
config RECORD_BUILDTIME
bool "Keep track of Building time"
diff --git a/Makefile.uk b/Makefile.uk
index c6cf2306..3716fa64 100644
--- a/Makefile.uk
+++ b/Makefile.uk
@@ -40,18 +40,12 @@ CXXFLAGS-$(CONFIG_OPTIMIZE_LTO) += -flto
LIBLDFLAGS-$(CONFIG_OPTIMIZE_LTO) += $(CFLAGS) $(CFLAGS-y)
LDFLAGS-$(CONFIG_OPTIMIZE_LTO) += $(CFLAGS) $(CFLAGS-y)
-ifneq ($(CONFIG_DEBUG_SYMBOLS),y)
-CFLAGS += -g0
-CXXFLAGS += -g0
-LDFLAGS-y += -Wl,--strip-debug
-else
CFLAGS-$(CONFIG_DEBUG_SYMBOLS_LVL1) += -g1
CXXFLAGS-$(CONFIG_DEBUG_SYMBOLS_LVL1) += -g1
CFLAGS-$(CONFIG_DEBUG_SYMBOLS_LVL2) += -g2
CXXFLAGS-$(CONFIG_DEBUG_SYMBOLS_LVL2) += -g2
CFLAGS-$(CONFIG_DEBUG_SYMBOLS_LVL3) += -g3
CXXFLAGS-$(CONFIG_DEBUG_SYMBOLS_LVL3) += -g3
-endif
ASFLAGS += -D __Unikraft__ -DUK_CODENAME="$(UK_CODENAME)"
ASFLAGS += -DUK_VERSION=$(UK_VERSION).$(UK_SUBVERSION)
diff --git a/plat/kvm/Linker.uk b/plat/kvm/Linker.uk
index 8ed25260..d68f908e 100644
--- a/plat/kvm/Linker.uk
+++ b/plat/kvm/Linker.uk
@@ -30,28 +30,23 @@ $(KVM_IMAGE): $(KVM_ALIBS) $(KVM_ALIBS-y) $(KVM_OLIBS)
$(KVM_OLIBS-y) \
$(call build_cmd,OBJCOPY,,$@.o,\
$(OBJCOPY) -w -G kvmos_* -G _libkvmplat_entry $@.ld.o $@.o)
ifneq ($(filter x86_64 arm64,$(CONFIG_UK_ARCH)),)
- $(call build_cmd,LD,,$@,\
+ $(call build_cmd,LD,,$@.dbg,\
$(LD) $(LDFLAGS) $(LDFLAGS-y) \
$(KVM_LDFLAGS) $(KVM_LDFLAGS-y) \
-Wl$(comma)-dT$(comma)$(call strip,$(KVM_LDSCRIPT)) \
$(KVM_LD_SCRIPT_FLAGS) \
- $@.o -o $@)
-ifeq ($(CONFIG_OPTIMIZE_DBGFILE),y)
- $(call build_cmd,OBJCOPY,,$@.dbg,\
- $(OBJCOPY) --only-keep-debug $@ $@.dbg)
-endif
+ $@.o -o $@.dbg)
+ $(call verbose_cmd,SCSTRIP,$(notdir $@),\
+ $(SCRIPTS_DIR)/sect-strip.py \
+ $(SECT_STRIP_FLAGS) $(SECT_STRIP_FLAGS-y) \
+ --with-objcopy=$(OBJCOPY) \
+ $@.dbg -o $@)
+ $(call verbose_cmd,STRIP,$(notdir $@), $(STRIP) -s $@)
+
ifeq ($(CONFIG_OPTIMIZE_SYMFILE),y)
$(call build_cmd,NM,,$@.sym,\
- $(NM) -n $@ > $@.sym)
+ $(NM) -n $@.dbg > $@.sym)
endif
-# TODO: We have to revisit stripping of KVM binaries. We noticed that sometimes
-# the images are broken and cannot be boot with QEMU's direct kernel boot
-# option (fread() error is returned).
-#
-#ifeq ($(CONFIG_OPTIMIZE_STRIP),y)
-# $(call verbose_cmd,STRIP,$(notdir $@),\
-# $(STRIP) -s $@)
-#endif
$(call build_cmd,GZ,,$@.gz,\
$(GZIP) -f -9 -c $@ >$@.gz)
endif
diff --git a/plat/linuxu/Linker.uk b/plat/linuxu/Linker.uk
index 20ebfc05..dcdd3be2 100644
--- a/plat/linuxu/Linker.uk
+++ b/plat/linuxu/Linker.uk
@@ -12,7 +12,7 @@ LINUXU_LD_SCRIPT_FLAGS := $(addprefix -Wl$(comma)-T$(comma),\
$(LINUXU_IMAGE): $(LINUXU_ALIBS) $(LINUXU_ALIBS-y) \
$(LINUXU_OLIBS) $(LINUXU_OLIBS-y) \
$(UK_ALIBS) $(UK_ALIBS-y) $(UK_OLIBS) $(UK_OLIBS-y)
- $(call build_cmd,LD,,$@,\
+ $(call build_cmd,LD,,$@.dbg,\
$(LD) $(LDFLAGS) $(LDFLAGS-y) \
$(LINUXU_LDFLAGS) $(LINUXU_LDFLAGS-y) \
$(LINUXU_OLIBS) $(LINUXU_OLIBS-y) \
@@ -22,18 +22,16 @@ $(LINUXU_IMAGE): $(LINUXU_ALIBS) $(LINUXU_ALIBS-y) \
$(UK_ALIBS) $(UK_ALIBS-y) \
-Wl$(comma)--end-group \
$(LINUXU_LD_SCRIPT_FLAGS) \
- -o $@)
-ifeq ($(CONFIG_OPTIMIZE_DBGFILE),y)
- $(call build_cmd,OBJCOPY,,$@.dbg,\
- $(OBJCOPY) --only-keep-debug $@ $@.dbg)
-endif
+ -o $@.dbg)
+ $(call verbose_cmd,SCSTRIP,$(notdir $@),\
+ $(SCRIPTS_DIR)/sect-strip.py \
+ $(SECT_STRIP_FLAGS) $(SECT_STRIP_FLAGS-y) \
+ --with-objcopy=$(OBJCOPY) \
+ $@.dbg -o $@)
+ $(call verbose_cmd,STRIP,$(notdir $@), $(STRIP) -s $@)
ifeq ($(CONFIG_OPTIMIZE_SYMFILE),y)
$(call build_cmd,NM,,$@.sym,\
- $(NM) -n $@ > $@.sym)
-endif
-ifeq ($(CONFIG_OPTIMIZE_STRIP),y)
- $(call verbose_cmd,STRIP,$(notdir $@),\
- $(STRIP) -s $@)
+ $(NM) -n $@.dbg > $@.sym)
endif
# register image to the build
diff --git a/plat/xen/Linker.uk b/plat/xen/Linker.uk
index bcbdc00f..3a4a7717 100644
--- a/plat/xen/Linker.uk
+++ b/plat/xen/Linker.uk
@@ -28,44 +28,39 @@ $(XEN_IMAGE): $(XEN_ALIBS) $(XEN_ALIBS-y) $(XEN_OLIBS)
$(XEN_OLIBS-y) \
$(call build_cmd,OBJCOPY,,$@.o,\
$(OBJCOPY) -w -G xenos_* -G _libxenplat_start $@.ld.o $@.o)
ifeq (arm,$(CONFIG_UK_ARCH))
- $(call build_cmd,LD,,$@.elf,\
+ $(call build_cmd,LD,,$@.elf.dbg,\
$(LD) $(LDFLAGS) $(LDFLAGS-y) $(XEN_LDFLAGS) $(XEN_LDFLAGS-y) \
-Wl$(comma)-dT$(comma)$(call strip,$(XEN_LDSCRIPT)) \
$(XEN_LD_SCRIPT_FLAGS) \
- $@.o -o $@.elf)
-ifeq ($(CONFIG_OPTIMIZE_DBGFILE),y)
- $(call build_cmd,OBJCOPY,,$@.dbg,\
- $(OBJCOPY) --only-keep-debug $@.elf $@.dbg)
-endif
+ $@.o -o $@.elf.dbg)
+ $(call verbose_cmd,SCSTRIP,$(notdir $@.elf),\
+ $(SCRIPTS_DIR)/sect-strip.py \
+ $(SECT_STRIP_FLAGS) $(SECT_STRIP_FLAGS-y) \
+ --with-objcopy=$(OBJCOPY) \
+ $@.elf.dbg -o $@.elf)
+ $(call verbose_cmd,STRIP,$(notdir $@.elf), $(STRIP) -s $@.elf)
ifeq ($(CONFIG_OPTIMIZE_SYMFILE),y)
$(call build_cmd,NM,,$@.sym,\
- $(NM) -n $@.elf > $@.sym)
-endif
-ifeq ($(CONFIG_OPTIMIZE_STRIP),y)
- $(call verbose_cmd,STRIP,$(notdir $@),\
- $(STRIP) -s $@.elf)
+ $(NM) -n $@.elf.dbg > $@.sym)
endif
$(call build_cmd,OBJCOPY,,$@,\
$(OBJCOPY) -O binary $@.elf $@)
$(call build_cmd,GZ,,$@.gz,\
$(GZIP) -f -9 -c $@ >$@.gz)
else
- $(call build_cmd,LD,,$@,\
+ $(call build_cmd,LD,,$@.dbg,\
$(LD) $(LDFLAGS) $(LDFLAGS-y) $(XEN_LDFLAGS) $(XEN_LDFLAGS-y) \
-Wl$(comma)-dT$(comma)$(call strip,$(XEN_LDSCRIPT)) \
$(XEN_LD_SCRIPT_FLAGS) \
- $@.o -o $@)
-ifeq ($(CONFIG_OPTIMIZE_DBGFILE),y)
- $(call build_cmd,OBJCOPY,,$@.dbg,\
- $(OBJCOPY) --only-keep-debug $@ $@.dbg)
-endif
+ $@.o -o $@.dbg)
+ $(call verbose_cmd,SCSTRIP,$(notdir $@),\
+ $(SCRIPTS_DIR)/sect-strip.py \
+ $(SECT_STRIP_FLAGS) $(SECT_STRIP_FLAGS-y) \
+ $@.dbg -o $@)
+ $(call verbose_cmd,STRIP,$(notdir $@), $(STRIP) -s $@)
ifeq ($(CONFIG_OPTIMIZE_SYMFILE),y)
$(call build_cmd,NM,,$@.sym,\
- $(NM) -n $@ > $@.sym)
-endif
-ifeq ($(CONFIG_OPTIMIZE_STRIP),y)
- $(call verbose_cmd,STRIP,$(notdir $@),\
- $(STRIP) -s $@)
+ $(NM) -n $@.dbg > $@.sym)
endif
$(call build_cmd,GZ,,$@.gz,\
$(GZIP) -f -9 -c $@ >$@.gz)
@@ -78,6 +73,7 @@ UK_IMAGES-$(CONFIG_PLAT_XEN) += $(XEN_IMAGE)
LIBXENPLAT_CLEAN += $(call build_clean,$(XEN_IMAGE).ld.o)
LIBXENPLAT_CLEAN += $(call build_clean,$(XEN_IMAGE).o)
LIBXENPLAT_CLEAN += $(call build_clean,$(XEN_IMAGE).elf)
+LIBXENPLAT_CLEAN += $(call build_clean,$(XEN_IMAGE).elf.dbg)
LIBXENPLAT_CLEAN += $(call build_clean,$(XEN_IMAGE).gz)
LIBXENPLAT_CLEAN += $(call build_clean,$(XEN_IMAGE).dbg)
LIBXENPLAT_CLEAN += $(call build_clean,$(XEN_IMAGE).sym)
diff --git a/support/scripts/sect-strip.py b/support/scripts/sect-strip.py
new file mode 100755
index 00000000..49f821f4
--- /dev/null
+++ b/support/scripts/sect-strip.py
@@ -0,0 +1,87 @@
+#!/usr/bin/env python3
+#
+# Copyright (c) 2019, NEC Laboratories Europe GmbH, NEC Corporation.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+# General Public License for more details.
+#
+# This nonsense exists because objcopy and strip are complaining if
+# the last section within the segment is removed. This is just a
+# script which suppresses this message.
+
+import argparse
+import subprocess
+import sys
+import shutil
+
+def format_args(args):
+ def format_arg(arg):
+ if ' ' in arg:
+ return '"%s"' % arg
+ return arg
+
+ return ' '.join(map(format_arg, args))
+
+def main():
+ parser = argparse.ArgumentParser(description="Strip sections gracefully")
+ parser.add_argument("src", help="Source elf to strip")
+ parser.add_argument("-o", "--output", help="Target elf file",
required=True)
+ parser.add_argument("-R", "--remove-section", action='append', default=[],
+ help="Sections to be removed (patterns allowed)")
+ parser.add_argument("--with-objcopy", default="objcopy",
+ help="Specify if a specific objcopy binary should be
used")
+ parser.add_argument("--dry-run", action="store_true",
+ default=False,
+ help="do not change anything, print objcopy command")
+ opt = parser.parse_args()
+
+ cmd = [opt.with_objcopy,
+ opt.src,
+ opt.output,
+ ]
+
+ if len(opt.remove_section) == 0:
+ if not opt.dry_run:
+ shutil.copy(opt.src, opt.output)
+ return
+
+ for i in opt.remove_section:
+ cmd += ['-R', i]
+
+ if opt.dry_run:
+ print(format_args(cmd))
+ return
+
+ proc = subprocess.Popen(cmd,
+ stdout=subprocess.PIPE,
+ stderr=subprocess.STDOUT)
+ _stdout, _ = proc.communicate()
+ _stdout = _stdout.decode().strip()
+
+ if proc.returncode:
+ print("Error occurred while objcopy:", file=sys.stderr)
+ print(_stdout, file=sys.stderr)
+ sys.exit(1)
+
+ filter_str = "warning: Empty loadable segment detected, is this
intentional"
+
+ # If nothing was on stdout, split will produce a list consisting
+ # of one element - empty string. We an want empty list though.
+ if len(_stdout) == 0:
+ lines = []
+ else:
+ lines = _stdout.split('\n')
+
+ lines = filter(lambda a : filter_str not in a, lines)
+ for i in lines:
+ print(i, file=sys.stderr)
+
+if __name__ == '__main__':
+ main()
