'make image_name' needs include/config/auto.conf to show the correct
output because KBUILD_IMAGE depends on CONFIG options, but should not
attempt to resync the configuration.
Signed-off-by: Masahiro Yamada <[email protected]>
---
Makefile | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/Makefile b/Makefile
index 633d2769b6ec..c84a9311df29 100644
--- a/Makefile
+++ b/Makefile
@@ -263,7 +263,8 @@ no-dot-config-targets := $(clean-targets) \
$(version_h) headers headers_% archheaders archscripts \
%asm-generic kernelversion %src-pkg dt_binding_check \
outputmakefile
-no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease
+no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
+ image_name
single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
config-build :=
--
2.27.0
scripts/Kbuild.include is included everywhere, but macros such as
cc-option are needed by build targets only.
For example, when 'make clean' traverses the tree, it does not need
to evaluate $(call cc-option,).
Split cc-option, ld-option, etc. to scripts/Makefile.compiler, which
is only included from the top Makefile and scripts/Makefile.build.
Signed-off-by: Masahiro Yamada <[email protected]>
---
Makefile | 4 ++
scripts/Kbuild.include | 80 ---------------------------------------
scripts/Makefile.build | 1 +
scripts/Makefile.compiler | 77 +++++++++++++++++++++++++++++++++++++
4 files changed, 82 insertions(+), 80 deletions(-)
create mode 100644 scripts/Makefile.compiler
diff --git a/Makefile b/Makefile
index 2253e31a6bcf..eec7a94f5c33 100644
--- a/Makefile
+++ b/Makefile
@@ -582,6 +582,10 @@ KBUILD_AFLAGS += $(CLANG_FLAGS)
export CLANG_FLAGS
endif
+# Include this also for config targets because some architectures need
+# cc-cross-prefix to determine CROSS_COMPILE.
+include $(srctree)/scripts/Makefile.compiler
+
ifdef config-build
# ===========================================================================
# *config targets only - make sure prerequisites are updated, and descend
diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
index 509e0856d653..82dd1b65b7a8 100644
--- a/scripts/Kbuild.include
+++ b/scripts/Kbuild.include
@@ -67,86 +67,6 @@ define filechk
fi
endef
-######
-# gcc support functions
-# See documentation in Documentation/kbuild/makefiles.rst
-
-# cc-cross-prefix
-# Usage: CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-)
-# Return first <prefix> where a <prefix>gcc is found in PATH.
-# If no gcc found in PATH with listed prefixes return nothing
-#
-# Note: '2>/dev/null' is here to force Make to invoke a shell. Otherwise, it
-# would try to directly execute the shell builtin 'command'. This workaround
-# should be kept for a long time since this issue was fixed only after the
-# GNU Make 4.2.1 release.
-cc-cross-prefix = $(firstword $(foreach c, $(1), \
- $(if $(shell command -v -- $(c)gcc 2>/dev/null), $(c))))
-
-# output directory for tests below
-TMPOUT = $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_$$$$
-
-# try-run
-# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise)
-# Exit code chooses option. "$$TMP" serves as a temporary file and is
-# automatically cleaned up.
-try-run = $(shell set -e; \
- TMP=$(TMPOUT)/tmp; \
- TMPO=$(TMPOUT)/tmp.o; \
- mkdir -p $(TMPOUT); \
- trap "rm -rf $(TMPOUT)" EXIT; \
- if ($(1)) >/dev/null 2>&1; \
- then echo "$(2)"; \
- else echo "$(3)"; \
- fi)
-
-# as-option
-# Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)
-
-as-option = $(call try-run,\
- $(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2))
-
-# as-instr
-# Usage: cflags-y += $(call as-instr,instr,option1,option2)
-
-as-instr = $(call try-run,\
- printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))
-
-# __cc-option
-# Usage: MY_CFLAGS += $(call __cc-option,$(CC),$(MY_CFLAGS),-march=winchip-c6,-march=i586)
-__cc-option = $(call try-run,\
- $(1) -Werror $(2) $(3) -c -x c /dev/null -o "$$TMP",$(3),$(4))
-
-# cc-option
-# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)
-
-cc-option = $(call __cc-option, $(CC),\
- $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS),$(1),$(2))
-
-# cc-option-yn
-# Usage: flag := $(call cc-option-yn,-march=winchip-c6)
-cc-option-yn = $(call try-run,\
- $(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)
-
-# cc-disable-warning
-# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
-cc-disable-warning = $(call try-run,\
- $(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
-
-# cc-ifversion
-# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
-cc-ifversion = $(shell [ $(CONFIG_GCC_VERSION)0 $(1) $(2)000 ] && echo $(3) || echo $(4))
-
-# ld-option
-# Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y)
-ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3))
-
-# ld-ifversion
-# Usage: $(call ld-ifversion, -ge, 22252, y)
-ld-ifversion = $(shell [ $(CONFIG_LD_VERSION)0 $(1) $(2)0 ] && echo $(3) || echo $(4))
-
-######
-
###
# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
# Usage:
diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 750d6d5225af..d74d3383666e 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -36,6 +36,7 @@ subdir-ccflags-y :=
-include include/config/auto.conf
include $(srctree)/scripts/Kbuild.include
+include $(srctree)/scripts/Makefile.compiler
# The filename Kbuild has precedence over Makefile
kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
diff --git a/scripts/Makefile.compiler b/scripts/Makefile.compiler
new file mode 100644
index 000000000000..5f759ecc4f04
--- /dev/null
+++ b/scripts/Makefile.compiler
@@ -0,0 +1,77 @@
+######
+# gcc support functions
+# See documentation in Documentation/kbuild/makefiles.rst
+
+# cc-cross-prefix
+# Usage: CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-)
+# Return first <prefix> where a <prefix>gcc is found in PATH.
+# If no gcc found in PATH with listed prefixes return nothing
+#
+# Note: '2>/dev/null' is here to force Make to invoke a shell. Otherwise, it
+# would try to directly execute the shell builtin 'command'. This workaround
+# should be kept for a long time since this issue was fixed only after the
+# GNU Make 4.2.1 release.
+cc-cross-prefix = $(firstword $(foreach c, $(1), \
+ $(if $(shell command -v -- $(c)gcc 2>/dev/null), $(c))))
+
+# output directory for tests below
+TMPOUT = $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_$$$$
+
+# try-run
+# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise)
+# Exit code chooses option. "$$TMP" serves as a temporary file and is
+# automatically cleaned up.
+try-run = $(shell set -e; \
+ TMP=$(TMPOUT)/tmp; \
+ TMPO=$(TMPOUT)/tmp.o; \
+ mkdir -p $(TMPOUT); \
+ trap "rm -rf $(TMPOUT)" EXIT; \
+ if ($(1)) >/dev/null 2>&1; \
+ then echo "$(2)"; \
+ else echo "$(3)"; \
+ fi)
+
+# as-option
+# Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)
+
+as-option = $(call try-run,\
+ $(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2))
+
+# as-instr
+# Usage: cflags-y += $(call as-instr,instr,option1,option2)
+
+as-instr = $(call try-run,\
+ printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))
+
+# __cc-option
+# Usage: MY_CFLAGS += $(call __cc-option,$(CC),$(MY_CFLAGS),-march=winchip-c6,-march=i586)
+__cc-option = $(call try-run,\
+ $(1) -Werror $(2) $(3) -c -x c /dev/null -o "$$TMP",$(3),$(4))
+
+# cc-option
+# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)
+
+cc-option = $(call __cc-option, $(CC),\
+ $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS),$(1),$(2))
+
+# cc-option-yn
+# Usage: flag := $(call cc-option-yn,-march=winchip-c6)
+cc-option-yn = $(call try-run,\
+ $(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)
+
+# cc-disable-warning
+# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
+cc-disable-warning = $(call try-run,\
+ $(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
+
+# cc-ifversion
+# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
+cc-ifversion = $(shell [ $(CONFIG_GCC_VERSION)0 $(1) $(2)000 ] && echo $(3) || echo $(4))
+
+# ld-option
+# Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y)
+ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3))
+
+# ld-ifversion
+# Usage: $(call ld-ifversion, -ge, 22252, y)
+ld-ifversion = $(shell [ $(CONFIG_LD_VERSION)0 $(1) $(2)0 ] && echo $(3) || echo $(4))
--
2.27.0
VPATH is used in Kbuild to make pattern rules to search for prerequisites
in both $(objtree) and $(srctree). Some source files may not be real
sources, but generated by tools such as flex, bison, perl.
In contrast, I doubt the benefit of --include-dir=$(abs_srctree) because
it is always clear which Makefiles are real sources, and which are not.
So, my hope is to add $(srctree)/ prefix to all check-in Makefiles,
then remove --include-dir=$(abs_srctree) flag in the future.
I am touching only some Kbuild core parts for now. Treewide fixes will
be needed to achieve this goal.
Signed-off-by: Masahiro Yamada <[email protected]>
---
Makefile | 8 ++++----
scripts/Makefile.asm-generic | 4 ++--
scripts/Makefile.build | 8 ++++----
scripts/Makefile.clean | 2 +-
scripts/Makefile.dtbinst | 2 +-
scripts/Makefile.headersinst | 2 +-
scripts/Makefile.modinst | 2 +-
scripts/Makefile.modpost | 4 ++--
scripts/Makefile.modsign | 2 +-
9 files changed, 17 insertions(+), 17 deletions(-)
diff --git a/Makefile b/Makefile
index c84a9311df29..2253e31a6bcf 100644
--- a/Makefile
+++ b/Makefile
@@ -338,14 +338,14 @@ __build_one_by_one:
else # !mixed-build
-include scripts/Kbuild.include
+include $(srctree)/scripts/Kbuild.include
# Read KERNELRELEASE from include/config/kernel.release (if it exists)
KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
-include scripts/subarch.include
+include $(srctree)/scripts/subarch.include
# Cross compiling and selecting different set of gcc/bin-utils
# ---------------------------------------------------------------------------
@@ -590,7 +590,7 @@ ifdef config-build
# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
# KBUILD_DEFCONFIG may point out an alternative default configuration
# used for 'make defconfig'
-include arch/$(SRCARCH)/Makefile
+include $(srctree)/arch/$(SRCARCH)/Makefile
export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
config: outputmakefile scripts_basic FORCE
@@ -677,7 +677,7 @@ RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc
export RETPOLINE_CFLAGS
export RETPOLINE_VDSO_CFLAGS
-include arch/$(SRCARCH)/Makefile
+include $(srctree)/arch/$(SRCARCH)/Makefile
ifdef need-config
ifdef may-sync-config
diff --git a/scripts/Makefile.asm-generic b/scripts/Makefile.asm-generic
index 82ad63dcd62b..1d501c57f9ef 100644
--- a/scripts/Makefile.asm-generic
+++ b/scripts/Makefile.asm-generic
@@ -14,10 +14,10 @@ src := $(subst /generated,,$(obj))
# $(generic)/Kbuild lists mandatory-y. Exclude um since it is a special case.
ifneq ($(SRCARCH),um)
-include $(generic)/Kbuild
+include $(srctree)/$(generic)/Kbuild
endif
-include scripts/Kbuild.include
+include $(srctree)/scripts/Kbuild.include
redundant := $(filter $(mandatory-y) $(generated-y), $(generic-y))
redundant += $(foreach f, $(generic-y), $(if $(wildcard $(srctree)/$(src)/$(f)),$(f)))
diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 1b6094a13034..750d6d5225af 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -35,27 +35,27 @@ subdir-ccflags-y :=
# Read auto.conf if it exists, otherwise ignore
-include include/config/auto.conf
-include scripts/Kbuild.include
+include $(srctree)/scripts/Kbuild.include
# The filename Kbuild has precedence over Makefile
kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
kbuild-file := $(if $(wildcard $(kbuild-dir)/Kbuild),$(kbuild-dir)/Kbuild,$(kbuild-dir)/Makefile)
include $(kbuild-file)
-include scripts/Makefile.lib
+include $(srctree)/scripts/Makefile.lib
# Do not include hostprogs rules unless needed.
# $(sort ...) is used here to remove duplicated words and excessive spaces.
hostprogs := $(sort $(hostprogs))
ifneq ($(hostprogs),)
-include scripts/Makefile.host
+include $(srctree)/scripts/Makefile.host
endif
# Do not include userprogs rules unless needed.
# $(sort ...) is used here to remove duplicated words and excessive spaces.
userprogs := $(sort $(userprogs))
ifneq ($(userprogs),)
-include scripts/Makefile.userprogs
+include $(srctree)/scripts/Makefile.userprogs
endif
ifndef obj
diff --git a/scripts/Makefile.clean b/scripts/Makefile.clean
index 22a8172bce1f..fd6175322470 100644
--- a/scripts/Makefile.clean
+++ b/scripts/Makefile.clean
@@ -8,7 +8,7 @@ src := $(obj)
PHONY := __clean
__clean:
-include scripts/Kbuild.include
+include $(srctree)/scripts/Kbuild.include
# The filename Kbuild has precedence over Makefile
kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
diff --git a/scripts/Makefile.dtbinst b/scripts/Makefile.dtbinst
index ba01f5ba2517..190d781e84f4 100644
--- a/scripts/Makefile.dtbinst
+++ b/scripts/Makefile.dtbinst
@@ -14,7 +14,7 @@ PHONY := __dtbs_install
__dtbs_install:
include include/config/auto.conf
-include scripts/Kbuild.include
+include $(srctree)/scripts/Kbuild.include
include $(src)/Makefile
dtbs := $(addprefix $(dst)/, $(dtb-y) $(if $(CONFIG_OF_ALL_DTBS),$(dtb-)))
diff --git a/scripts/Makefile.headersinst b/scripts/Makefile.headersinst
index 708fbd08a2c5..029d85bb0b23 100644
--- a/scripts/Makefile.headersinst
+++ b/scripts/Makefile.headersinst
@@ -12,7 +12,7 @@
PHONY := __headers
__headers:
-include scripts/Kbuild.include
+include $(srctree)/scripts/Kbuild.include
src := $(srctree)/$(obj)
gen := $(objtree)/$(subst include/,include/generated/,$(obj))
diff --git a/scripts/Makefile.modinst b/scripts/Makefile.modinst
index 5a4579e76485..ad1981233d0b 100644
--- a/scripts/Makefile.modinst
+++ b/scripts/Makefile.modinst
@@ -6,7 +6,7 @@
PHONY := __modinst
__modinst:
-include scripts/Kbuild.include
+include $(srctree)/scripts/Kbuild.include
modules := $(sort $(shell cat $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)modules.order))
diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost
index 066beffca09a..df57e259fac3 100644
--- a/scripts/Makefile.modpost
+++ b/scripts/Makefile.modpost
@@ -41,10 +41,10 @@ PHONY := __modpost
__modpost:
include include/config/auto.conf
-include scripts/Kbuild.include
+include $(srctree)/scripts/Kbuild.include
# for ld_flags
-include scripts/Makefile.lib
+include $(srctree)/scripts/Makefile.lib
MODPOST = scripts/mod/modpost \
$(if $(CONFIG_MODVERSIONS),-m) \
diff --git a/scripts/Makefile.modsign b/scripts/Makefile.modsign
index d7325cefe709..ddf9b5ca77d7 100644
--- a/scripts/Makefile.modsign
+++ b/scripts/Makefile.modsign
@@ -6,7 +6,7 @@
PHONY := __modsign
__modsign:
-include scripts/Kbuild.include
+include $(srctree)/scripts/Kbuild.include
modules := $(sort $(shell cat modules.order))
--
2.27.0
Since commit f2f02ebd8f38 ("kbuild: improve cc-option to clean up all
temporary files"), running 'make kernelversion' in a read-only source
tree emits a bunch of warnings:
mkdir: cannot create directory '.tmp_12345': Permission denied
Non-build targets such as kernelversion, clean, help, etc. do not
need to evaluate $(call cc-option,) and friends. Do not include
Makefile.compiler so $(call cc-option,) becomes no-op.
This not only fix the warnings, but also runs non-build targets much
faster.
Basically, all installation targets should also be non-build targets.
Unfortunately, vdso_install requires the compiler because it builds
vdso before installtion. This is a problem that must be fixed by a
separate patch.
Signed-off-by: Masahiro Yamada <[email protected]>
---
I am not adding Reported-by for now because a reporter sent me
an email privately.
If he allows me to add Reported-by, I will add it to record
the credit.
(Perhaps, another person might have reported a similar issue
somewhere, but my memory is obsure. I cannot recall it.)
Makefile | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/Makefile b/Makefile
index eec7a94f5c33..20724711dc71 100644
--- a/Makefile
+++ b/Makefile
@@ -263,6 +263,10 @@ no-dot-config-targets := $(clean-targets) \
$(version_h) headers headers_% archheaders archscripts \
%asm-generic kernelversion %src-pkg dt_binding_check \
outputmakefile
+# Installation targets should not require compiler. Unfortunately, vdso_install
+# is an exception where build artifacts may be updated. This must be fixed.
+no-compiler-targets := $(no-dot-config-targets) install dtbs_install \
+ headers_install modules_install kernelrelease image_name
no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
image_name
single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
@@ -270,6 +274,7 @@ single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
config-build :=
mixed-build :=
need-config := 1
+need-compiler := 1
may-sync-config := 1
single-build :=
@@ -279,6 +284,12 @@ ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
endif
endif
+ifneq ($(filter $(no-compiler-targets), $(MAKECMDGOALS)),)
+ ifeq ($(filter-out $(no-compiler-targets), $(MAKECMDGOALS)),)
+ need-compiler :=
+ endif
+endif
+
ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
may-sync-config :=
@@ -584,7 +595,9 @@ endif
# Include this also for config targets because some architectures need
# cc-cross-prefix to determine CROSS_COMPILE.
+ifdef need-compiler
include $(srctree)/scripts/Makefile.compiler
+endif
ifdef config-build
# ===========================================================================
--
2.27.0
On Sun, Feb 28, 2021 at 3:10 PM Masahiro Yamada <[email protected]> wrote:
>
> Since commit f2f02ebd8f38 ("kbuild: improve cc-option to clean up all
> temporary files"), running 'make kernelversion' in a read-only source
> tree emits a bunch of warnings:
>
> mkdir: cannot create directory '.tmp_12345': Permission denied
>
> Non-build targets such as kernelversion, clean, help, etc. do not
> need to evaluate $(call cc-option,) and friends. Do not include
> Makefile.compiler so $(call cc-option,) becomes no-op.
>
> This not only fix the warnings, but also runs non-build targets much
> faster.
>
> Basically, all installation targets should also be non-build targets.
> Unfortunately, vdso_install requires the compiler because it builds
> vdso before installtion. This is a problem that must be fixed by a
> separate patch.
>
> Signed-off-by: Masahiro Yamada <[email protected]>
> ---
>
> I am not adding Reported-by for now because a reporter sent me
> an email privately.
>
> If he allows me to add Reported-by, I will add it to record
> the credit.
>
> (Perhaps, another person might have reported a similar issue
> somewhere, but my memory is obsure. I cannot recall it.)
>
Now, I got acknowledge to add this:
Reported-by: Israel Tsadok <[email protected]>
> Makefile | 13 +++++++++++++
> 1 file changed, 13 insertions(+)
>
> diff --git a/Makefile b/Makefile
> index eec7a94f5c33..20724711dc71 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -263,6 +263,10 @@ no-dot-config-targets := $(clean-targets) \
> $(version_h) headers headers_% archheaders archscripts \
> %asm-generic kernelversion %src-pkg dt_binding_check \
> outputmakefile
> +# Installation targets should not require compiler. Unfortunately, vdso_install
> +# is an exception where build artifacts may be updated. This must be fixed.
> +no-compiler-targets := $(no-dot-config-targets) install dtbs_install \
> + headers_install modules_install kernelrelease image_name
> no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
> image_name
> single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
> @@ -270,6 +274,7 @@ single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
> config-build :=
> mixed-build :=
> need-config := 1
> +need-compiler := 1
> may-sync-config := 1
> single-build :=
>
> @@ -279,6 +284,12 @@ ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
> endif
> endif
>
> +ifneq ($(filter $(no-compiler-targets), $(MAKECMDGOALS)),)
> + ifeq ($(filter-out $(no-compiler-targets), $(MAKECMDGOALS)),)
> + need-compiler :=
> + endif
> +endif
> +
> ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
> ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
> may-sync-config :=
> @@ -584,7 +595,9 @@ endif
>
> # Include this also for config targets because some architectures need
> # cc-cross-prefix to determine CROSS_COMPILE.
> +ifdef need-compiler
> include $(srctree)/scripts/Makefile.compiler
> +endif
>
> ifdef config-build
> # ===========================================================================
> --
> 2.27.0
>
--
Best Regards
Masahiro Yamada
On Sun, Feb 28, 2021 at 3:10 PM Masahiro Yamada <[email protected]> wrote:
>
> 'make image_name' needs include/config/auto.conf to show the correct
> output because KBUILD_IMAGE depends on CONFIG options, but should not
> attempt to resync the configuration.
>
> Signed-off-by: Masahiro Yamada <[email protected]>
> ---
All applied to linux-kbuild.
> Makefile | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/Makefile b/Makefile
> index 633d2769b6ec..c84a9311df29 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -263,7 +263,8 @@ no-dot-config-targets := $(clean-targets) \
> $(version_h) headers headers_% archheaders archscripts \
> %asm-generic kernelversion %src-pkg dt_binding_check \
> outputmakefile
> -no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease
> +no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
> + image_name
> single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
>
> config-build :=
> --
> 2.27.0
>
--
Best Regards
Masahiro Yamada
On Sun, Feb 28, 2021 at 03:10:28PM +0900, Masahiro Yamada wrote:
> Since commit f2f02ebd8f38 ("kbuild: improve cc-option to clean up all
> temporary files"), running 'make kernelversion' in a read-only source
> tree emits a bunch of warnings:
>
> mkdir: cannot create directory '.tmp_12345': Permission denied
>
> Non-build targets such as kernelversion, clean, help, etc. do not
> need to evaluate $(call cc-option,) and friends. Do not include
> Makefile.compiler so $(call cc-option,) becomes no-op.
>
> This not only fix the warnings, but also runs non-build targets much
> faster.
>
> Basically, all installation targets should also be non-build targets.
> Unfortunately, vdso_install requires the compiler because it builds
> vdso before installtion. This is a problem that must be fixed by a
> separate patch.
>
> Signed-off-by: Masahiro Yamada <[email protected]>
> ---
>
> I am not adding Reported-by for now because a reporter sent me
> an email privately.
>
> If he allows me to add Reported-by, I will add it to record
> the credit.
>
> (Perhaps, another person might have reported a similar issue
> somewhere, but my memory is obsure. I cannot recall it.)
>
>
> Makefile | 13 +++++++++++++
> 1 file changed, 13 insertions(+)
>
> diff --git a/Makefile b/Makefile
> index eec7a94f5c33..20724711dc71 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -263,6 +263,10 @@ no-dot-config-targets := $(clean-targets) \
> $(version_h) headers headers_% archheaders archscripts \
> %asm-generic kernelversion %src-pkg dt_binding_check \
> outputmakefile
> +# Installation targets should not require compiler. Unfortunately, vdso_install
> +# is an exception where build artifacts may be updated. This must be fixed.
> +no-compiler-targets := $(no-dot-config-targets) install dtbs_install \
> + headers_install modules_install kernelrelease image_name
> no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
> image_name
> single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
> @@ -270,6 +274,7 @@ single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
> config-build :=
> mixed-build :=
> need-config := 1
> +need-compiler := 1
> may-sync-config := 1
> single-build :=
>
> @@ -279,6 +284,12 @@ ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
> endif
> endif
>
> +ifneq ($(filter $(no-compiler-targets), $(MAKECMDGOALS)),)
> + ifeq ($(filter-out $(no-compiler-targets), $(MAKECMDGOALS)),)
> + need-compiler :=
> + endif
> +endif
> +
> ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
> ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
> may-sync-config :=
> @@ -584,7 +595,9 @@ endif
>
> # Include this also for config targets because some architectures need
> # cc-cross-prefix to determine CROSS_COMPILE.
> +ifdef need-compiler
> include $(srctree)/scripts/Makefile.compiler
> +endif
>
> ifdef config-build
> # ===========================================================================
> --
> 2.27.0
>
Hi Masahiro,
I see a new warning in my builds on arm64 now when running
'modules_install' or 'dtbs_install' because ld-option evaluates to
nothing, which triggers the warning in arch/arm64/Makefile:
$ make -skj"$(nproc)" \
ARCH=arm64 \
CROSS_COMPILE=aarch64-linux- \
INSTALL_DTBS_PATH=rootfs \
INSTALL_MOD_PATH=rootfs \
O=build/arm64 \
distclean defconfig all modules_install dtbs_install
...
/home/nathan/cbl/src/linux-next/arch/arm64/Makefile:25: ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum
/home/nathan/cbl/src/linux-next/arch/arm64/Makefile:25: ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum
$ sed -n '23,29p' arch/arm64/Makefile
ifeq ($(CONFIG_ARM64_ERRATUM_843419),y)
ifeq ($(call ld-option, --fix-cortex-a53-843419),)
$(warning ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum)
else
LDFLAGS_vmlinux += --fix-cortex-a53-843419
endif
endif
I am not sure how this should be resolved, hence just the report.
Cheers,
Nathan
(CC: Will and ARM ML)
On Fri, Mar 19, 2021 at 6:14 AM Nathan Chancellor <[email protected]> wrote:
>
> On Sun, Feb 28, 2021 at 03:10:28PM +0900, Masahiro Yamada wrote:
> > Since commit f2f02ebd8f38 ("kbuild: improve cc-option to clean up all
> > temporary files"), running 'make kernelversion' in a read-only source
> > tree emits a bunch of warnings:
> >
> > mkdir: cannot create directory '.tmp_12345': Permission denied
> >
> > Non-build targets such as kernelversion, clean, help, etc. do not
> > need to evaluate $(call cc-option,) and friends. Do not include
> > Makefile.compiler so $(call cc-option,) becomes no-op.
> >
> > This not only fix the warnings, but also runs non-build targets much
> > faster.
> >
> > Basically, all installation targets should also be non-build targets.
> > Unfortunately, vdso_install requires the compiler because it builds
> > vdso before installtion. This is a problem that must be fixed by a
> > separate patch.
> >
> > Signed-off-by: Masahiro Yamada <[email protected]>
> > ---
> >
> > I am not adding Reported-by for now because a reporter sent me
> > an email privately.
> >
> > If he allows me to add Reported-by, I will add it to record
> > the credit.
> >
> > (Perhaps, another person might have reported a similar issue
> > somewhere, but my memory is obsure. I cannot recall it.)
> >
> >
> > Makefile | 13 +++++++++++++
> > 1 file changed, 13 insertions(+)
> >
> > diff --git a/Makefile b/Makefile
> > index eec7a94f5c33..20724711dc71 100644
> > --- a/Makefile
> > +++ b/Makefile
> > @@ -263,6 +263,10 @@ no-dot-config-targets := $(clean-targets) \
> > $(version_h) headers headers_% archheaders archscripts \
> > %asm-generic kernelversion %src-pkg dt_binding_check \
> > outputmakefile
> > +# Installation targets should not require compiler. Unfortunately, vdso_install
> > +# is an exception where build artifacts may be updated. This must be fixed.
> > +no-compiler-targets := $(no-dot-config-targets) install dtbs_install \
> > + headers_install modules_install kernelrelease image_name
> > no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
> > image_name
> > single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
> > @@ -270,6 +274,7 @@ single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
> > config-build :=
> > mixed-build :=
> > need-config := 1
> > +need-compiler := 1
> > may-sync-config := 1
> > single-build :=
> >
> > @@ -279,6 +284,12 @@ ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
> > endif
> > endif
> >
> > +ifneq ($(filter $(no-compiler-targets), $(MAKECMDGOALS)),)
> > + ifeq ($(filter-out $(no-compiler-targets), $(MAKECMDGOALS)),)
> > + need-compiler :=
> > + endif
> > +endif
> > +
> > ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
> > ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
> > may-sync-config :=
> > @@ -584,7 +595,9 @@ endif
> >
> > # Include this also for config targets because some architectures need
> > # cc-cross-prefix to determine CROSS_COMPILE.
> > +ifdef need-compiler
> > include $(srctree)/scripts/Makefile.compiler
> > +endif
> >
> > ifdef config-build
> > # ===========================================================================
> > --
> > 2.27.0
> >
>
> Hi Masahiro,
>
> I see a new warning in my builds on arm64 now when running
> 'modules_install' or 'dtbs_install' because ld-option evaluates to
> nothing, which triggers the warning in arch/arm64/Makefile:
>
> $ make -skj"$(nproc)" \
> ARCH=arm64 \
> CROSS_COMPILE=aarch64-linux- \
> INSTALL_DTBS_PATH=rootfs \
> INSTALL_MOD_PATH=rootfs \
> O=build/arm64 \
> distclean defconfig all modules_install dtbs_install
> ...
> /home/nathan/cbl/src/linux-next/arch/arm64/Makefile:25: ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum
> /home/nathan/cbl/src/linux-next/arch/arm64/Makefile:25: ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum
>
> $ sed -n '23,29p' arch/arm64/Makefile
> ifeq ($(CONFIG_ARM64_ERRATUM_843419),y)
> ifeq ($(call ld-option, --fix-cortex-a53-843419),)
> $(warning ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum)
> else
> LDFLAGS_vmlinux += --fix-cortex-a53-843419
> endif
> endif
>
> I am not sure how this should be resolved, hence just the report.
>
> Cheers,
> Nathan
I see this a few lines below:
ifeq ($(CONFIG_ARM64_USE_LSE_ATOMICS), y)
ifneq ($(CONFIG_ARM64_LSE_ATOMICS), y)
$(warning LSE atomics not supported by binutils)
endif
endif
We can move ld-option evaluation to Kconfig.
ifeq ($(CONFIG_ARM64_ERRATUM_843419),y)
ifneq ($(CONFIG_ARM64_LD_HAS_FIX_ERRATUM_843419,y))
$(warning ld does not support --fix-cortex-a53-843419; kernel may be
susceptible to erratum)
else
LDFLAGS_vmlinux += --fix-cortex-a53-843419
endif
endif
I do not know what CONFIG name is preferred.
--
Best Regards
Masahiro Yamada
On 2/28/21 7:10 AM, Masahiro Yamada wrote:
> scripts/Kbuild.include is included everywhere, but macros such as
> cc-option are needed by build targets only.
>
> For example, when 'make clean' traverses the tree, it does not need
> to evaluate $(call cc-option,).
>
> Split cc-option, ld-option, etc. to scripts/Makefile.compiler, which
> is only included from the top Makefile and scripts/Makefile.build.
>
> Signed-off-by: Masahiro Yamada <[email protected]>
This commit broke the KVM selftest compilation under s390 in linux-next
for me. Funny enough the compilation is only broken on Ubuntu, under
Fedora the test fails with an assertion.
FEDORA:
[root@fedora kvm]# ./set_memory_region_test
Allowed number of memory slots: 32767
==== Test Assertion Failure ====
lib/kvm_util.c:142: vm->fd >= 0
pid=1541645 tid=1541645 - Invalid argument
1 0x0000000001002f4b: vm_open at kvm_util.c:142
2 (inlined by) vm_create at kvm_util.c:258
3 0x00000000010015ef: test_add_max_memory_regions at
set_memory_region_test.c:351
4 (inlined by) main at set_memory_region_test.c:397
5 0x000003ffa3d2bb89: ?? ??:0
6 0x00000000010017ad: .annobin_abi_note.c.hot at crt1.o:?
KVM_CREATE_VM ioctl failed, rc: -1 errno: 22
Ubuntu:
make[1]: Leaving directory '/mnt/dev/linux'
gcc -Wall -Wstrict-prototypes -Wuninitialized -O2 -g -std=gnu99
-fno-stack-protector -fno-PIE -I../../../../tools/include
-I../../../../tools/arch/s390/include -I../../../../usr/include/
-Iinclude -Ilib -Iinclude/s390x -I.. -c lib/sparsebit.c -o
/mnt/dev/linux/tools/testing/selftests/kvm/lib/sparsebit.o
gcc -Wall -Wstrict-prototypes -Wuninitialized -O2 -g -std=gnu99
-fno-stack-protector -fno-PIE -I../../../../tools/include
-I../../../../tools/arch/s390/include -I../../../../usr/include/
-Iinclude -Ilib -Iinclude/s390x -I.. -c lib/kvm_util.c -o
/mnt/dev/linux/tools/testing/selftests/kvm/lib/kvm_util.o
gcc -Wall -Wstrict-prototypes -Wuninitialized -O2 -g -std=gnu99
-fno-stack-protector -fno-PIE -I../../../../tools/include
-I../../../../tools/arch/s390/include -I../../../../usr/include/
-Iinclude -Ilib/s390x -Iinclude/s390x -I.. -c
lib/s390x/diag318_test_handler.c -o
/mnt/dev/linux/tools/testing/selftests/kvm/lib/s390x/diag318_test_handler.o
ar crs /mnt/dev/linux/tools/testing/selftests/kvm/libkvm.a
/mnt/dev/linux/tools/testing/selftests/kvm/lib/assert.o
/mnt/dev/linux/tools/testing/selftests/kvm/lib/elf.o
/mnt/dev/linux/tools/testing/selftests/kvm/lib/io.o
/mnt/dev/linux/tools/testing/selftests/kvm/lib/kvm_util.o
/mnt/dev/linux/tools/testing/selftests/kvm/lib/sparsebit.o
/mnt/dev/linux/tools/testing/selftests/kvm/lib/test_util.o
/mnt/dev/linux/tools/testing/selftests/kvm/lib/guest_modes.o
/mnt/dev/linux/tools/testing/selftests/kvm/lib/perf_test_util.o
/mnt/dev/linux/tools/testing/selftests/kvm/lib/s390x/processor.o
/mnt/dev/linux/tools/testing/selftests/kvm/lib/s390x/ucall.o
/mnt/dev/linux/tools/testing/selftests/kvm/lib/s390x/diag318_test_handler.o
gcc -Wall -Wstrict-prototypes -Wuninitialized -O2 -g -std=gnu99
-fno-stack-protector -fno-PIE -I../../../../tools/include
-I../../../../tools/arch/s390/include -I../../../../usr/include/
-Iinclude -Is390x -Iinclude/s390x -I.. -pthread s390x/memop.c
/mnt/dev/linux/tools/testing/selftests/kvm/libkvm.a -o
/mnt/dev/linux/tools/testing/selftests/kvm/s390x/memop
/usr/bin/ld: /tmp/ccFU8WYF.o: `stdout@@GLIBC_2.2' non-PLT reloc for
symbol defined in shared library and accessed from executable (rebuild
file with -fPIC ?)
/usr/bin/ld: final link failed: bad value
collect2: error: ld returned 1 exit status
make: *** [../lib.mk:139:
/mnt/dev/linux/tools/testing/selftests/kvm/s390x/memop] Error 1
> ---
>
> Makefile | 4 ++
> scripts/Kbuild.include | 80 ---------------------------------------
> scripts/Makefile.build | 1 +
> scripts/Makefile.compiler | 77 +++++++++++++++++++++++++++++++++++++
> 4 files changed, 82 insertions(+), 80 deletions(-)
> create mode 100644 scripts/Makefile.compiler
>
> diff --git a/Makefile b/Makefile
> index 2253e31a6bcf..eec7a94f5c33 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -582,6 +582,10 @@ KBUILD_AFLAGS += $(CLANG_FLAGS)
> export CLANG_FLAGS
> endif
>
> +# Include this also for config targets because some architectures need
> +# cc-cross-prefix to determine CROSS_COMPILE.
> +include $(srctree)/scripts/Makefile.compiler
> +
> ifdef config-build
> # ===========================================================================
> # *config targets only - make sure prerequisites are updated, and descend
> diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
> index 509e0856d653..82dd1b65b7a8 100644
> --- a/scripts/Kbuild.include
> +++ b/scripts/Kbuild.include
> @@ -67,86 +67,6 @@ define filechk
> fi
> endef
>
> -######
> -# gcc support functions
> -# See documentation in Documentation/kbuild/makefiles.rst
> -
> -# cc-cross-prefix
> -# Usage: CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-)
> -# Return first <prefix> where a <prefix>gcc is found in PATH.
> -# If no gcc found in PATH with listed prefixes return nothing
> -#
> -# Note: '2>/dev/null' is here to force Make to invoke a shell. Otherwise, it
> -# would try to directly execute the shell builtin 'command'. This workaround
> -# should be kept for a long time since this issue was fixed only after the
> -# GNU Make 4.2.1 release.
> -cc-cross-prefix = $(firstword $(foreach c, $(1), \
> - $(if $(shell command -v -- $(c)gcc 2>/dev/null), $(c))))
> -
> -# output directory for tests below
> -TMPOUT = $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_$$$$
> -
> -# try-run
> -# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise)
> -# Exit code chooses option. "$$TMP" serves as a temporary file and is
> -# automatically cleaned up.
> -try-run = $(shell set -e; \
> - TMP=$(TMPOUT)/tmp; \
> - TMPO=$(TMPOUT)/tmp.o; \
> - mkdir -p $(TMPOUT); \
> - trap "rm -rf $(TMPOUT)" EXIT; \
> - if ($(1)) >/dev/null 2>&1; \
> - then echo "$(2)"; \
> - else echo "$(3)"; \
> - fi)
> -
> -# as-option
> -# Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)
> -
> -as-option = $(call try-run,\
> - $(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2))
> -
> -# as-instr
> -# Usage: cflags-y += $(call as-instr,instr,option1,option2)
> -
> -as-instr = $(call try-run,\
> - printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))
> -
> -# __cc-option
> -# Usage: MY_CFLAGS += $(call __cc-option,$(CC),$(MY_CFLAGS),-march=winchip-c6,-march=i586)
> -__cc-option = $(call try-run,\
> - $(1) -Werror $(2) $(3) -c -x c /dev/null -o "$$TMP",$(3),$(4))
> -
> -# cc-option
> -# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)
> -
> -cc-option = $(call __cc-option, $(CC),\
> - $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS),$(1),$(2))
> -
> -# cc-option-yn
> -# Usage: flag := $(call cc-option-yn,-march=winchip-c6)
> -cc-option-yn = $(call try-run,\
> - $(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)
> -
> -# cc-disable-warning
> -# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
> -cc-disable-warning = $(call try-run,\
> - $(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
> -
> -# cc-ifversion
> -# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
> -cc-ifversion = $(shell [ $(CONFIG_GCC_VERSION)0 $(1) $(2)000 ] && echo $(3) || echo $(4))
> -
> -# ld-option
> -# Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y)
> -ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3))
> -
> -# ld-ifversion
> -# Usage: $(call ld-ifversion, -ge, 22252, y)
> -ld-ifversion = $(shell [ $(CONFIG_LD_VERSION)0 $(1) $(2)0 ] && echo $(3) || echo $(4))
> -
> -######
> -
> ###
> # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
> # Usage:
> diff --git a/scripts/Makefile.build b/scripts/Makefile.build
> index 750d6d5225af..d74d3383666e 100644
> --- a/scripts/Makefile.build
> +++ b/scripts/Makefile.build
> @@ -36,6 +36,7 @@ subdir-ccflags-y :=
> -include include/config/auto.conf
>
> include $(srctree)/scripts/Kbuild.include
> +include $(srctree)/scripts/Makefile.compiler
>
> # The filename Kbuild has precedence over Makefile
> kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
> diff --git a/scripts/Makefile.compiler b/scripts/Makefile.compiler
> new file mode 100644
> index 000000000000..5f759ecc4f04
> --- /dev/null
> +++ b/scripts/Makefile.compiler
> @@ -0,0 +1,77 @@
> +######
> +# gcc support functions
> +# See documentation in Documentation/kbuild/makefiles.rst
> +
> +# cc-cross-prefix
> +# Usage: CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-)
> +# Return first <prefix> where a <prefix>gcc is found in PATH.
> +# If no gcc found in PATH with listed prefixes return nothing
> +#
> +# Note: '2>/dev/null' is here to force Make to invoke a shell. Otherwise, it
> +# would try to directly execute the shell builtin 'command'. This workaround
> +# should be kept for a long time since this issue was fixed only after the
> +# GNU Make 4.2.1 release.
> +cc-cross-prefix = $(firstword $(foreach c, $(1), \
> + $(if $(shell command -v -- $(c)gcc 2>/dev/null), $(c))))
> +
> +# output directory for tests below
> +TMPOUT = $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_$$$$
> +
> +# try-run
> +# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise)
> +# Exit code chooses option. "$$TMP" serves as a temporary file and is
> +# automatically cleaned up.
> +try-run = $(shell set -e; \
> + TMP=$(TMPOUT)/tmp; \
> + TMPO=$(TMPOUT)/tmp.o; \
> + mkdir -p $(TMPOUT); \
> + trap "rm -rf $(TMPOUT)" EXIT; \
> + if ($(1)) >/dev/null 2>&1; \
> + then echo "$(2)"; \
> + else echo "$(3)"; \
> + fi)
> +
> +# as-option
> +# Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)
> +
> +as-option = $(call try-run,\
> + $(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2))
> +
> +# as-instr
> +# Usage: cflags-y += $(call as-instr,instr,option1,option2)
> +
> +as-instr = $(call try-run,\
> + printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))
> +
> +# __cc-option
> +# Usage: MY_CFLAGS += $(call __cc-option,$(CC),$(MY_CFLAGS),-march=winchip-c6,-march=i586)
> +__cc-option = $(call try-run,\
> + $(1) -Werror $(2) $(3) -c -x c /dev/null -o "$$TMP",$(3),$(4))
> +
> +# cc-option
> +# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)
> +
> +cc-option = $(call __cc-option, $(CC),\
> + $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS),$(1),$(2))
> +
> +# cc-option-yn
> +# Usage: flag := $(call cc-option-yn,-march=winchip-c6)
> +cc-option-yn = $(call try-run,\
> + $(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)
> +
> +# cc-disable-warning
> +# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
> +cc-disable-warning = $(call try-run,\
> + $(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
> +
> +# cc-ifversion
> +# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
> +cc-ifversion = $(shell [ $(CONFIG_GCC_VERSION)0 $(1) $(2)000 ] && echo $(3) || echo $(4))
> +
> +# ld-option
> +# Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y)
> +ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3))
> +
> +# ld-ifversion
> +# Usage: $(call ld-ifversion, -ge, 22252, y)
> +ld-ifversion = $(shell [ $(CONFIG_LD_VERSION)0 $(1) $(2)0 ] && echo $(3) || echo $(4))
>
On 13.04.21 14:51, Janosch Frank wrote:
> On 2/28/21 7:10 AM, Masahiro Yamada wrote:
>> scripts/Kbuild.include is included everywhere, but macros such as
>> cc-option are needed by build targets only.
>>
>> For example, when 'make clean' traverses the tree, it does not need
>> to evaluate $(call cc-option,).
>>
>> Split cc-option, ld-option, etc. to scripts/Makefile.compiler, which
>> is only included from the top Makefile and scripts/Makefile.build.
>>
>> Signed-off-by: Masahiro Yamada <[email protected]>
>
> This commit broke the KVM selftest compilation under s390 in linux-next
> for me. Funny enough the compilation is only broken on Ubuntu, under
> Fedora the test fails with an assertion.
>
> FEDORA:
> [root@fedora kvm]# ./set_memory_region_test
> Allowed number of memory slots: 32767
> ==== Test Assertion Failure ====
> lib/kvm_util.c:142: vm->fd >= 0
> pid=1541645 tid=1541645 - Invalid argument
> 1 0x0000000001002f4b: vm_open at kvm_util.c:142
> 2 (inlined by) vm_create at kvm_util.c:258
> 3 0x00000000010015ef: test_add_max_memory_regions at
> set_memory_region_test.c:351
> 4 (inlined by) main at set_memory_region_test.c:397
> 5 0x000003ffa3d2bb89: ?? ??:0
> 6 0x00000000010017ad: .annobin_abi_note.c.hot at crt1.o:?
> KVM_CREATE_VM ioctl failed, rc: -1 errno: 22
>
>
> Ubuntu:
> make[1]: Leaving directory '/mnt/dev/linux'
> gcc -Wall -Wstrict-prototypes -Wuninitialized -O2 -g -std=gnu99
> -fno-stack-protector -fno-PIE -I../../../../tools/include
> -I../../../../tools/arch/s390/include -I../../../../usr/include/
> -Iinclude -Ilib -Iinclude/s390x -I.. -c lib/sparsebit.c -o
> /mnt/dev/linux/tools/testing/selftests/kvm/lib/sparsebit.o
> gcc -Wall -Wstrict-prototypes -Wuninitialized -O2 -g -std=gnu99
> -fno-stack-protector -fno-PIE -I../../../../tools/include
> -I../../../../tools/arch/s390/include -I../../../../usr/include/
> -Iinclude -Ilib -Iinclude/s390x -I.. -c lib/kvm_util.c -o
> /mnt/dev/linux/tools/testing/selftests/kvm/lib/kvm_util.o
> gcc -Wall -Wstrict-prototypes -Wuninitialized -O2 -g -std=gnu99
> -fno-stack-protector -fno-PIE -I../../../../tools/include
> -I../../../../tools/arch/s390/include -I../../../../usr/include/
> -Iinclude -Ilib/s390x -Iinclude/s390x -I.. -c
> lib/s390x/diag318_test_handler.c -o
> /mnt/dev/linux/tools/testing/selftests/kvm/lib/s390x/diag318_test_handler.o
> ar crs /mnt/dev/linux/tools/testing/selftests/kvm/libkvm.a
> /mnt/dev/linux/tools/testing/selftests/kvm/lib/assert.o
> /mnt/dev/linux/tools/testing/selftests/kvm/lib/elf.o
> /mnt/dev/linux/tools/testing/selftests/kvm/lib/io.o
> /mnt/dev/linux/tools/testing/selftests/kvm/lib/kvm_util.o
> /mnt/dev/linux/tools/testing/selftests/kvm/lib/sparsebit.o
> /mnt/dev/linux/tools/testing/selftests/kvm/lib/test_util.o
> /mnt/dev/linux/tools/testing/selftests/kvm/lib/guest_modes.o
> /mnt/dev/linux/tools/testing/selftests/kvm/lib/perf_test_util.o
> /mnt/dev/linux/tools/testing/selftests/kvm/lib/s390x/processor.o
> /mnt/dev/linux/tools/testing/selftests/kvm/lib/s390x/ucall.o
> /mnt/dev/linux/tools/testing/selftests/kvm/lib/s390x/diag318_test_handler.o
> gcc -Wall -Wstrict-prototypes -Wuninitialized -O2 -g -std=gnu99
> -fno-stack-protector -fno-PIE -I../../../../tools/include
> -I../../../../tools/arch/s390/include -I../../../../usr/include/
> -Iinclude -Is390x -Iinclude/s390x -I.. -pthread s390x/memop.c
> /mnt/dev/linux/tools/testing/selftests/kvm/libkvm.a -o
> /mnt/dev/linux/tools/testing/selftests/kvm/s390x/memop
> /usr/bin/ld: /tmp/ccFU8WYF.o: `stdout@@GLIBC_2.2' non-PLT reloc for
> symbol defined in shared library and accessed from executable (rebuild
> file with -fPIC ?)
> /usr/bin/ld: final link failed: bad value
> collect2: error: ld returned 1 exit status
> make: *** [../lib.mk:139:
> /mnt/dev/linux/tools/testing/selftests/kvm/s390x/memop] Error 1
>
It looks like that from tools/testing/selftests/kvm/Makefile
additional linker flags are being ignored with this patch.
no-pie-option := $(call try-run, echo 'int main() { return 0; }' | \
$(CC) -Werror -no-pie -x c - -o "$$TMP", -no-pie)
# On s390, build the testcases KVM-enabled
pgste-option = $(call try-run, echo 'int main() { return 0; }' | \
$(CC) -Werror -Wl$(comma)--s390-pgste -x c - -o "$$TMP",-Wl$(comma)--s390-pgste)
LDFLAGS += -pthread $(no-pie-option) $(pgste-option)
On Tue, Apr 13, 2021 at 10:11 PM Christian Borntraeger
<[email protected]> wrote:
>
>
>
> On 13.04.21 14:51, Janosch Frank wrote:
> > On 2/28/21 7:10 AM, Masahiro Yamada wrote:
> >> scripts/Kbuild.include is included everywhere, but macros such as
> >> cc-option are needed by build targets only.
> >>
> >> For example, when 'make clean' traverses the tree, it does not need
> >> to evaluate $(call cc-option,).
> >>
> >> Split cc-option, ld-option, etc. to scripts/Makefile.compiler, which
> >> is only included from the top Makefile and scripts/Makefile.build.
> >>
> >> Signed-off-by: Masahiro Yamada <[email protected]>
> >
> > This commit broke the KVM selftest compilation under s390 in linux-next
> > for me. Funny enough the compilation is only broken on Ubuntu, under
> > Fedora the test fails with an assertion.
> >
> > FEDORA:
> > [root@fedora kvm]# ./set_memory_region_test
> > Allowed number of memory slots: 32767
> > ==== Test Assertion Failure ====
> > lib/kvm_util.c:142: vm->fd >= 0
> > pid=1541645 tid=1541645 - Invalid argument
> > 1 0x0000000001002f4b: vm_open at kvm_util.c:142
> > 2 (inlined by) vm_create at kvm_util.c:258
> > 3 0x00000000010015ef: test_add_max_memory_regions at
> > set_memory_region_test.c:351
> > 4 (inlined by) main at set_memory_region_test.c:397
> > 5 0x000003ffa3d2bb89: ?? ??:0
> > 6 0x00000000010017ad: .annobin_abi_note.c.hot at crt1.o:?
> > KVM_CREATE_VM ioctl failed, rc: -1 errno: 22
> >
> >
> > Ubuntu:
> > make[1]: Leaving directory '/mnt/dev/linux'
> > gcc -Wall -Wstrict-prototypes -Wuninitialized -O2 -g -std=gnu99
> > -fno-stack-protector -fno-PIE -I../../../../tools/include
> > -I../../../../tools/arch/s390/include -I../../../../usr/include/
> > -Iinclude -Ilib -Iinclude/s390x -I.. -c lib/sparsebit.c -o
> > /mnt/dev/linux/tools/testing/selftests/kvm/lib/sparsebit.o
> > gcc -Wall -Wstrict-prototypes -Wuninitialized -O2 -g -std=gnu99
> > -fno-stack-protector -fno-PIE -I../../../../tools/include
> > -I../../../../tools/arch/s390/include -I../../../../usr/include/
> > -Iinclude -Ilib -Iinclude/s390x -I.. -c lib/kvm_util.c -o
> > /mnt/dev/linux/tools/testing/selftests/kvm/lib/kvm_util.o
> > gcc -Wall -Wstrict-prototypes -Wuninitialized -O2 -g -std=gnu99
> > -fno-stack-protector -fno-PIE -I../../../../tools/include
> > -I../../../../tools/arch/s390/include -I../../../../usr/include/
> > -Iinclude -Ilib/s390x -Iinclude/s390x -I.. -c
> > lib/s390x/diag318_test_handler.c -o
> > /mnt/dev/linux/tools/testing/selftests/kvm/lib/s390x/diag318_test_handler.o
> > ar crs /mnt/dev/linux/tools/testing/selftests/kvm/libkvm.a
> > /mnt/dev/linux/tools/testing/selftests/kvm/lib/assert.o
> > /mnt/dev/linux/tools/testing/selftests/kvm/lib/elf.o
> > /mnt/dev/linux/tools/testing/selftests/kvm/lib/io.o
> > /mnt/dev/linux/tools/testing/selftests/kvm/lib/kvm_util.o
> > /mnt/dev/linux/tools/testing/selftests/kvm/lib/sparsebit.o
> > /mnt/dev/linux/tools/testing/selftests/kvm/lib/test_util.o
> > /mnt/dev/linux/tools/testing/selftests/kvm/lib/guest_modes.o
> > /mnt/dev/linux/tools/testing/selftests/kvm/lib/perf_test_util.o
> > /mnt/dev/linux/tools/testing/selftests/kvm/lib/s390x/processor.o
> > /mnt/dev/linux/tools/testing/selftests/kvm/lib/s390x/ucall.o
> > /mnt/dev/linux/tools/testing/selftests/kvm/lib/s390x/diag318_test_handler.o
> > gcc -Wall -Wstrict-prototypes -Wuninitialized -O2 -g -std=gnu99
> > -fno-stack-protector -fno-PIE -I../../../../tools/include
> > -I../../../../tools/arch/s390/include -I../../../../usr/include/
> > -Iinclude -Is390x -Iinclude/s390x -I.. -pthread s390x/memop.c
> > /mnt/dev/linux/tools/testing/selftests/kvm/libkvm.a -o
> > /mnt/dev/linux/tools/testing/selftests/kvm/s390x/memop
> > /usr/bin/ld: /tmp/ccFU8WYF.o: `stdout@@GLIBC_2.2' non-PLT reloc for
> > symbol defined in shared library and accessed from executable (rebuild
> > file with -fPIC ?)
> > /usr/bin/ld: final link failed: bad value
> > collect2: error: ld returned 1 exit status
> > make: *** [../lib.mk:139:
> > /mnt/dev/linux/tools/testing/selftests/kvm/s390x/memop] Error 1
> >
>
>
>
> It looks like that from tools/testing/selftests/kvm/Makefile
> additional linker flags are being ignored with this patch.
>
> no-pie-option := $(call try-run, echo 'int main() { return 0; }' | \
> $(CC) -Werror -no-pie -x c - -o "$$TMP", -no-pie)
>
> # On s390, build the testcases KVM-enabled
> pgste-option = $(call try-run, echo 'int main() { return 0; }' | \
> $(CC) -Werror -Wl$(comma)--s390-pgste -x c - -o "$$TMP",-Wl$(comma)--s390-pgste)
>
>
> LDFLAGS += -pthread $(no-pie-option) $(pgste-option)
>
Thanks.
I will separate Kbuild and the tool build system.
https://patchwork.kernel.org/project/linux-kbuild/patch/[email protected]/
I do not want to be bothered by the can of worms.
--
Best Regards
Masahiro Yamada