6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Masahiro Yamada <masahiroy@xxxxxxxxxx> [ Upstream commit d1d0963121769d8d16150b913fe886e48efefa51 ] When CONFIG_OBJTOOL=y or CONFIG_DEBUG_INFO_BTF=y, parallel builds show awkward "mkdir -p ..." logs. $ make -j16 [ snip ] mkdir -p /home/masahiro/ref/linux/tools/objtool && make O=/home/masahiro/ref/linux subdir=tools/objtool --no-print-directory -C objtool mkdir -p /home/masahiro/ref/linux/tools/bpf/resolve_btfids && make O=/home/masahiro/ref/linux subdir=tools/bpf/resolve_btfids --no-print-directory -C bpf/resolve_btfids Defining MAKEFLAGS=<value> on the command line wipes out command line switches from the resultant MAKEFLAGS definition, even though the command line switches are active. [1] MAKEFLAGS puts all single-letter options into the first word, and that word will be empty if no single-letter options were given. [2] However, this breaks if MAKEFLAGS=<value> is given on the command line. The tools/ and tools/% targets set MAKEFLAGS=<value> on the command line, which breaks the following code in tools/scripts/Makefile.include: short-opts := $(firstword -$(MAKEFLAGS)) If MAKEFLAGS really needs modification, it should be done through the environment variable, as follows: MAKEFLAGS=<value> $(MAKE) ... That said, I question whether modifying MAKEFLAGS is necessary here. The only flag we might want to exclude is --no-print-directory, as the tools build system changes the working directory. However, people might find the "Entering/Leaving directory" logs annoying. I simply removed the offending MAKEFLAGS=<value>. [1]: https://savannah.gnu.org/bugs/?62469 [2]: https://www.gnu.org/software/make/manual/make.html#Testing-Flags Fixes: ea01fa9f63ae ("tools: Connect to the kernel build system") Fixes: a50e43332756 ("perf tools: Honor parallel jobs") Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx> Tested-by: Daniel Xu <dxu@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- Makefile | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/Makefile b/Makefile index 1d777c3eb7fb9..cbd091c511d82 100644 --- a/Makefile +++ b/Makefile @@ -1348,18 +1348,13 @@ ifneq ($(wildcard $(resolve_btfids_O)),) $(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean endif -# Clear a bunch of variables before executing the submake -ifeq ($(quiet),silent_) -tools_silent=s -endif - tools/: FORCE $(Q)mkdir -p $(objtree)/tools - $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ + $(Q)$(MAKE) LDFLAGS= O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ tools/%: FORCE $(Q)mkdir -p $(objtree)/tools - $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $* + $(Q)$(MAKE) LDFLAGS= O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $* # --------------------------------------------------------------------------- # Kernel selftest -- 2.39.5