Hi folks Here is a follow-up for this issue https://github.com/Open-CAS/open-cas-linux/issues/540 opencas project builds an out-of-tree kernel module and uses system-level kernel header. In my case these headers are installed to /lib/modules/5.9.1-arch1-1/build So if I do $ cd /lib/modules/5.9.1-arch1-1/build $ make kernelversion I get following output: mkdir: cannot create directory ‘.tmp_86541’: Permission denied mkdir: cannot create directory ‘.tmp_86543’: Permission denied mkdir: cannot create directory ‘.tmp_86545’: Permission denied mkdir: cannot create directory ‘.tmp_86547’: Permission denied ....... mkdir: cannot create directory ‘.tmp_86626’: Permission denied mkdir: cannot create directory ‘.tmp_86628’: Permission denied mkdir: cannot create directory ‘.tmp_86630’: Permission denied 5.9.1-arch1 Quick debugging shows that it comes from scripts/Kbuild.include following lines in particular: # 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) TMPOUT points to headers directory and in my case it is a part of /usr partition that restricts user writes. TMPOUT should avoid writing to headers dir and use `mktemp` instead.
