(I removed UMMODE_LIB vs !MMU part, but leave replies to the others) On Thu, 08 Oct 2020 04:20:00 +0900, Johannes Berg wrote: > > make defconfig ARCH=um UMMODE=library > > make ARCH=um UMMODE=library > > Why not make it a real Kconfig symbol? I find the ARCH=um tricky enough > to remember all the time, so much I usually write a "GNUmakefile" with > > export ARCH=um > include Makefile > > :-) > > > +config UMMODE_LIB > > + bool "UML mode: library mode" > > + default y if "$(UMMODE)" = "library" > > So wait, you _can_ switch that through Kconfig then, because you made it > a visible option (string after "bool"). But it won't work, because then > you later in the build system etc. still check UMMODE instead of > CONFIG_UMMODE_LIB. Seems like something that ought to be fixed one way > or the other - at the very least hide this symbol if setting it manually > is invalid. I now see what I went wrong.. thanks, will fix this with your suggestion not to use the command line argument. > > + help > > + This mode switches a mode to build a library of UML (Linux > > + Kernel Library/LKL). This switch is exclusive to "kernel mode" > > + of UML, which is traditional mode of UML. > > Not sure if that historically made more sense, but you don't have any > UMMODE_KERNEL option or something like that, so the help text seems > confusing? thanks, we will clarify this text. > > +ifeq ($(UMMODE),library) > > + SUBARCH := um/nommu > > +endif > > > INSTALL_PATH=$(objtree)/tools/um > > +ifeq ($(UMMODE),library) > > Here a few places using UMMODE which must come from the command line. will fix this too. > > linux.o: vmlinux > > @echo ' LINK $@' > > - $(Q)$(OBJCOPY) -R .eh_frame $< $@ > > + $(Q)$(OBJCOPY) -R .eh_frame -L sem_init -L sem_post -L sem_wait -L sem_destroy $< $@ > > Care to explain? If we will link a userspace binary with liblinux.a (LKL) and libpthread, the the symbols sem_init, etc will conflict with the one in the kernel (ipc/sem.c). objcopy command with -L localizes the symbol specified to avoid this conflict. We will add the description as a comment. > > + select UACCESS_MEMCPY > > + select ARCH_THREAD_STACK_ALLOCATOR > > + select ARCH_HAS_SYSCALL_WRAPPER > > You never use this except for the selects, maybe can go elsewhere? This is used at the patch 12/21, so add Kconfig earlier and move this to 12/21 would be better. We'll work on. > > +config 64BIT > > + bool > > + default y > > + > > +config GENERIC_CSUM > > + def_bool y > > + > > +config GENERIC_ATOMIC64 > > + bool > > + default y if !64BIT > > + > > +config SECCOMP > > + bool > > + default n > > + > > +config GENERIC_HWEIGHT > > + def_bool y > > + > > +config GENERIC_CALIBRATE_DELAY > > + bool > > + default n > > + > > +config STACKTRACE_SUPPORT > > + bool > > + default n > > You ... were just changing these elsewhere, so one of that isn't needed? you're right too. will fix it. -- Hajime
