From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from todd.t-8ch.de (todd.t-8ch.de [159.69.126.157]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D9F4A2DE710; Thu, 25 Sep 2025 16:36:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.69.126.157 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758818202; cv=none; b=CRyAZQbNMRZXvkECdAy5KhxoAEFBNkNxs2QAqrliWECjGlwQeW3FlS0bgvwAmWrbeDAV88fWz3hr6Odt2xCV21GmH8HzSpFV7qQ7cpuQ6OSgaXZ2uHlSsAQ+PjSekgz8waLoupl/37yi6okGwBEJtdJ+Wr+7O56+6TqR174H5io= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758818202; c=relaxed/simple; bh=X4SLgLUDA6ZIyS057+iCcCJ7hLdHj/NTyAmnioiy+M4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ttcM+ZK2RyOjk8rtME21kSkZXZgNk3o13ffu0P+ml0R4ep9XC1skOSdIPOJiXKpJ1YA8JgQvTiYiZ+5HGtiPBtOyx0xgEqH28CWjiF7OEgaUm4IBuxjKKXTvHtZ0ZwoX77e2BxN9WIc6CCkCeffcE3TA/Q+6N7Ecvg1xHSikyAY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=weissschuh.net; spf=pass smtp.mailfrom=weissschuh.net; dkim=pass (1024-bit key) header.d=weissschuh.net header.i=@weissschuh.net header.b=TNNGcmYA; arc=none smtp.client-ip=159.69.126.157 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=weissschuh.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=weissschuh.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=weissschuh.net header.i=@weissschuh.net header.b="TNNGcmYA" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=weissschuh.net; s=mail; t=1758818198; bh=X4SLgLUDA6ZIyS057+iCcCJ7hLdHj/NTyAmnioiy+M4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=TNNGcmYApRO0f5DE3mdIWcAap4G5OZH5QAW1crAKc/89M+09k74DP/7CDM6RSBwTv PE/Ry6Qty4WYk9+QabThhZldMiPwLrO8BNt56Fd5NDMhidm+tYiPQofMvQezTTKErT ZN9hvBfiqOMZOS6/zGuvB2bFeAuR1sxNKULAQpyI= Date: Thu, 25 Sep 2025 18:36:36 +0200 From: Thomas =?utf-8?Q?Wei=C3=9Fschuh?= To: Benjamin Berg Cc: linux-um@lists.infradead.org, Willy Tarreau , linux-kselftest@vger.kernel.org, Arnaldo Carvalho de Melo , linux-kernel@vger.kernel.org, Benjamin Berg Subject: Re: [PATCH v3 08/12] um: add infrastructure to build files using nolibc Message-ID: <43a71f2c-2d3d-4b66-b755-d182eefc90d2@t-8ch.de> References: <20250924142059.527768-1-benjamin@sipsolutions.net> <20250924142059.527768-9-benjamin@sipsolutions.net> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250924142059.527768-9-benjamin@sipsolutions.net> On 2025-09-24 16:20:55+0200, Benjamin Berg wrote: > From: Benjamin Berg > > Add NOLIBC_CFLAGS and NOLIBC_OBJS to build files against nolibc rather > than libc. With this it is possible to move to nolibc in smaller steps. > > Set NOLIBC_IGNORE_ERRNO, as the nolibc errno implementation is overly > simple and cannot handle threading. nolibc provides sys_* functions that > do not emulate the libc errno behaviour and can be used instead. > > Leave the syscall definition for kernel code for now, but guard it as it > is a macro in nolibc. > > Signed-off-by: Benjamin Berg > > --- > v3: > - Change the syscall guard to use __KERNEL__ > > v2: > - Do not include nolibc.h via CFLAGS > - Make syscall guard more explicit > - Remove __UM_NOLIBC__ define, it is not needed > - Fix out-of-tree building > --- > arch/um/Makefile | 20 +++++++++++++++++++- > arch/um/include/shared/os.h | 2 ++ > arch/um/include/shared/user.h | 1 - > arch/um/scripts/Makefile.rules | 8 +++++++- > 4 files changed, 28 insertions(+), 3 deletions(-) > > diff --git a/arch/um/Makefile b/arch/um/Makefile > index f7c509262568..c3a81df50911 100644 > --- a/arch/um/Makefile > +++ b/arch/um/Makefile > @@ -78,6 +78,24 @@ USER_CFLAGS = $(patsubst $(KERNEL_DEFINES),,$(patsubst -I%,,$(KBUILD_CFLAGS))) \ > -include $(srctree)/include/linux/kern_levels.h \ > -include $(srctree)/$(ARCH_DIR)/include/shared/user.h > > +NOLIBC_CFLAGS = $(patsubst $(KERNEL_DEFINES),,$(patsubst -I%,,$(KBUILD_CFLAGS))) \ > + $(ARCH_INCLUDE) $(MODE_INCLUDE) $(filter -I%,$(CFLAGS)) \ > + -I $(srctree)/tools/include \ > + -D__EXPORTED_HEADERS__ \ > + -D__UM_HOST__ \ > + -DNOLIBC_NO_RUNTIME \ > + -DNOLIBC_IGNORE_ERRNO \ > + -nostdlib -nostdinc -static \ > + -I$(srctree)/include/uapi \ > + -I$(srctree)/$(HOST_DIR)/include/uapi \ > + -I$(objtree)/$(HOST_DIR)/include/generated/uapi \ > + -I $(srctree)/tools/include/nolibc \ > + -I $(srctree)/usr/include \ This looks incorrect. The UAPI headers would be installed to $(objtree). But UML does not even use CONFIG_HEADERS_INSTALL. Also the whitespace is inconsistent between different lines. > + -include $(objtree)/include/generated/autoconf.h \ > + -include $(srctree)/tools/include/linux/kconfig.h \ > + -include $(srctree)/include/linux/kern_levels.h \ > + -include $(srctree)/$(ARCH_DIR)/include/shared/user.h > + > #This will adjust *FLAGS accordingly to the platform. > include $(srctree)/$(ARCH_DIR)/Makefile-os-Linux > > @@ -160,4 +178,4 @@ archclean: > -o -name '*.gcov' \) -type f -print | xargs rm -f > $(Q)$(MAKE) -f $(srctree)/Makefile ARCH=$(HEADER_ARCH) clean > > -export HEADER_ARCH SUBARCH USER_CFLAGS CFLAGS_NO_HARDENING DEV_NULL_PATH > +export HEADER_ARCH SUBARCH USER_CFLAGS NOLIBC_CFLAGS CFLAGS_NO_HARDENING DEV_NULL_PATH (...)