From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 857922DB788 for ; Fri, 2 Oct 2026 00:51:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790902313; cv=none; b=mRJk+hIO73zJlTFwQYPKlKcLmDujxrVNoyi5bF8T4RlJtHJZER70lyttlZQoQcjKEcgpZogXfuh3kPIa6egSHAwcuxUnqC58zWGEHyzsraRhbjSjkDQlBYOdopI6f9hxIM5yozYpRtnQ8ctYrPGgPsB/arWYX6lq+IstesqciPg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790902313; c=relaxed/simple; bh=rI4akYqSTTVRRAVSN7osfzuJcm2snp5zraNiNKXzmRY=; h=Date:To:From:Subject:Message-Id; b=PdlNCZ0t8MQlu6FXU2zKZl2OfU4w4PqzCbXrgFC0cuiTsC6MNfCmBHMdcnFSU0SW2HncP3g9Wl9rBsrRp3H3iAyngmMk/7j/+d0QZzWMIi50bMtwRx2g/LJ9aZkzk8HZ2hh3zBFyH0QeSj/V4mjAHhC44nMgHF8Ngj5Bq1yb+n4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=kj/PrBlj; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="kj/PrBlj" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 082281F00893; Fri, 2 Oct 2026 00:51:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1790902312; bh=OIforvvvAwxOU8ToK8975Im6KjjoKIm7cs0VBLUqMQw=; h=Date:To:From:Subject; b=kj/PrBljy3U7T8Tyfun2LKkVLFHQgyijRjV42OmV3gI+xz91Jl1npg51KaRCQ3Iqm dibGsJSFfVWu4VyTOHDbwvDNVizRR6KJYcgOwMUAFx6gtNs6e0bH4EPEbtXCW3DB6v vxjeH5uGctWPVwxuZCNXCM8lbqoh/epQkGPYRnkc= Date: Thu, 01 Oct 2026 17:51:51 -0700 To: mm-commits@vger.kernel.org,zaslonko@linux.ibm.com,oberpar@linux.ibm.com,nsc@kernel.org,nathan@kernel.org,masahiroy@kernel.org,arnd@arndb.de,khorenko@virtuozzo.com,akpm@linux-foundation.org From: Andrew Morton Subject: + kbuild-move-gcov-flags-to-scripts-makefilegcov.patch added to mm-nonmm-unstable branch Message-Id: <20261002005152.082281F00893@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: kbuild: move GCOV flags to scripts/Makefile.gcov has been added to the -mm mm-nonmm-unstable branch. Its filename is kbuild-move-gcov-flags-to-scripts-makefilegcov.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kbuild-move-gcov-flags-to-scripts-makefilegcov.patch This patch will later appear in the mm-nonmm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via various branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there most days ------------------------------------------------------ From: Konstantin Khorenko Subject: kbuild: move GCOV flags to scripts/Makefile.gcov Date: Thu, 01 Oct 2026 18:57:12 +0200 * split the CFLAGS_GCOV block out of the top-level Makefile into scripts/Makefile.gcov * include it via include-$(CONFIG_GCOV_KERNEL) like neighbour KASAN/KCOV/UBSAN makefiles do * keep the include before scripts/Makefile.gcc-plugins: the try-run must not get -fplugin= options, plugins do not exist on clean builds CFLAGS_GCOV is no longer defined when CONFIG_GCOV_KERNEL is off: * its user in scripts/Makefile.lib is guarded by the CONFIG_GCOV_KERNEL * in i915/xe header an empty value is harmless The try-run compiler invocations also stop running on builds without GCOV. Link: https://lore.kernel.org/20261001-b4-prep-gcov-v1-2-794792e06f24@virtuozzo.com Signed-off-by: Konstantin Khorenko Signed-off-by: Andrew Morton Suggested-by: Peter Oberparleiter Cc: Nathan Chancellor Cc: Nicolas Schier Cc: Masahiro Yamada Cc: Arnd Bergmann Cc: Mikhail Zaslonko --- MAINTAINERS | 1 + Makefile | 22 +--------------------- scripts/Makefile.gcov | 21 +++++++++++++++++++++ 3 files changed, 23 insertions(+), 21 deletions(-) --- a/MAINTAINERS~kbuild-move-gcov-flags-to-scripts-makefilegcov +++ a/MAINTAINERS @@ -10898,6 +10898,7 @@ M: Peter Oberparleiter --- a/Makefile~kbuild-move-gcov-flags-to-scripts-makefilegcov +++ a/Makefile @@ -1176,27 +1176,6 @@ endif # Ensure compilers do not transform certain loops into calls to wcslen() KBUILD_CFLAGS += -fno-builtin-wcslen -CFLAGS_GCOV := -fprofile-arcs -ftest-coverage -ifdef CONFIG_CC_IS_GCC -CFLAGS_GCOV += -fno-tree-loop-im -# Use atomic counter updates to avoid concurrent-access crashes in GCOV. -# Only enable if -fprofile-update=prefer-atomic does not introduce new -# undefined symbols (e.g. libatomic calls that the kernel cannot link). -CFLAGS_GCOV += $(call try-run,\ - echo 'long long x; void f(void){x++;}' | \ - $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -w $(CFLAGS_GCOV) \ - -x c - -c -o "$$TMP.base" && \ - echo 'long long x; void f(void){x++;}' | \ - $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -w $(CFLAGS_GCOV) \ - -fprofile-update=prefer-atomic \ - -x c - -c -o "$$TMP" && \ - $(NM) "$$TMP.base" | grep ' U ' > "$$TMP.ubase" || true ; \ - $(NM) "$$TMP" | grep ' U ' > "$$TMP.utest" || true ; \ - cmp -s "$$TMP.ubase" "$$TMP.utest",\ - -fprofile-update=prefer-atomic) -endif -export CFLAGS_GCOV - # change __FILE__ to the relative path to the source directory ifdef building_out_of_srctree KBUILD_CPPFLAGS += -fmacro-prefix-map=$(srcroot)/= @@ -1214,6 +1193,7 @@ include-$(CONFIG_KCSAN) += scripts/Make include-$(CONFIG_KMSAN) += scripts/Makefile.kmsan include-$(CONFIG_UBSAN) += scripts/Makefile.ubsan include-$(CONFIG_KCOV) += scripts/Makefile.kcov +include-$(CONFIG_GCOV_KERNEL) += scripts/Makefile.gcov include-$(CONFIG_RANDSTRUCT) += scripts/Makefile.randstruct include-$(CONFIG_KSTACK_ERASE) += scripts/Makefile.kstack_erase include-$(CONFIG_AUTOFDO_CLANG) += scripts/Makefile.autofdo diff --git a/scripts/Makefile.gcov a/scripts/Makefile.gcov new file mode 100644 --- /dev/null +++ a/scripts/Makefile.gcov @@ -0,0 +1,21 @@ +# SPDX-License-Identifier: GPL-2.0-only +CFLAGS_GCOV := -fprofile-arcs -ftest-coverage +ifdef CONFIG_CC_IS_GCC +CFLAGS_GCOV += -fno-tree-loop-im +# Use atomic counter updates to avoid concurrent-access crashes in GCOV. +# Only enable if -fprofile-update=prefer-atomic does not introduce new +# undefined symbols (e.g. libatomic calls that the kernel cannot link). +CFLAGS_GCOV += $(call try-run,\ + echo 'long long x; void f(void){x++;}' | \ + $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -w $(CFLAGS_GCOV) \ + -x c - -c -o "$$TMP.base" && \ + echo 'long long x; void f(void){x++;}' | \ + $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -w $(CFLAGS_GCOV) \ + -fprofile-update=prefer-atomic \ + -x c - -c -o "$$TMP" && \ + $(NM) "$$TMP.base" | grep ' U ' > "$$TMP.ubase" || true ; \ + $(NM) "$$TMP" | grep ' U ' > "$$TMP.utest" || true ; \ + cmp -s "$$TMP.ubase" "$$TMP.utest",\ + -fprofile-update=prefer-atomic) +endif +export CFLAGS_GCOV _ Patches currently in -mm which might be from khorenko@virtuozzo.com are selftests-core-fix-unshare_test-with-large-fsnr_open.patch kbuild-use-cflags_gcov-in-the-prefer-atomic-try-run-test.patch kbuild-move-gcov-flags-to-scripts-makefilegcov.patch