From 0f7636e1654338c34e3c220c02b2ffad78b6ccc0 Mon Sep 17 00:00:00 2001 From: Paul Menzel Date: Tue, 11 Aug 2020 11:29:23 +0200 Subject: init/Kconfig: Fix CPU number in LOG_CPU_MAX_BUF_SHIFT description Currently, LOG_BUF_SHIFT defaults to 17, which is 2 ^ 17 bytes = 128 KB, and LOG_CPU_MAX_BUF_SHIFT defaults to 12, which is 2 ^ 12 bytes = 4 KB. Half of 128 KB is 64 KB, so more than 16 CPUs are required for the value to be used, as then the sum of contributions is greater than 64 KB for the first time. My guess is, that the description was written with the configuration values used in the SUSE in mind. Fixes: 23b2899f7f194f06e ("printk: allow increasing the ring buffer depending on the number of CPUs") Cc: Luis R. Rodriguez Cc: linux-kernel@vger.kernel.org Signed-off-by: Paul Menzel Reviewed-by: Petr Mladek Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20200811092924.6256-1-pmenzel@molgen.mpg.de --- init/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'init') diff --git a/init/Kconfig b/init/Kconfig index c9446911cf41..02d13ae27abb 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -719,7 +719,7 @@ config LOG_CPU_MAX_BUF_SHIFT with more CPUs. Therefore this value is used only when the sum of contributions is greater than the half of the default kernel ring buffer as defined by LOG_BUF_SHIFT. The default values are set - so that more than 64 CPUs are needed to trigger the allocation. + so that more than 16 CPUs are needed to trigger the allocation. Also this option is ignored when "log_buf_len" kernel parameter is used as it forces an exact (power of two) size of the ring buffer. -- cgit v1.2.3 From 24aed09451270b6a2a78adf8a34918d12ffb7dcf Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Fri, 20 Nov 2020 11:29:04 +0900 Subject: bootconfig: Load size and checksum in the footer as le32 Load the size and the checksum fields in the footer as le32 instead of u32. This will allow us to apply bootconfig to the cross build initrd without caring the endianness. Link: https://lkml.kernel.org/r/160583934457.547349.10504070298990791074.stgit@devnote2 Reported-by: Steven Rostedt Suggested-by: Linus Torvalds Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) --- init/main.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'init') diff --git a/init/main.c b/init/main.c index 20baced721ad..32b2a8affafd 100644 --- a/init/main.c +++ b/init/main.c @@ -288,8 +288,8 @@ static void * __init get_boot_config_from_initrd(u32 *_size, u32 *_csum) found: hdr = (u32 *)(data - 8); - size = hdr[0]; - csum = hdr[1]; + size = le32_to_cpu(hdr[0]); + csum = le32_to_cpu(hdr[1]); data = ((void *)hdr) - size; if ((unsigned long)data < initrd_start) { -- cgit v1.2.3 From 59612b24f78a0b61fe078ec9dff2e48e9cec52c0 Mon Sep 17 00:00:00 2001 From: Nathan Chancellor Date: Thu, 19 Nov 2020 13:46:56 -0700 Subject: kbuild: Hoist '--orphan-handling' into Kconfig Currently, '--orphan-handling=warn' is spread out across four different architectures in their respective Makefiles, which makes it a little unruly to deal with in case it needs to be disabled for a specific linker version (in this case, ld.lld 10.0.1). To make it easier to control this, hoist this warning into Kconfig and the main Makefile so that disabling it is simpler, as the warning will only be enabled in a couple places (main Makefile and a couple of compressed boot folders that blow away LDFLAGS_vmlinx) and making it conditional is easier due to Kconfig syntax. One small additional benefit of this is saving a call to ld-option on incremental builds because we will have already evaluated it for CONFIG_LD_ORPHAN_WARN. To keep the list of supported architectures the same, introduce CONFIG_ARCH_WANT_LD_ORPHAN_WARN, which an architecture can select to gain this automatically after all of the sections are specified and size asserted. A special thanks to Kees Cook for the help text on this config. Link: https://github.com/ClangBuiltLinux/linux/issues/1187 Acked-by: Kees Cook Acked-by: Michael Ellerman (powerpc) Reviewed-by: Nick Desaulniers Tested-by: Nick Desaulniers Signed-off-by: Nathan Chancellor Signed-off-by: Masahiro Yamada --- Makefile | 6 ++++++ arch/Kconfig | 9 +++++++++ arch/arm/Kconfig | 1 + arch/arm/Makefile | 4 ---- arch/arm/boot/compressed/Makefile | 4 +++- arch/arm64/Kconfig | 1 + arch/arm64/Makefile | 4 ---- arch/powerpc/Kconfig | 1 + arch/powerpc/Makefile | 1 - arch/x86/Kconfig | 1 + arch/x86/Makefile | 3 --- arch/x86/boot/compressed/Makefile | 4 +++- init/Kconfig | 5 +++++ 13 files changed, 30 insertions(+), 14 deletions(-) (limited to 'init') diff --git a/Makefile b/Makefile index ae1592c1f5d6..8327725e5d76 100644 --- a/Makefile +++ b/Makefile @@ -986,6 +986,12 @@ ifeq ($(CONFIG_RELR),y) LDFLAGS_vmlinux += --pack-dyn-relocs=relr endif +# We never want expected sections to be placed heuristically by the +# linker. All sections should be explicitly named in the linker script. +ifdef CONFIG_LD_ORPHAN_WARN +LDFLAGS_vmlinux += --orphan-handling=warn +endif + # Align the bit size of userspace programs with the kernel KBUILD_USERCFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS)) KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS)) diff --git a/arch/Kconfig b/arch/Kconfig index 56b6ccc0e32d..ba4e966484ab 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -1028,6 +1028,15 @@ config HAVE_STATIC_CALL_INLINE bool depends on HAVE_STATIC_CALL +config ARCH_WANT_LD_ORPHAN_WARN + bool + help + An arch should select this symbol once all linker sections are explicitly + included, size-asserted, or discarded in the linker scripts. This is + important because we never want expected sections to be placed heuristically + by the linker, since the locations of such sections can change between linker + versions. + source "kernel/gcov/Kconfig" source "scripts/gcc-plugins/Kconfig" diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index fe2f17eb2b50..002e0cf025f5 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -35,6 +35,7 @@ config ARM select ARCH_USE_CMPXCHG_LOCKREF select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU select ARCH_WANT_IPC_PARSE_VERSION + select ARCH_WANT_LD_ORPHAN_WARN select BINFMT_FLAT_ARGVP_ENVP_ON_STACK select BUILDTIME_TABLE_SORT if MMU select CLONE_BACKWARDS diff --git a/arch/arm/Makefile b/arch/arm/Makefile index 4d76eab2b22d..e15f76ca2887 100644 --- a/arch/arm/Makefile +++ b/arch/arm/Makefile @@ -16,10 +16,6 @@ LDFLAGS_vmlinux += --be8 KBUILD_LDFLAGS_MODULE += --be8 endif -# We never want expected sections to be placed heuristically by the -# linker. All sections should be explicitly named in the linker script. -LDFLAGS_vmlinux += $(call ld-option, --orphan-handling=warn) - GZFLAGS :=-9 #KBUILD_CFLAGS +=-pipe diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile index 47f001ca5499..e1567418a2b1 100644 --- a/arch/arm/boot/compressed/Makefile +++ b/arch/arm/boot/compressed/Makefile @@ -129,7 +129,9 @@ LDFLAGS_vmlinux += --no-undefined # Delete all temporary local symbols LDFLAGS_vmlinux += -X # Report orphan sections -LDFLAGS_vmlinux += $(call ld-option, --orphan-handling=warn) +ifdef CONFIG_LD_ORPHAN_WARN +LDFLAGS_vmlinux += --orphan-handling=warn +endif # Next argument is a linker script LDFLAGS_vmlinux += -T diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 1515f6f153a0..a6b5b7ef40ae 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -81,6 +81,7 @@ config ARM64 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT select ARCH_WANT_FRAME_POINTERS select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36) + select ARCH_WANT_LD_ORPHAN_WARN select ARCH_HAS_UBSAN_SANITIZE_ALL select ARM_AMBA select ARM_ARCH_TIMER diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile index 5789c2d18d43..6a87d592bd00 100644 --- a/arch/arm64/Makefile +++ b/arch/arm64/Makefile @@ -28,10 +28,6 @@ LDFLAGS_vmlinux += --fix-cortex-a53-843419 endif endif -# We never want expected sections to be placed heuristically by the -# linker. All sections should be explicitly named in the linker script. -LDFLAGS_vmlinux += $(call ld-option, --orphan-handling=warn) - ifeq ($(CONFIG_ARM64_USE_LSE_ATOMICS), y) ifneq ($(CONFIG_ARM64_LSE_ATOMICS), y) $(warning LSE atomics not supported by binutils) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index e9f13fe08492..5181872f9452 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -152,6 +152,7 @@ config PPC select ARCH_USE_QUEUED_SPINLOCKS if PPC_QUEUED_SPINLOCKS select ARCH_WANT_IPC_PARSE_VERSION select ARCH_WANT_IRQS_OFF_ACTIVATE_MM + select ARCH_WANT_LD_ORPHAN_WARN select ARCH_WEAK_RELEASE_ACQUIRE select BINFMT_ELF select BUILDTIME_TABLE_SORT diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile index a4d56f0a41d9..d9eb0da845e1 100644 --- a/arch/powerpc/Makefile +++ b/arch/powerpc/Makefile @@ -123,7 +123,6 @@ endif LDFLAGS_vmlinux-y := -Bstatic LDFLAGS_vmlinux-$(CONFIG_RELOCATABLE) := -pie LDFLAGS_vmlinux := $(LDFLAGS_vmlinux-y) -LDFLAGS_vmlinux += $(call ld-option,--orphan-handling=warn) ifdef CONFIG_PPC64 ifeq ($(call cc-option-yn,-mcmodel=medium),y) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index f6946b81f74a..fbf26e0f7a6a 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -100,6 +100,7 @@ config X86 select ARCH_WANT_DEFAULT_BPF_JIT if X86_64 select ARCH_WANTS_DYNAMIC_TASK_STRUCT select ARCH_WANT_HUGE_PMD_SHARE + select ARCH_WANT_LD_ORPHAN_WARN select ARCH_WANTS_THP_SWAP if X86_64 select BUILDTIME_TABLE_SORT select CLKEVT_I8253 diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 154259f18b8b..1bf21746f4ce 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -209,9 +209,6 @@ ifdef CONFIG_X86_64 LDFLAGS_vmlinux += -z max-page-size=0x200000 endif -# We never want expected sections to be placed heuristically by the -# linker. All sections should be explicitly named in the linker script. -LDFLAGS_vmlinux += $(call ld-option, --orphan-handling=warn) archscripts: scripts_basic $(Q)$(MAKE) $(build)=arch/x86/tools relocs diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index ee249088cbfe..40b8fd375d52 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -61,7 +61,9 @@ KBUILD_LDFLAGS += $(call ld-option,--no-ld-generated-unwind-info) # Compressed kernel should be built as PIE since it may be loaded at any # address by the bootloader. LDFLAGS_vmlinux := -pie $(call ld-option, --no-dynamic-linker) -LDFLAGS_vmlinux += $(call ld-option, --orphan-handling=warn) +ifdef CONFIG_LD_ORPHAN_WARN +LDFLAGS_vmlinux += --orphan-handling=warn +endif LDFLAGS_vmlinux += -T hostprogs := mkpiggy diff --git a/init/Kconfig b/init/Kconfig index c9446911cf41..92c58b45abb8 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1348,6 +1348,11 @@ config LD_DEAD_CODE_DATA_ELIMINATION present. This option is not well tested yet, so use at your own risk. +config LD_ORPHAN_WARN + def_bool y + depends on ARCH_WANT_LD_ORPHAN_WARN + depends on $(ld-option,--orphan-handling=warn) + config SYSCTL bool -- cgit v1.2.3 From d5750cd3c5486e9c0fa11100df01de8ca0c13fa7 Mon Sep 17 00:00:00 2001 From: Nathan Chancellor Date: Thu, 19 Nov 2020 13:46:58 -0700 Subject: kbuild: Disable CONFIG_LD_ORPHAN_WARN for ld.lld 10.0.1 ld.lld 10.0.1 spews a bunch of various warnings about .rela sections, along with a few others. Newer versions of ld.lld do not have these warnings. As a result, do not add '--orphan-handling=warn' to LDFLAGS_vmlinux if ld.lld's version is not new enough. Link: https://github.com/ClangBuiltLinux/linux/issues/1187 Link: https://github.com/ClangBuiltLinux/linux/issues/1193 Reported-by: Arvind Sankar Reported-by: kernelci.org bot Reported-by: Mark Brown Reviewed-by: Kees Cook Signed-off-by: Nathan Chancellor Reviewed-by: Nick Desaulniers Signed-off-by: Masahiro Yamada --- MAINTAINERS | 1 + init/Kconfig | 5 +++++ scripts/lld-version.sh | 20 ++++++++++++++++++++ 3 files changed, 26 insertions(+) create mode 100755 scripts/lld-version.sh (limited to 'init') diff --git a/MAINTAINERS b/MAINTAINERS index a008b70f3c16..286ed8e6b924 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -4274,6 +4274,7 @@ B: https://github.com/ClangBuiltLinux/linux/issues C: irc://chat.freenode.net/clangbuiltlinux F: Documentation/kbuild/llvm.rst F: scripts/clang-tools/ +F: scripts/lld-version.sh K: \b(?i:clang|llvm)\b CLEANCACHE API diff --git a/init/Kconfig b/init/Kconfig index 92c58b45abb8..b9037d6c5ab3 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -47,6 +47,10 @@ config CLANG_VERSION int default $(shell,$(srctree)/scripts/clang-version.sh $(CC)) +config LLD_VERSION + int + default $(shell,$(srctree)/scripts/lld-version.sh $(LD)) + config CC_CAN_LINK bool default $(success,$(srctree)/scripts/cc-can-link.sh $(CC) $(CLANG_FLAGS) $(m64-flag)) if 64BIT @@ -1351,6 +1355,7 @@ config LD_DEAD_CODE_DATA_ELIMINATION config LD_ORPHAN_WARN def_bool y depends on ARCH_WANT_LD_ORPHAN_WARN + depends on !LD_IS_LLD || LLD_VERSION >= 110000 depends on $(ld-option,--orphan-handling=warn) config SYSCTL diff --git a/scripts/lld-version.sh b/scripts/lld-version.sh new file mode 100755 index 000000000000..d70edb4d8a4f --- /dev/null +++ b/scripts/lld-version.sh @@ -0,0 +1,20 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# +# Usage: $ ./scripts/lld-version.sh ld.lld +# +# Print the linker version of `ld.lld' in a 5 or 6-digit form +# such as `100001' for ld.lld 10.0.1 etc. + +linker_string="$($* --version)" + +if ! ( echo $linker_string | grep -q LLD ); then + echo 0 + exit 1 +fi + +VERSION=$(echo $linker_string | cut -d ' ' -f 2) +MAJOR=$(echo $VERSION | cut -d . -f 1) +MINOR=$(echo $VERSION | cut -d . -f 2) +PATCHLEVEL=$(echo $VERSION | cut -d . -f 3) +printf "%d%02d%02d\\n" $MAJOR $MINOR $PATCHLEVEL -- cgit v1.2.3 From 55d5b7dd6451b58489ce384282ca5a4a289eb8d5 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Fri, 11 Dec 2020 13:36:42 -0800 Subject: initramfs: fix clang build failure There is only one function in init/initramfs.c that is in the .text section, and it is marked __weak. When building with clang-12 and the integrated assembler, this leads to a bug with recordmcount: ./scripts/recordmcount "init/initramfs.o" Cannot find symbol for section 2: .text. init/initramfs.o: failed I'm not quite sure what exactly goes wrong, but I notice that this function is only ever called from an __init function, and normally inlined. Marking it __init as well is clearly correct and it leads to recordmcount no longer complaining. Link: https://lkml.kernel.org/r/20201204165742.3815221-1-arnd@kernel.org Signed-off-by: Arnd Bergmann Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Barret Rhoden Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- init/initramfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'init') diff --git a/init/initramfs.c b/init/initramfs.c index 1f97c0328a7a..55b74d7e5260 100644 --- a/init/initramfs.c +++ b/init/initramfs.c @@ -535,7 +535,7 @@ extern unsigned long __initramfs_size; #include #include -void __weak free_initrd_mem(unsigned long start, unsigned long end) +void __weak __init free_initrd_mem(unsigned long start, unsigned long end) { #ifdef CONFIG_ARCH_KEEP_MEMBLOCK unsigned long aligned_start = ALIGN_DOWN(start, PAGE_SIZE); -- cgit v1.2.3