Commit be779f03 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'kbuild-v4.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull more Kbuild updates from Masahiro Yamada:

 - fix some bugs introduced by the recent Kconfig syntax extension

 - add some symbols about compiler information in Kconfig, such as
   CC_IS_GCC, CC_IS_CLANG, GCC_VERSION, etc.

 - test compiler capability for the stack protector in Kconfig, and
   clean-up Makefile

 - test compiler capability for GCC-plugins in Kconfig, and clean-up
   Makefile

 - allow to enable GCC-plugins for COMPILE_TEST

 - test compiler capability for KCOV in Kconfig and correct dependency

 - remove auto-detect mode of the GCOV format, which is now more nicely
   handled in Kconfig

 - test compiler capability for mprofile-kernel on PowerPC, and clean-up
   Makefile

 - misc cleanups

* tag 'kbuild-v4.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  linux/linkage.h: replace VMLINUX_SYMBOL_STR() with __stringify()
  kconfig: fix localmodconfig
  sh: remove no-op macro VMLINUX_SYMBOL()
  powerpc/kbuild: move -mprofile-kernel check to Kconfig
  Documentation: kconfig: add recommended way to describe compiler support
  gcc-plugins: disable GCC_PLUGIN_STRUCTLEAK_BYREF_ALL for COMPILE_TEST
  gcc-plugins: allow to enable GCC_PLUGINS for COMPILE_TEST
  gcc-plugins: test plugin support in Kconfig and clean up Makefile
  gcc-plugins: move GCC version check for PowerPC to Kconfig
  kcov: test compiler capability in Kconfig and correct dependency
  gcov: remove CONFIG_GCOV_FORMAT_AUTODETECT
  arm64: move GCC version check for ARCH_SUPPORTS_INT128 to Kconfig
  kconfig: add CC_IS_CLANG and CLANG_VERSION
  kconfig: add CC_IS_GCC and GCC_VERSION
  stack-protector: test compiler capability in Kconfig and drop AUTO mode
  kbuild: fix endless syncconfig in case arch Makefile sets CROSS_COMPILE
parents d290ef93 00979ce4
......@@ -473,6 +473,24 @@ config option to 'y' no matter the dependencies.
The dependencies are moved to the symbol GENERIC_IOMAP and we avoid the
situation where select forces a symbol equals to 'y'.
Adding features that need compiler support
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
There are several features that need compiler support. The recommended way
to describe the dependency on the compiler feature is to use "depends on"
followed by a test macro.
config CC_STACKPROTECTOR
bool "Stack Protector buffer overflow detection"
depends on $(cc-option,-fstack-protector)
...
If you need to expose a compiler capability to makefiles and/or C source files,
CC_HAS_ is the recommended prefix for the config option.
config CC_HAS_STACKPROTECTOR_NONE
def_bool $(cc-option,-fno-stack-protector)
Build as module only
~~~~~~~~~~~~~~~~~~~~
To restrict a component build to module-only, qualify its config symbol
......
......@@ -442,8 +442,6 @@ export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
export KBUILD_ARFLAGS
export CC_VERSION_TEXT := $(shell $(CC) --version | head -n 1)
# When compiling out-of-tree modules, put MODVERDIR in the module
# tree rather than in the kernel tree. The kernel tree might
# even be read-only.
......@@ -514,6 +512,12 @@ ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/cc-can-link.sh $(CC)), y)
export CC_CAN_LINK
endif
# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
# and from include/config/auto.conf.cmd to detect the compiler upgrade.
CC_VERSION_TEXT = $(shell $(CC) --version | head -n 1)
ifeq ($(config-targets),1)
# ===========================================================================
# *config targets only - make sure prerequisites are updated, and descend
......@@ -523,7 +527,7 @@ ifeq ($(config-targets),1)
# KBUILD_DEFCONFIG may point out an alternative default configuration
# used for 'make defconfig'
include arch/$(SRCARCH)/Makefile
export KBUILD_DEFCONFIG KBUILD_KCONFIG
export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
config: scripts_basic outputmakefile FORCE
$(Q)$(MAKE) $(build)=scripts/kconfig $@
......@@ -585,12 +589,32 @@ virt-y := virt/
endif # KBUILD_EXTMOD
ifeq ($(dot-config),1)
# Read in config
-include include/config/auto.conf
endif
# The all: target is the default when no target is given on the
# command line.
# This allow a user to issue only 'make' to build a kernel including modules
# Defaults to vmlinux, but the arch makefile usually adds further targets
all: vmlinux
CFLAGS_GCOV := -fprofile-arcs -ftest-coverage \
$(call cc-option,-fno-tree-loop-im) \
$(call cc-disable-warning,maybe-uninitialized,)
export CFLAGS_GCOV
# The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
# values of the respective KBUILD_* variables
ARCH_CPPFLAGS :=
ARCH_AFLAGS :=
ARCH_CFLAGS :=
include arch/$(SRCARCH)/Makefile
ifeq ($(dot-config),1)
ifeq ($(KBUILD_EXTMOD),)
# Read in dependencies to all Kconfig* files, make sure to run
# oldconfig if changes are detected.
# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
# because some architectures define CROSS_COMPILE there.
-include include/config/auto.conf.cmd
# To avoid any implicit rule to kick in, define an empty command
......@@ -622,24 +646,6 @@ else
include/config/auto.conf: ;
endif # $(dot-config)
# The all: target is the default when no target is given on the
# command line.
# This allow a user to issue only 'make' to build a kernel including modules
# Defaults to vmlinux, but the arch makefile usually adds further targets
all: vmlinux
CFLAGS_GCOV := -fprofile-arcs -ftest-coverage \
$(call cc-option,-fno-tree-loop-im) \
$(call cc-disable-warning,maybe-uninitialized,)
export CFLAGS_GCOV CFLAGS_KCOV
# The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
# values of the respective KBUILD_* variables
ARCH_CPPFLAGS :=
ARCH_AFLAGS :=
ARCH_CFLAGS :=
include arch/$(SRCARCH)/Makefile
KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
......@@ -680,55 +686,11 @@ ifneq ($(CONFIG_FRAME_WARN),0)
KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
endif
# This selects the stack protector compiler flag. Testing it is delayed
# until after .config has been reprocessed, in the prepare-compiler-check
# target.
ifdef CONFIG_CC_STACKPROTECTOR_AUTO
stackp-flag := $(call cc-option,-fstack-protector-strong,$(call cc-option,-fstack-protector))
stackp-name := AUTO
else
ifdef CONFIG_CC_STACKPROTECTOR_REGULAR
stackp-flag := -fstack-protector
stackp-name := REGULAR
else
ifdef CONFIG_CC_STACKPROTECTOR_STRONG
stackp-flag := -fstack-protector-strong
stackp-name := STRONG
else
# If either there is no stack protector for this architecture or
# CONFIG_CC_STACKPROTECTOR_NONE is selected, we're done, and $(stackp-name)
# is empty, skipping all remaining stack protector tests.
#
# Force off for distro compilers that enable stack protector by default.
KBUILD_CFLAGS += $(call cc-option, -fno-stack-protector)
endif
endif
endif
# Find arch-specific stack protector compiler sanity-checking script.
ifdef stackp-name
ifneq ($(stackp-flag),)
stackp-path := $(srctree)/scripts/gcc-$(SRCARCH)_$(BITS)-has-stack-protector.sh
stackp-check := $(wildcard $(stackp-path))
# If the wildcard test matches a test script, run it to check functionality.
ifdef stackp-check
ifneq ($(shell $(CONFIG_SHELL) $(stackp-check) $(CC) $(KBUILD_CPPFLAGS) $(biarch)),y)
stackp-broken := y
endif
endif
ifndef stackp-broken
# If the stack protector is functional, enable code that depends on it.
KBUILD_CPPFLAGS += -DCONFIG_CC_STACKPROTECTOR
# Either we've already detected the flag (for AUTO) or we'll fail the
# build in the prepare-compiler-check rule (for specific flag).
KBUILD_CFLAGS += $(stackp-flag)
else
# We have to make sure stack protector is unconditionally disabled if
# the compiler is broken (in case we're going to continue the build in
# AUTO mode).
KBUILD_CFLAGS += $(call cc-option, -fno-stack-protector)
endif
endif
endif
stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
stackp-flags-$(CONFIG_CC_STACKPROTECTOR) := -fstack-protector
stackp-flags-$(CONFIG_CC_STACKPROTECTOR_STRONG) := -fstack-protector-strong
KBUILD_CFLAGS += $(stackp-flags-y)
ifeq ($(cc-name),clang)
KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
......@@ -1112,7 +1074,7 @@ endif
# prepare2 creates a makefile if using a separate output directory.
# From this point forward, .config has been reprocessed, so any rules
# that need to depend on updated CONFIG_* values can be checked here.
prepare2: prepare3 prepare-compiler-check outputmakefile asm-generic
prepare2: prepare3 outputmakefile asm-generic
prepare1: prepare2 $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
include/config/auto.conf
......@@ -1138,43 +1100,6 @@ uapi-asm-generic:
PHONY += prepare-objtool
prepare-objtool: $(objtool_target)
# Check for CONFIG flags that require compiler support. Abort the build
# after .config has been processed, but before the kernel build starts.
#
# For security-sensitive CONFIG options, we don't want to fallback and/or
# silently change which compiler flags will be used, since that leads to
# producing kernels with different security feature characteristics
# depending on the compiler used. (For example, "But I selected
# CC_STACKPROTECTOR_STRONG! Why did it build with _REGULAR?!")
PHONY += prepare-compiler-check
prepare-compiler-check: FORCE
# Make sure compiler supports requested stack protector flag.
ifdef stackp-name
# Warn about CONFIG_CC_STACKPROTECTOR_AUTO having found no option.
ifeq ($(stackp-flag),)
@echo CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
Compiler does not support any known stack-protector >&2
else
# Fail if specifically requested stack protector is missing.
ifeq ($(call cc-option, $(stackp-flag)),)
@echo Cannot use CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
$(stackp-flag) not supported by compiler >&2 && exit 1
endif
endif
endif
# Make sure compiler does not have buggy stack-protector support. If a
# specific stack-protector was requested, fail the build, otherwise warn.
ifdef stackp-broken
ifeq ($(stackp-name),AUTO)
@echo CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
$(stackp-flag) available but compiler is broken: disabling >&2
else
@echo Cannot use CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
$(stackp-flag) available but compiler is broken >&2 && exit 1
endif
endif
@:
# Generate some files
# ---------------------------------------------------------------------------
......
......@@ -405,6 +405,15 @@ config SECCOMP_FILTER
See Documentation/prctl/seccomp_filter.txt for details.
preferred-plugin-hostcc := $(if-success,[ $(gcc-version) -ge 40800 ],$(HOSTCXX),$(HOSTCC))
config PLUGIN_HOSTCC
string
default "$(shell,$(srctree)/scripts/gcc-plugin.sh "$(preferred-plugin-hostcc)" "$(HOSTCXX)" "$(CC)")"
help
Host compiler used to build GCC plugins. This can be $(HOSTCXX),
$(HOSTCC), or a null string if GCC plugin is unsupported.
config HAVE_GCC_PLUGINS
bool
help
......@@ -414,7 +423,7 @@ config HAVE_GCC_PLUGINS
menuconfig GCC_PLUGINS
bool "GCC plugins"
depends on HAVE_GCC_PLUGINS
depends on !COMPILE_TEST
depends on PLUGIN_HOSTCC != ""
help
GCC plugins are loadable modules that provide extra features to the
compiler. They are useful for runtime instrumentation and static analysis.
......@@ -424,7 +433,7 @@ menuconfig GCC_PLUGINS
config GCC_PLUGIN_CYC_COMPLEXITY
bool "Compute the cyclomatic complexity of a function" if EXPERT
depends on GCC_PLUGINS
depends on !COMPILE_TEST
depends on !COMPILE_TEST # too noisy
help
The complexity M of a function's control flow graph is defined as:
M = E - N + 2P
......@@ -484,6 +493,7 @@ config GCC_PLUGIN_STRUCTLEAK
config GCC_PLUGIN_STRUCTLEAK_BYREF_ALL
bool "Force initialize all struct type variables passed by reference"
depends on GCC_PLUGIN_STRUCTLEAK
depends on !COMPILE_TEST
help
Zero initialize any struct type local variable that may be passed by
reference without having been initialized.
......@@ -491,7 +501,7 @@ config GCC_PLUGIN_STRUCTLEAK_BYREF_ALL
config GCC_PLUGIN_STRUCTLEAK_VERBOSE
bool "Report forcefully initialized variables"
depends on GCC_PLUGIN_STRUCTLEAK
depends on !COMPILE_TEST
depends on !COMPILE_TEST # too noisy
help
This option will cause a warning to be printed each time the
structleak plugin finds a variable it thinks needs to be
......@@ -531,7 +541,7 @@ config GCC_PLUGIN_RANDSTRUCT
config GCC_PLUGIN_RANDSTRUCT_PERFORMANCE
bool "Use cacheline-aware structure randomization"
depends on GCC_PLUGIN_RANDSTRUCT
depends on !COMPILE_TEST
depends on !COMPILE_TEST # do not reduce test coverage
help
If you say Y here, the RANDSTRUCT randomization will make a
best effort at restricting randomization to cacheline-sized
......@@ -543,13 +553,16 @@ config HAVE_CC_STACKPROTECTOR
bool
help
An arch should select this symbol if:
- its compiler supports the -fstack-protector option
- it has implemented a stack canary (e.g. __stack_chk_guard)
choice
prompt "Stack Protector buffer overflow detection"
config CC_HAS_STACKPROTECTOR_NONE
def_bool $(cc-option,-fno-stack-protector)
config CC_STACKPROTECTOR
bool "Stack Protector buffer overflow detection"
depends on HAVE_CC_STACKPROTECTOR
default CC_STACKPROTECTOR_AUTO
depends on $(cc-option,-fstack-protector)
default y
help
This option turns on the "stack-protector" GCC feature. This
feature puts, at the beginning of functions, a canary value on
......@@ -559,14 +572,6 @@ choice
overwrite the canary, which gets detected and the attack is then
neutralized via a kernel panic.
config CC_STACKPROTECTOR_NONE
bool "None"
help
Disable "stack-protector" GCC feature.
config CC_STACKPROTECTOR_REGULAR
bool "Regular"
help
Functions will have the stack-protector canary logic added if they
have an 8-byte or larger character array on the stack.
......@@ -578,7 +583,10 @@ config CC_STACKPROTECTOR_REGULAR
by about 0.3%.
config CC_STACKPROTECTOR_STRONG
bool "Strong"
bool "Strong Stack Protector"
depends on CC_STACKPROTECTOR
depends on $(cc-option,-fstack-protector-strong)
default y
help
Functions will have the stack-protector canary logic added in any
of the following conditions:
......@@ -596,14 +604,6 @@ config CC_STACKPROTECTOR_STRONG
about 20% of all kernel functions, which increases the kernel code
size by about 2%.
config CC_STACKPROTECTOR_AUTO
bool "Automatic"
help
If the compiler supports it, the best available stack-protector
option will be chosen.
endchoice
config HAVE_ARCH_WITHIN_STACK_FRAMES
bool
help
......
......@@ -46,6 +46,7 @@ config ARM64
select ARCH_USE_QUEUED_RWLOCKS
select ARCH_SUPPORTS_MEMORY_FAILURE
select ARCH_SUPPORTS_ATOMIC_RMW
select ARCH_SUPPORTS_INT128 if GCC_VERSION >= 50000 || CC_IS_CLANG
select ARCH_SUPPORTS_NUMA_BALANCING
select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
select ARCH_WANT_FRAME_POINTERS
......
......@@ -56,12 +56,6 @@ KBUILD_AFLAGS += $(lseinstr) $(brokengasinst)
KBUILD_CFLAGS += $(call cc-option,-mabi=lp64)
KBUILD_AFLAGS += $(call cc-option,-mabi=lp64)
ifeq ($(cc-name),clang)
KBUILD_CFLAGS += -DCONFIG_ARCH_SUPPORTS_INT128
else
KBUILD_CFLAGS += $(call cc-ifversion, -ge, 0500, -DCONFIG_ARCH_SUPPORTS_INT128)
endif
ifeq ($(CONFIG_CPU_BIG_ENDIAN), y)
KBUILD_CPPFLAGS += -mbig-endian
CHECKFLAGS += -D__AARCH64EB__
......
......@@ -190,7 +190,7 @@ config PPC
select HAVE_FTRACE_MCOUNT_RECORD
select HAVE_FUNCTION_GRAPH_TRACER
select HAVE_FUNCTION_TRACER
select HAVE_GCC_PLUGINS
select HAVE_GCC_PLUGINS if GCC_VERSION >= 50200 # plugin support on gcc <= 5.1 is buggy on PPC
select HAVE_GENERIC_GUP
select HAVE_HW_BREAKPOINT if PERF_EVENTS && (PPC_BOOK3S || PPC_8xx)
select HAVE_IDE
......@@ -461,23 +461,9 @@ config LD_HEAD_STUB_CATCH
If unsure, say "N".
config DISABLE_MPROFILE_KERNEL
bool "Disable use of mprofile-kernel for kernel tracing"
depends on PPC64 && CPU_LITTLE_ENDIAN
default y
help
Selecting this options disables use of the mprofile-kernel ABI for
kernel tracing. That will cause options such as live patching
(CONFIG_LIVEPATCH) which depend on CONFIG_DYNAMIC_FTRACE_WITH_REGS to
be disabled also.
If you have a toolchain which supports mprofile-kernel, then you can
disable this. Otherwise leave it enabled. If you're not sure, say
"Y".
config MPROFILE_KERNEL
depends on PPC64 && CPU_LITTLE_ENDIAN
def_bool !DISABLE_MPROFILE_KERNEL
def_bool $(success,$(srctree)/arch/powerpc/tools/gcc-check-mprofile-kernel.sh $(CC) -I$(srctree)/include -D__KERNEL__)
config HOTPLUG_CPU
bool "Support for enabling/disabling CPUs"
......
......@@ -161,18 +161,7 @@ CFLAGS-$(CONFIG_GENERIC_CPU) += -mcpu=powerpc64
endif
ifdef CONFIG_MPROFILE_KERNEL
ifeq ($(shell $(srctree)/arch/powerpc/tools/gcc-check-mprofile-kernel.sh $(CC) -I$(srctree)/include -D__KERNEL__),OK)
CC_FLAGS_FTRACE := -pg -mprofile-kernel
KBUILD_CPPFLAGS += -DCC_USING_MPROFILE_KERNEL
else
# If the user asked for mprofile-kernel but the toolchain doesn't
# support it, emit a warning and deliberately break the build later
# with mprofile-kernel-not-supported. We would prefer to make this an
# error right here, but then the user would never be able to run
# oldconfig to change their configuration.
$(warning Compiler does not support mprofile-kernel, set CONFIG_DISABLE_MPROFILE_KERNEL)
CC_FLAGS_FTRACE := -mprofile-kernel-not-supported
endif
CC_FLAGS_FTRACE := -pg -mprofile-kernel
endif
CFLAGS-$(CONFIG_CELL_CPU) += $(call cc-option,-mcpu=cell)
......
......@@ -14,7 +14,7 @@
#include <asm-generic/module.h>
#ifdef CC_USING_MPROFILE_KERNEL
#ifdef CONFIG_MPROFILE_KERNEL
#define MODULE_ARCH_VERMAGIC_FTRACE "mprofile-kernel "
#else
#define MODULE_ARCH_VERMAGIC_FTRACE ""
......
......@@ -466,7 +466,7 @@ static unsigned long stub_for_addr(const Elf64_Shdr *sechdrs,
return (unsigned long)&stubs[i];
}
#ifdef CC_USING_MPROFILE_KERNEL
#ifdef CONFIG_MPROFILE_KERNEL
static bool is_mprofile_mcount_callsite(const char *name, u32 *instruction)
{
if (strcmp("_mcount", name))
......@@ -753,7 +753,7 @@ int apply_relocate_add(Elf64_Shdr *sechdrs,
#ifdef CONFIG_DYNAMIC_FTRACE
#ifdef CC_USING_MPROFILE_KERNEL
#ifdef CONFIG_MPROFILE_KERNEL
#define PACATOC offsetof(struct paca_struct, kernel_toc)
......
......@@ -144,7 +144,7 @@ __ftrace_make_nop(struct module *mod,
return -EINVAL;
}
#ifdef CC_USING_MPROFILE_KERNEL
#ifdef CONFIG_MPROFILE_KERNEL
/* When using -mkernel_profile there is no load to jump over */
pop = PPC_INST_NOP;
......@@ -188,7 +188,7 @@ __ftrace_make_nop(struct module *mod,
pr_err("Expected %08x found %08x\n", PPC_INST_LD_TOC, op);
return -EINVAL;
}
#endif /* CC_USING_MPROFILE_KERNEL */
#endif /* CONFIG_MPROFILE_KERNEL */
if (patch_instruction((unsigned int *)ip, pop)) {
pr_err("Patching NOP failed.\n");
......@@ -324,7 +324,7 @@ int ftrace_make_nop(struct module *mod,
* They should effectively be a NOP, and follow formal constraints,
* depending on the ABI. Return false if they don't.
*/
#ifndef CC_USING_MPROFILE_KERNEL
#ifndef CONFIG_MPROFILE_KERNEL
static int
expected_nop_sequence(void *ip, unsigned int op0, unsigned int op1)
{
......
......@@ -24,5 +24,4 @@ echo -e "#include <linux/compiler.h>\nnotrace int func() { return 0; }" | \
2> /dev/null | grep -q "_mcount" && \
exit 1
echo "OK"
exit 0
......@@ -7,9 +7,9 @@
#ifdef CONFIG_DWARF_UNWINDER
#define DWARF_EH_FRAME \
.eh_frame : AT(ADDR(.eh_frame) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start_eh_frame) = .; \
__start_eh_frame = .; \
*(.eh_frame) \
VMLINUX_SYMBOL(__stop_eh_frame) = .; \
__stop_eh_frame = .; \
}
#else
#define DWARF_EH_FRAME
......
......@@ -130,7 +130,7 @@ config X86
select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
select HAVE_ARCH_VMAP_STACK if X86_64
select HAVE_ARCH_WITHIN_STACK_FRAMES
select HAVE_CC_STACKPROTECTOR
select HAVE_CC_STACKPROTECTOR if CC_HAS_SANE_STACKPROTECTOR
select HAVE_CMPXCHG_DOUBLE
select HAVE_CMPXCHG_LOCAL
select HAVE_CONTEXT_TRACKING if X86_64
......@@ -346,6 +346,15 @@ config PGTABLE_LEVELS
default 2
source "init/Kconfig"
config CC_HAS_SANE_STACKPROTECTOR
bool
default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC)) if 64BIT
default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC))
help
We have to make sure stack protector is unconditionally disabled if
the compiler produces broken code.
source "kernel/Kconfig.freezer"
menu "Processor type and features"
......
......@@ -24,16 +24,16 @@
#ifndef cond_syscall
#define cond_syscall(x) asm( \
".weak " VMLINUX_SYMBOL_STR(x) "\n\t" \
".set " VMLINUX_SYMBOL_STR(x) "," \
VMLINUX_SYMBOL_STR(sys_ni_syscall))
".weak " __stringify(x) "\n\t" \
".set " __stringify(x) "," \
__stringify(sys_ni_syscall))
#endif
#ifndef SYSCALL_ALIAS
#define SYSCALL_ALIAS(alias, name) asm( \
".globl " VMLINUX_SYMBOL_STR(alias) "\n\t" \
".set " VMLINUX_SYMBOL_STR(alias) "," \
VMLINUX_SYMBOL_STR(name))
".globl " __stringify(alias) "\n\t" \
".set " __stringify(alias) "," \
__stringify(name))
#endif
#define __page_aligned_data __section(.data..page_aligned) __aligned(PAGE_SIZE)
......
......@@ -8,6 +8,21 @@ config DEFCONFIG_LIST
default ARCH_DEFCONFIG
default "arch/$(ARCH)/defconfig"
config CC_IS_GCC
def_bool $(success,$(CC) --version | head -n 1 | grep -q gcc)
config GCC_VERSION
int
default $(shell,$(srctree)/scripts/gcc-version.sh -p $(CC) | sed 's/^0*//') if CC_IS_GCC
default 0
config CC_IS_CLANG
def_bool $(success,$(CC) --version | head -n 1 | grep -q clang)
config CLANG_VERSION
int
default $(shell,$(srctree)/scripts/clang-version.sh $(CC))
config CONSTRUCTORS
bool
depends on !UML
......
......@@ -53,23 +53,16 @@ config GCOV_PROFILE_ALL
choice
prompt "Specify GCOV format"
depends on GCOV_KERNEL
default GCOV_FORMAT_AUTODETECT
---help---
The gcov format is usually determined by the GCC version, but there are
The gcov format is usually determined by the GCC version, and the
default is chosen according to your GCC version. However, there are
exceptions where format changes are integrated in lower-version GCCs.
In such a case use this option to adjust the format used in the kernel
accordingly.
If unsure, choose "Autodetect".
config GCOV_FORMAT_AUTODETECT
bool "Autodetect"
---help---
Select this option to use the format that corresponds to your GCC
version.
In such a case, change this option to adjust the format used in the
kernel accordingly.
config GCOV_FORMAT_3_4
bool "GCC 3.4 format"
depends on CC_IS_GCC && GCC_VERSION < 40700
---help---
Select this option to use the format defined by GCC 3.4.
......
......@@ -4,5 +4,3 @@ ccflags-y := -DSRCTREE='"$(srctree)"' -DOBJTREE='"$(objtree)"'
obj-y := base.o fs.o
obj-$(CONFIG_GCOV_FORMAT_3_4) += gcc_3_4.o
obj-$(CONFIG_GCOV_FORMAT_4_7) += gcc_4_7.o
obj-$(CONFIG_GCOV_FORMAT_AUTODETECT) += $(call cc-ifversion, -lt, 0407, \
gcc_3_4.o, gcc_4_7.o)
......@@ -736,12 +736,15 @@ config ARCH_HAS_KCOV
only for x86_64. KCOV requires testing on other archs, and most likely
disabling of instrumentation for some early boot code.
config CC_HAS_SANCOV_TRACE_PC
def_bool $(cc-option,-fsanitize-coverage=trace-pc)
config KCOV
bool "Code coverage for fuzzing"
depends on ARCH_HAS_KCOV
depends on CC_HAS_SANCOV_TRACE_PC || GCC_PLUGINS
select DEBUG_FS
select GCC_PLUGINS if !COMPILE_TEST
select GCC_PLUGIN_SANCOV if !COMPILE_TEST
select GCC_PLUGIN_SANCOV if !CC_HAS_SANCOV_TRACE_PC
help
KCOV exposes kernel code coverage information in a form suitable
for coverage-guided fuzzing (randomized testing).
......@@ -755,7 +758,7 @@ config KCOV
config KCOV_ENABLE_COMPARISONS
bool "Enable comparison operands collection by KCOV"
depends on KCOV
default n
depends on $(cc-option,-fsanitize-coverage=trace-cmp)
help
KCOV also exposes operands of every comparison in the instrumented
code along with operand sizes and PCs of the comparison instructions.
......@@ -765,7 +768,7 @@ config KCOV_ENABLE_COMPARISONS
config KCOV_INSTRUMENT_ALL
bool "Instrument all code by default"
depends on KCOV
default y if KCOV
default y
help
If you are doing generic system call fuzzing (like e.g. syzkaller),
then you will want to instrument the whole kernel and you should
......