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-rw-r--r--arch/Kconfig253
1 files changed, 245 insertions, 8 deletions
diff --git a/arch/Kconfig b/arch/Kconfig
index a5af0edd3eb8..b8a4ff365582 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -9,6 +9,23 @@
#
source "arch/$(SRCARCH)/Kconfig"
+config ARCH_CONFIGURES_CPU_MITIGATIONS
+ bool
+
+if !ARCH_CONFIGURES_CPU_MITIGATIONS
+config CPU_MITIGATIONS
+ def_bool y
+endif
+
+#
+# Selected by architectures that need custom DMA operations for e.g. legacy
+# IOMMUs not handled by dma-iommu. Drivers must never select this symbol.
+#
+config ARCH_HAS_DMA_OPS
+ depends on HAS_DMA
+ select DMA_OPS_HELPERS
+ bool
+
menu "General architecture-dependent options"
config ARCH_HAS_SUBPAGE_FAULTS
@@ -52,10 +69,10 @@ config GENERIC_ENTRY
config KPROBES
bool "Kprobes"
- depends on MODULES
depends on HAVE_KPROBES
select KALLSYMS
- select TASKS_RCU if PREEMPTION
+ select EXECMEM
+ select NEED_TASKS_RCU
help
Kprobes allows you to trap at almost any kernel address and
execute a callback function. register_kprobe() establishes
@@ -104,7 +121,7 @@ config STATIC_CALL_SELFTEST
config OPTPROBES
def_bool y
depends on KPROBES && HAVE_OPTPROBES
- select TASKS_RCU if PREEMPTION
+ select NEED_TASKS_RCU
config KPROBES_ON_FTRACE
def_bool y
@@ -118,6 +135,7 @@ config KPROBES_ON_FTRACE
config UPROBES
def_bool n
depends on ARCH_SUPPORTS_UPROBES
+ select TASKS_TRACE_RCU
help
Uprobes is the user-space counterpart to kprobes: they
enable instrumentation applications (such as 'perf probe')
@@ -502,6 +520,15 @@ config MMU_LAZY_TLB_SHOOTDOWN
config ARCH_HAVE_NMI_SAFE_CMPXCHG
bool
+config ARCH_HAVE_EXTRA_ELF_NOTES
+ bool
+ help
+ An architecture should select this in order to enable adding an
+ arch-specific ELF note section to core files. It must provide two
+ functions: elf_coredump_extra_notes_size() and
+ elf_coredump_extra_notes_write() which are invoked by the ELF core
+ dumper.
+
config ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
bool
@@ -785,6 +812,45 @@ config LTO_CLANG_THIN
If unsure, say Y.
endchoice
+config ARCH_SUPPORTS_AUTOFDO_CLANG
+ bool
+
+config AUTOFDO_CLANG
+ bool "Enable Clang's AutoFDO build (EXPERIMENTAL)"
+ depends on ARCH_SUPPORTS_AUTOFDO_CLANG
+ depends on CC_IS_CLANG && CLANG_VERSION >= 170000
+ help
+ This option enables Clang’s AutoFDO build. When
+ an AutoFDO profile is specified in variable
+ CLANG_AUTOFDO_PROFILE during the build process,
+ Clang uses the profile to optimize the kernel.
+
+ If no profile is specified, AutoFDO options are
+ still passed to Clang to facilitate the collection
+ of perf data for creating an AutoFDO profile in
+ subsequent builds.
+
+ If unsure, say N.
+
+config ARCH_SUPPORTS_PROPELLER_CLANG
+ bool
+
+config PROPELLER_CLANG
+ bool "Enable Clang's Propeller build"
+ depends on ARCH_SUPPORTS_PROPELLER_CLANG
+ depends on CC_IS_CLANG && CLANG_VERSION >= 190000
+ help
+ This option enables Clang’s Propeller build. When the Propeller
+ profiles is specified in variable CLANG_PROPELLER_PROFILE_PREFIX
+ during the build process, Clang uses the profiles to optimize
+ the kernel.
+
+ If no profile is specified, Propeller options are still passed
+ to Clang to facilitate the collection of perf data for creating
+ the Propeller profiles in subsequent builds.
+
+ If unsure, say N.
+
config ARCH_SUPPORTS_CFI_CLANG
bool
help
@@ -799,7 +865,7 @@ config CFI_CLANG
depends on ARCH_SUPPORTS_CFI_CLANG
depends on $(cc-option,-fsanitize=kcfi)
help
- This option enables Clang’s forward-edge Control Flow Integrity
+ This option enables Clang's forward-edge Control Flow Integrity
(CFI) checking, where the compiler injects a runtime check to each
indirect function call to ensure the target is a valid function with
the correct static type. This restricts possible call targets and
@@ -809,6 +875,36 @@ config CFI_CLANG
https://clang.llvm.org/docs/ControlFlowIntegrity.html
+config CFI_ICALL_NORMALIZE_INTEGERS
+ bool "Normalize CFI tags for integers"
+ depends on CFI_CLANG
+ depends on HAVE_CFI_ICALL_NORMALIZE_INTEGERS_CLANG
+ help
+ This option normalizes the CFI tags for integer types so that all
+ integer types of the same size and signedness receive the same CFI
+ tag.
+
+ The option is separate from CONFIG_RUST because it affects the ABI.
+ When working with build systems that care about the ABI, it is
+ convenient to be able to turn on this flag first, before Rust is
+ turned on.
+
+ This option is necessary for using CFI with Rust. If unsure, say N.
+
+config HAVE_CFI_ICALL_NORMALIZE_INTEGERS_CLANG
+ def_bool y
+ depends on $(cc-option,-fsanitize=kcfi -fsanitize-cfi-icall-experimental-normalize-integers)
+ # With GCOV/KASAN we need this fix: https://github.com/llvm/llvm-project/pull/104826
+ depends on CLANG_VERSION >= 190103 || (!GCOV_KERNEL && !KASAN_GENERIC && !KASAN_SW_TAGS)
+
+config HAVE_CFI_ICALL_NORMALIZE_INTEGERS_RUSTC
+ def_bool y
+ depends on HAVE_CFI_ICALL_NORMALIZE_INTEGERS_CLANG
+ depends on RUSTC_VERSION >= 107900
+ # With GCOV/KASAN we need this fix: https://github.com/rust-lang/rust/pull/129373
+ depends on (RUSTC_LLVM_VERSION >= 190103 && RUSTC_VERSION >= 108200) || \
+ (!GCOV_KERNEL && !KASAN_GENERIC && !KASAN_SW_TAGS)
+
config CFI_PERMISSIVE
bool "Use CFI in permissive mode"
depends on CFI_CLANG
@@ -845,7 +941,7 @@ config HAVE_CONTEXT_TRACKING_USER_OFFSTACK
Architecture neither relies on exception_enter()/exception_exit()
nor on schedule_user(). Also preempt_schedule_notrace() and
preempt_schedule_irq() can't be called in a preemptible section
- while context tracking is CONTEXT_USER. This feature reflects a sane
+ while context tracking is CT_STATE_USER. This feature reflects a sane
entry implementation where the following requirements are met on
critical entry code, ie: before user_exit() or after user_enter():
@@ -960,6 +1056,22 @@ config ARCH_WANTS_MODULES_DATA_IN_VMALLOC
For architectures like powerpc/32 which have constraints on module
allocation and need to allocate module data outside of module area.
+config ARCH_WANTS_EXECMEM_LATE
+ bool
+ help
+ For architectures that do not allocate executable memory early on
+ boot, but rather require its initialization late when there is
+ enough entropy for module space randomization, for instance
+ arm64.
+
+config ARCH_HAS_EXECMEM_ROX
+ bool
+ depends on MMU && !HIGHMEM
+ help
+ For architectures that support allocations of executable memory
+ with read-only execute permissions. Architecture must implement
+ execmem_fill_trapping_insns() callback to enable this.
+
config HAVE_IRQ_EXIT_ON_IRQ_STACK
bool
help
@@ -1078,17 +1190,107 @@ config HAVE_ARCH_COMPAT_MMAP_BASES
and vice-versa 32-bit applications to call 64-bit mmap().
Required for applications doing different bitness syscalls.
+config HAVE_PAGE_SIZE_4KB
+ bool
+
+config HAVE_PAGE_SIZE_8KB
+ bool
+
+config HAVE_PAGE_SIZE_16KB
+ bool
+
+config HAVE_PAGE_SIZE_32KB
+ bool
+
+config HAVE_PAGE_SIZE_64KB
+ bool
+
+config HAVE_PAGE_SIZE_256KB
+ bool
+
+choice
+ prompt "MMU page size"
+
+config PAGE_SIZE_4KB
+ bool "4KiB pages"
+ depends on HAVE_PAGE_SIZE_4KB
+ help
+ This option select the standard 4KiB Linux page size and the only
+ available option on many architectures. Using 4KiB page size will
+ minimize memory consumption and is therefore recommended for low
+ memory systems.
+ Some software that is written for x86 systems makes incorrect
+ assumptions about the page size and only runs on 4KiB pages.
+
+config PAGE_SIZE_8KB
+ bool "8KiB pages"
+ depends on HAVE_PAGE_SIZE_8KB
+ help
+ This option is the only supported page size on a few older
+ processors, and can be slightly faster than 4KiB pages.
+
+config PAGE_SIZE_16KB
+ bool "16KiB pages"
+ depends on HAVE_PAGE_SIZE_16KB
+ help
+ This option is usually a good compromise between memory
+ consumption and performance for typical desktop and server
+ workloads, often saving a level of page table lookups compared
+ to 4KB pages as well as reducing TLB pressure and overhead of
+ per-page operations in the kernel at the expense of a larger
+ page cache.
+
+config PAGE_SIZE_32KB
+ bool "32KiB pages"
+ depends on HAVE_PAGE_SIZE_32KB
+ help
+ Using 32KiB page size will result in slightly higher performance
+ kernel at the price of higher memory consumption compared to
+ 16KiB pages. This option is available only on cnMIPS cores.
+ Note that you will need a suitable Linux distribution to
+ support this.
+
+config PAGE_SIZE_64KB
+ bool "64KiB pages"
+ depends on HAVE_PAGE_SIZE_64KB
+ help
+ Using 64KiB page size will result in slightly higher performance
+ kernel at the price of much higher memory consumption compared to
+ 4KiB or 16KiB pages.
+ This is not suitable for general-purpose workloads but the
+ better performance may be worth the cost for certain types of
+ supercomputing or database applications that work mostly with
+ large in-memory data rather than small files.
+
+config PAGE_SIZE_256KB
+ bool "256KiB pages"
+ depends on HAVE_PAGE_SIZE_256KB
+ help
+ 256KiB pages have little practical value due to their extreme
+ memory usage. The kernel will only be able to run applications
+ that have been compiled with '-zmax-page-size' set to 256KiB
+ (the default is 64KiB or 4KiB on most architectures).
+
+endchoice
+
config PAGE_SIZE_LESS_THAN_64KB
def_bool y
- depends on !ARM64_64K_PAGES
depends on !PAGE_SIZE_64KB
- depends on !PARISC_PAGE_SIZE_64KB
depends on PAGE_SIZE_LESS_THAN_256KB
config PAGE_SIZE_LESS_THAN_256KB
def_bool y
depends on !PAGE_SIZE_256KB
+config PAGE_SHIFT
+ int
+ default 12 if PAGE_SIZE_4KB
+ default 13 if PAGE_SIZE_8KB
+ default 14 if PAGE_SIZE_16KB
+ default 15 if PAGE_SIZE_32KB
+ default 16 if PAGE_SIZE_64KB
+ default 18 if PAGE_SIZE_256KB
+
# This allows to use a set of generic functions to determine mmap base
# address by giving priority to top-down scheme only if the process
# is not in legacy mode (compat task, unlimited stack size or
@@ -1324,6 +1526,14 @@ config HAVE_ARCH_COMPILER_H
linux/compiler-*.h in order to override macro definitions that those
headers generally provide.
+config HAVE_ARCH_LIBGCC_H
+ bool
+ help
+ An architecture can select this if it provides an
+ asm/libgcc.h header that should be included after
+ linux/libgcc.h in order to override macro definitions that
+ header generally provides.
+
config HAVE_ARCH_PREL32_RELOCATIONS
bool
help
@@ -1374,7 +1584,7 @@ config HAVE_SPARSE_SYSCALL_NR
entries at 4000, 5000 and 6000 locations. This option turns on syscall
related optimizations for a given architecture.
-config ARCH_HAS_VDSO_DATA
+config ARCH_HAS_VDSO_TIME_DATA
bool
config HAVE_STATIC_CALL
@@ -1479,6 +1689,12 @@ config ARCH_HAS_NONLEAF_PMD_YOUNG
address translations. Page table walkers that clear the accessed bit
may use this capability to reduce their search space.
+config ARCH_HAS_KERNEL_FPU_SUPPORT
+ bool
+ help
+ Architectures that select this option can run floating-point code in
+ the kernel, as described in Documentation/core-api/floating-point.rst.
+
source "kernel/gcov/Kconfig"
source "scripts/gcc-plugins/Kconfig"
@@ -1507,4 +1723,25 @@ config FUNCTION_ALIGNMENT
default 4 if FUNCTION_ALIGNMENT_4B
default 0
+config CC_HAS_MIN_FUNCTION_ALIGNMENT
+ # Detect availability of the GCC option -fmin-function-alignment which
+ # guarantees minimal alignment for all functions, unlike
+ # -falign-functions which the compiler ignores for cold functions.
+ def_bool $(cc-option, -fmin-function-alignment=8)
+
+config CC_HAS_SANE_FUNCTION_ALIGNMENT
+ # Set if the guaranteed alignment with -fmin-function-alignment is
+ # available or extra care is required in the kernel. Clang provides
+ # strict alignment always, even with -falign-functions.
+ def_bool CC_HAS_MIN_FUNCTION_ALIGNMENT || CC_IS_CLANG
+
+config ARCH_NEED_CMPXCHG_1_EMU
+ bool
+
+config ARCH_WANTS_PRE_LINK_VMLINUX
+ bool
+ help
+ An architecture can select this if it provides arch/<arch>/tools/Makefile
+ with .arch.vmlinux.o target to be linked into vmlinux.
+
endmenu