config KERNEL_ARM_PMU
bool
+ default y if TARGET_armsr_armv8
depends on (arm || aarch64)
config KERNEL_X86_VSYSCALL_EMULATION
will have no effect.
if KERNEL_KASAN
- config KERNEL_KASAN_GENERIC
- def_bool y
+choice
+ prompt "KASAN mode"
+ depends on KERNEL_KASAN
+ default KERNEL_KASAN_GENERIC
+ help
+ KASAN has three modes:
+
+ 1. Generic KASAN (supported by many architectures, enabled with
+ CONFIG_KASAN_GENERIC, similar to userspace ASan),
+ 2. Software Tag-Based KASAN (arm64 only, based on software memory
+ tagging, enabled with CONFIG_KASAN_SW_TAGS, similar to userspace
+ HWASan), and
+ 3. Hardware Tag-Based KASAN (arm64 only, based on hardware memory
+ tagging, enabled with CONFIG_KASAN_HW_TAGS).
+
+config KERNEL_KASAN_GENERIC
+ bool "Generic KASAN"
+ select KERNEL_SLUB_DEBUG
+ help
+ Enables Generic KASAN.
+
+ Consumes about 1/8th of available memory at kernel start and adds an
+ overhead of ~50% for dynamic allocations.
+ The performance slowdown is ~x3.
+
+config KERNEL_KASAN_SW_TAGS
+ bool "Software Tag-Based KASAN"
+ depends on aarch64
+ select KERNEL_SLUB_DEBUG
+ help
+ Enables Software Tag-Based KASAN.
+
+ Supported only on arm64 CPUs and relies on Top Byte Ignore.
+
+ Consumes about 1/16th of available memory at kernel start and
+ add an overhead of ~20% for dynamic allocations.
+
+ May potentially introduce problems related to pointer casting and
+ comparison, as it embeds a tag into the top byte of each pointer.
+
+config KERNEL_KASAN_HW_TAGS
+ bool "Hardware Tag-Based KASAN"
+ depends on aarch64
+ select KERNEL_SLUB_DEBUG
+ select KERNEL_ARM64_MTE
+ help
+ Enables Hardware Tag-Based KASAN.
+
+ Supported only on arm64 CPUs starting from ARMv8.5 and relies on
+ Memory Tagging Extension and Top Byte Ignore.
+
+ Consumes about 1/32nd of available memory.
+
+ May potentially introduce problems related to pointer casting and
+ comparison, as it embeds a tag into the top byte of each pointer.
+
+endchoice
+
+ config KERNEL_ARM64_MTE
+ def_bool n
- config KERNEL_KASAN_SW_TAGS
- def_bool n
endif
choice
prompt "Instrumentation type"
depends on KERNEL_KASAN
+ depends on !KERNEL_KASAN_HW_TAGS
default KERNEL_KASAN_OUTLINE
config KERNEL_KASAN_OUTLINE
DEBUG_INFO build and compile times are reduced too.
Only works with newer gcc versions.
+config KERNEL_FRAME_WARN
+ int
+ range 0 8192
+ default 1280 if KERNEL_KASAN && !ARCH_64BIT
+ default 1024 if !ARCH_64BIT
+ default 2048 if ARCH_64BIT
+ help
+ Tell the compiler to warn at build time for stack frames larger than this.
+ Setting this too low will cause a lot of warnings.
+ Setting it to 0 disables the warning.
+
# KERNEL_DEBUG_LL symbols must have the default value set as otherwise
# KConfig wont evaluate them unless KERNEL_EARLY_PRINTK is selected
# which means that buildroot wont override the DEBUG_LL symbols in target
default y
config KERNEL_SLUB_DEBUG
- bool
+ bool "Enable SLUB debugging support"
+ help
+ This enables various debugging features:
+ - Accepts "slub_debug" kernel parameter
+ - Provides caches debugging options (e.g. tracing, validating)
+ - Adds /sys/kernel/slab/ attrs for reading amounts of *objects*
+ - Enables /proc/slabinfo support
+ - Prints info when running out of memory
+
+ Enabling this can result in a significant increase of code size.
config KERNEL_SLUB_DEBUG_ON
- bool
+ depends on KERNEL_SLUB_DEBUG
+ bool "Boot kernel with basic caches debugging enabled"
+ help
+ This enables by default sanity_checks, red_zone, poison and store_user
+ debugging options for all caches.
config KERNEL_SLABINFO
select KERNEL_SLUB_DEBUG
This module provides glue between core networking code and device
drivers to support L3 master devices like VRF.
+config KERNEL_XDP_SOCKETS
+ bool "XDP sockets support"
+ help
+ XDP sockets allows a channel between XDP programs and
+ userspace applications.
+
config KERNEL_WIRELESS_EXT
def_bool n
config KERNEL_JFFS2_FS_SECURITY
bool "JFFS2 Security Labels"
+
+config KERNEL_WERROR
+ bool "Compile the kernel with warnings as errors"
+ default BUILDBOT
+ default y if GCC_USE_VERSION_12
+ help
+ A kernel build should not cause any compiler warnings, and this
+ enables the '-Werror' (for C) and '-Dwarnings' (for Rust) flags
+ to enforce that rule by default. Certain warnings from other tools
+ such as the linker may be upgraded to errors with this option as
+ well.
+
+ However, if you have a new (or very old) compiler or linker with odd
+ and unusual warnings, or you have some architecture with problems,
+ you may need to disable this config option in order to
+ successfully build the kernel.