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@@ -0,0 +1,840 @@
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+#
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+# General architecture dependent options
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+#
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+
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+config KEXEC_CORE
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+ bool
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+
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+config OPROFILE
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+ tristate "OProfile system profiling"
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+ depends on PROFILING
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+ depends on HAVE_OPROFILE
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+ select RING_BUFFER
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+ select RING_BUFFER_ALLOW_SWAP
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+ help
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+ OProfile is a profiling system capable of profiling the
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+ whole system, include the kernel, kernel modules, libraries,
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+ and applications.
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+
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+ If unsure, say N.
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+
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+config OPROFILE_EVENT_MULTIPLEX
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+ bool "OProfile multiplexing support (EXPERIMENTAL)"
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+ default n
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+ depends on OPROFILE && X86
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+ help
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+ The number of hardware counters is limited. The multiplexing
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+ feature enables OProfile to gather more events than counters
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+ are provided by the hardware. This is realized by switching
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+ between events at an user specified time interval.
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+
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+ If unsure, say N.
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+
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+config HAVE_OPROFILE
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+ bool
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+
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+config OPROFILE_NMI_TIMER
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+ def_bool y
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+ depends on PERF_EVENTS && HAVE_PERF_EVENTS_NMI && !PPC64
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+
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+config KPROBES
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+ bool "Kprobes"
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+ depends on MODULES
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+ depends on HAVE_KPROBES
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+ select KALLSYMS
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+ help
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+ Kprobes allows you to trap at almost any kernel address and
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+ execute a callback function. register_kprobe() establishes
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+ a probepoint and specifies the callback. Kprobes is useful
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+ for kernel debugging, non-intrusive instrumentation and testing.
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+ If in doubt, say "N".
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+
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+config JUMP_LABEL
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+ bool "Optimize very unlikely/likely branches"
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+ depends on HAVE_ARCH_JUMP_LABEL
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+ help
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+ This option enables a transparent branch optimization that
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+ makes certain almost-always-true or almost-always-false branch
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+ conditions even cheaper to execute within the kernel.
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+
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+ Certain performance-sensitive kernel code, such as trace points,
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+ scheduler functionality, networking code and KVM have such
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+ branches and include support for this optimization technique.
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+
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+ If it is detected that the compiler has support for "asm goto",
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+ the kernel will compile such branches with just a nop
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+ instruction. When the condition flag is toggled to true, the
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+ nop will be converted to a jump instruction to execute the
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+ conditional block of instructions.
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+
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+ This technique lowers overhead and stress on the branch prediction
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+ of the processor and generally makes the kernel faster. The update
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+ of the condition is slower, but those are always very rare.
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+
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+ ( On 32-bit x86, the necessary options added to the compiler
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+ flags may increase the size of the kernel slightly. )
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+
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+config STATIC_KEYS_SELFTEST
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+ bool "Static key selftest"
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+ depends on JUMP_LABEL
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+ help
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+ Boot time self-test of the branch patching code.
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+
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+config OPTPROBES
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+ def_bool y
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+ depends on KPROBES && HAVE_OPTPROBES
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+ depends on !PREEMPT
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+
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+config KPROBES_ON_FTRACE
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+ def_bool y
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+ depends on KPROBES && HAVE_KPROBES_ON_FTRACE
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+ depends on DYNAMIC_FTRACE_WITH_REGS
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+ help
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+ If function tracer is enabled and the arch supports full
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+ passing of pt_regs to function tracing, then kprobes can
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+ optimize on top of function tracing.
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+
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+config UPROBES
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+ def_bool n
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+ help
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+ Uprobes is the user-space counterpart to kprobes: they
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+ enable instrumentation applications (such as 'perf probe')
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+ to establish unintrusive probes in user-space binaries and
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+ libraries, by executing handler functions when the probes
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+ are hit by user-space applications.
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+
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+ ( These probes come in the form of single-byte breakpoints,
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+ managed by the kernel and kept transparent to the probed
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+ application. )
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+
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+config HAVE_64BIT_ALIGNED_ACCESS
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+ def_bool 64BIT && !HAVE_EFFICIENT_UNALIGNED_ACCESS
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+ help
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+ Some architectures require 64 bit accesses to be 64 bit
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+ aligned, which also requires structs containing 64 bit values
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+ to be 64 bit aligned too. This includes some 32 bit
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+ architectures which can do 64 bit accesses, as well as 64 bit
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+ architectures without unaligned access.
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+
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+ This symbol should be selected by an architecture if 64 bit
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+ accesses are required to be 64 bit aligned in this way even
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+ though it is not a 64 bit architecture.
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+
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+ See Documentation/unaligned-memory-access.txt for more
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+ information on the topic of unaligned memory accesses.
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+
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+config HAVE_EFFICIENT_UNALIGNED_ACCESS
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+ bool
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+ help
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+ Some architectures are unable to perform unaligned accesses
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+ without the use of get_unaligned/put_unaligned. Others are
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+ unable to perform such accesses efficiently (e.g. trap on
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+ unaligned access and require fixing it up in the exception
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+ handler.)
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+
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+ This symbol should be selected by an architecture if it can
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+ perform unaligned accesses efficiently to allow different
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+ code paths to be selected for these cases. Some network
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+ drivers, for example, could opt to not fix up alignment
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+ problems with received packets if doing so would not help
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+ much.
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+
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+ See Documentation/unaligned-memory-access.txt for more
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+ information on the topic of unaligned memory accesses.
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+
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+config ARCH_USE_BUILTIN_BSWAP
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+ bool
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+ help
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+ Modern versions of GCC (since 4.4) have builtin functions
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+ for handling byte-swapping. Using these, instead of the old
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+ inline assembler that the architecture code provides in the
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+ __arch_bswapXX() macros, allows the compiler to see what's
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+ happening and offers more opportunity for optimisation. In
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+ particular, the compiler will be able to combine the byteswap
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+ with a nearby load or store and use load-and-swap or
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+ store-and-swap instructions if the architecture has them. It
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+ should almost *never* result in code which is worse than the
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+ hand-coded assembler in <asm/swab.h>. But just in case it
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+ does, the use of the builtins is optional.
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+
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+ Any architecture with load-and-swap or store-and-swap
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+ instructions should set this. And it shouldn't hurt to set it
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+ on architectures that don't have such instructions.
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+
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+config KRETPROBES
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+ def_bool y
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+ depends on KPROBES && HAVE_KRETPROBES
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+
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+config USER_RETURN_NOTIFIER
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+ bool
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+ depends on HAVE_USER_RETURN_NOTIFIER
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+ help
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+ Provide a kernel-internal notification when a cpu is about to
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+ switch to user mode.
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+
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+config HAVE_IOREMAP_PROT
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+ bool
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+
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+config HAVE_KPROBES
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+ bool
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+
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+config HAVE_KRETPROBES
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+ bool
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+
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+config HAVE_OPTPROBES
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+ bool
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+
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+config HAVE_KPROBES_ON_FTRACE
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+ bool
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+
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+config HAVE_NMI
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+ bool
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+
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+config HAVE_NMI_WATCHDOG
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+ depends on HAVE_NMI
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+ bool
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+#
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+# An arch should select this if it provides all these things:
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+#
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+# task_pt_regs() in asm/processor.h or asm/ptrace.h
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+# arch_has_single_step() if there is hardware single-step support
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+# arch_has_block_step() if there is hardware block-step support
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+# asm/syscall.h supplying asm-generic/syscall.h interface
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+# linux/regset.h user_regset interfaces
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+# CORE_DUMP_USE_REGSET #define'd in linux/elf.h
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+# TIF_SYSCALL_TRACE calls tracehook_report_syscall_{entry,exit}
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+# TIF_NOTIFY_RESUME calls tracehook_notify_resume()
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+# signal delivery calls tracehook_signal_handler()
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+#
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+config HAVE_ARCH_TRACEHOOK
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+ bool
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+
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+config HAVE_DMA_CONTIGUOUS
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+ bool
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+
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+config GENERIC_SMP_IDLE_THREAD
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+ bool
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+
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+config GENERIC_IDLE_POLL_SETUP
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+ bool
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+
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+# Select if arch init_task initializer is different to init/init_task.c
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+config ARCH_INIT_TASK
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+ bool
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+
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+# Select if arch has its private alloc_task_struct() function
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+config ARCH_TASK_STRUCT_ALLOCATOR
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+ bool
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+
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+# Select if arch has its private alloc_thread_stack() function
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+config ARCH_THREAD_STACK_ALLOCATOR
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+ bool
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+
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+# Select if arch wants to size task_struct dynamically via arch_task_struct_size:
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+config ARCH_WANTS_DYNAMIC_TASK_STRUCT
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+ bool
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+
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+config HAVE_REGS_AND_STACK_ACCESS_API
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+ bool
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+ help
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+ This symbol should be selected by an architecure if it supports
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+ the API needed to access registers and stack entries from pt_regs,
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+ declared in asm/ptrace.h
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+ For example the kprobes-based event tracer needs this API.
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+
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+config HAVE_CLK
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+ bool
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+ help
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+ The <linux/clk.h> calls support software clock gating and
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+ thus are a key power management tool on many systems.
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+
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+config HAVE_DMA_API_DEBUG
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+ bool
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+
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+config HAVE_HW_BREAKPOINT
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+ bool
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+ depends on PERF_EVENTS
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+
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+config HAVE_MIXED_BREAKPOINTS_REGS
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+ bool
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+ depends on HAVE_HW_BREAKPOINT
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+ help
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+ Depending on the arch implementation of hardware breakpoints,
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+ some of them have separate registers for data and instruction
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+ breakpoints addresses, others have mixed registers to store
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+ them but define the access type in a control register.
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+ Select this option if your arch implements breakpoints under the
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+ latter fashion.
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+
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+config HAVE_USER_RETURN_NOTIFIER
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+ bool
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+
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+config HAVE_PERF_EVENTS_NMI
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+ bool
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+ help
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+ System hardware can generate an NMI using the perf event
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+ subsystem. Also has support for calculating CPU cycle events
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+ to determine how many clock cycles in a given period.
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+
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+config HAVE_PERF_REGS
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+ bool
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+ help
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+ Support selective register dumps for perf events. This includes
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+ bit-mapping of each registers and a unique architecture id.
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+
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+config HAVE_PERF_USER_STACK_DUMP
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+ bool
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+ help
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+ Support user stack dumps for perf event samples. This needs
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+ access to the user stack pointer which is not unified across
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+ architectures.
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+
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+config HAVE_ARCH_JUMP_LABEL
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+ bool
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+
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+config HAVE_RCU_TABLE_FREE
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+ bool
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+
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+config ARCH_HAVE_NMI_SAFE_CMPXCHG
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+ bool
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+
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+config HAVE_ALIGNED_STRUCT_PAGE
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+ bool
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+ help
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+ This makes sure that struct pages are double word aligned and that
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+ e.g. the SLUB allocator can perform double word atomic operations
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+ on a struct page for better performance. However selecting this
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+ might increase the size of a struct page by a word.
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+
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+config HAVE_CMPXCHG_LOCAL
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+ bool
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+
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+config HAVE_CMPXCHG_DOUBLE
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+ bool
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+
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+config ARCH_WANT_IPC_PARSE_VERSION
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+ bool
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+
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+config ARCH_WANT_COMPAT_IPC_PARSE_VERSION
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+ bool
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+
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+config ARCH_WANT_OLD_COMPAT_IPC
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+ select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
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+ bool
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+
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+config HAVE_ARCH_SECCOMP_FILTER
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+ bool
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+ help
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+ An arch should select this symbol if it provides all of these things:
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+ - syscall_get_arch()
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+ - syscall_get_arguments()
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+ - syscall_rollback()
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+ - syscall_set_return_value()
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+ - SIGSYS siginfo_t support
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+ - secure_computing is called from a ptrace_event()-safe context
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+ - secure_computing return value is checked and a return value of -1
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+ results in the system call being skipped immediately.
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+ - seccomp syscall wired up
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+
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+config SECCOMP_FILTER
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+ def_bool y
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+ depends on HAVE_ARCH_SECCOMP_FILTER && SECCOMP && NET
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+ help
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+ Enable tasks to build secure computing environments defined
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+ in terms of Berkeley Packet Filter programs which implement
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+ task-defined system call filtering polices.
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+
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+ See Documentation/prctl/seccomp_filter.txt for details.
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+
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+config HAVE_GCC_PLUGINS
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+ bool
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+ help
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+ An arch should select this symbol if it supports building with
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+ GCC plugins.
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+
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+menuconfig GCC_PLUGINS
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+ bool "GCC plugins"
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+ depends on HAVE_GCC_PLUGINS
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+ depends on !COMPILE_TEST
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+ help
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+ GCC plugins are loadable modules that provide extra features to the
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+ compiler. They are useful for runtime instrumentation and static analysis.
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+
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+ See Documentation/gcc-plugins.txt for details.
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+
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+config GCC_PLUGIN_CYC_COMPLEXITY
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+ bool "Compute the cyclomatic complexity of a function"
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+ depends on GCC_PLUGINS
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+ help
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+ The complexity M of a function's control flow graph is defined as:
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+ M = E - N + 2P
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+ where
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+
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+ E = the number of edges
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+ N = the number of nodes
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+ P = the number of connected components (exit nodes).
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+
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+config GCC_PLUGIN_SANCOV
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+ bool
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+ depends on GCC_PLUGINS
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+ help
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+ This plugin inserts a __sanitizer_cov_trace_pc() call at the start of
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+ basic blocks. It supports all gcc versions with plugin support (from
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+ gcc-4.5 on). It is based on the commit "Add fuzzing coverage support"
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+ by Dmitry Vyukov <dvyukov@google.com>.
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+
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+config GCC_PLUGIN_LATENT_ENTROPY
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+ bool "Generate some entropy during boot and runtime"
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+ depends on GCC_PLUGINS
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+ help
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+ By saying Y here the kernel will instrument some kernel code to
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+ extract some entropy from both original and artificially created
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+ program state. This will help especially embedded systems where
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+ there is little 'natural' source of entropy normally. The cost
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+ is some slowdown of the boot process (about 0.5%) and fork and
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+ irq processing.
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+
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+ Note that entropy extracted this way is not cryptographically
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+ secure!
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+
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+ This plugin was ported from grsecurity/PaX. More information at:
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+ * https://grsecurity.net/
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+ * https://pax.grsecurity.net/
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+
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+config HAVE_CC_STACKPROTECTOR
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+ bool
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+ help
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+ An arch should select this symbol if:
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+ - its compiler supports the -fstack-protector option
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+ - it has implemented a stack canary (e.g. __stack_chk_guard)
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+
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+config CC_STACKPROTECTOR
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+ def_bool n
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+ help
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+ Set when a stack-protector mode is enabled, so that the build
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+ can enable kernel-side support for the GCC feature.
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+
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+choice
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+ prompt "Stack Protector buffer overflow detection"
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+ depends on HAVE_CC_STACKPROTECTOR
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+ default CC_STACKPROTECTOR_NONE
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+ help
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+ This option turns on the "stack-protector" GCC feature. This
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+ feature puts, at the beginning of functions, a canary value on
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+ the stack just before the return address, and validates
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+ the value just before actually returning. Stack based buffer
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+ overflows (that need to overwrite this return address) now also
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+ overwrite the canary, which gets detected and the attack is then
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+ neutralized via a kernel panic.
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+
|
|
|
+config CC_STACKPROTECTOR_NONE
|
|
|
+ bool "None"
|
|
|
+ help
|
|
|
+ Disable "stack-protector" GCC feature.
|
|
|
+
|
|
|
+config CC_STACKPROTECTOR_REGULAR
|
|
|
+ bool "Regular"
|
|
|
+ select CC_STACKPROTECTOR
|
|
|
+ help
|
|
|
+ Functions will have the stack-protector canary logic added if they
|
|
|
+ have an 8-byte or larger character array on the stack.
|
|
|
+
|
|
|
+ This feature requires gcc version 4.2 or above, or a distribution
|
|
|
+ gcc with the feature backported ("-fstack-protector").
|
|
|
+
|
|
|
+ On an x86 "defconfig" build, this feature adds canary checks to
|
|
|
+ about 3% of all kernel functions, which increases kernel code size
|
|
|
+ by about 0.3%.
|
|
|
+
|
|
|
+config CC_STACKPROTECTOR_STRONG
|
|
|
+ bool "Strong"
|
|
|
+ select CC_STACKPROTECTOR
|
|
|
+ help
|
|
|
+ Functions will have the stack-protector canary logic added in any
|
|
|
+ of the following conditions:
|
|
|
+
|
|
|
+ - local variable's address used as part of the right hand side of an
|
|
|
+ assignment or function argument
|
|
|
+ - local variable is an array (or union containing an array),
|
|
|
+ regardless of array type or length
|
|
|
+ - uses register local variables
|
|
|
+
|
|
|
+ This feature requires gcc version 4.9 or above, or a distribution
|
|
|
+ gcc with the feature backported ("-fstack-protector-strong").
|
|
|
+
|
|
|
+ On an x86 "defconfig" build, this feature adds canary checks to
|
|
|
+ about 20% of all kernel functions, which increases the kernel code
|
|
|
+ size by about 2%.
|
|
|
+
|
|
|
+endchoice
|
|
|
+
|
|
|
+config THIN_ARCHIVES
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ Select this if the architecture wants to use thin archives
|
|
|
+ instead of ld -r to create the built-in.o files.
|
|
|
+
|
|
|
+config LD_DEAD_CODE_DATA_ELIMINATION
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ Select this if the architecture wants to do dead code and
|
|
|
+ data elimination with the linker by compiling with
|
|
|
+ -ffunction-sections -fdata-sections and linking with
|
|
|
+ --gc-sections.
|
|
|
+
|
|
|
+ This requires that the arch annotates or otherwise protects
|
|
|
+ its external entry points from being discarded. Linker scripts
|
|
|
+ must also merge .text.*, .data.*, and .bss.* correctly into
|
|
|
+ output sections. Care must be taken not to pull in unrelated
|
|
|
+ sections (e.g., '.text.init'). Typically '.' in section names
|
|
|
+ is used to distinguish them from label names / C identifiers.
|
|
|
+
|
|
|
+config LTO
|
|
|
+ def_bool n
|
|
|
+
|
|
|
+config ARCH_SUPPORTS_LTO_CLANG
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ An architecture should select this option it supports:
|
|
|
+ - compiling with clang,
|
|
|
+ - compiling inline assembly with clang's integrated assembler,
|
|
|
+ - and linking with either lld or GNU gold w/ LLVMgold.
|
|
|
+
|
|
|
+choice
|
|
|
+ prompt "Link-Time Optimization (LTO) (EXPERIMENTAL)"
|
|
|
+ default LTO_NONE
|
|
|
+ help
|
|
|
+ This option turns on Link-Time Optimization (LTO).
|
|
|
+
|
|
|
+config LTO_NONE
|
|
|
+ bool "None"
|
|
|
+
|
|
|
+config LTO_CLANG
|
|
|
+ bool "Use clang Link Time Optimization (LTO) (EXPERIMENTAL)"
|
|
|
+ depends on ARCH_SUPPORTS_LTO_CLANG
|
|
|
+ depends on !FTRACE_MCOUNT_RECORD || HAVE_C_RECORDMCOUNT
|
|
|
+ select LTO
|
|
|
+ select THIN_ARCHIVES
|
|
|
+ select LD_DEAD_CODE_DATA_ELIMINATION
|
|
|
+ help
|
|
|
+ This option enables clang's Link Time Optimization (LTO), which allows
|
|
|
+ the compiler to optimize the kernel globally at link time. If you
|
|
|
+ enable this option, the compiler generates LLVM IR instead of object
|
|
|
+ files, and the actual compilation from IR occurs at the LTO link step,
|
|
|
+ which may take several minutes.
|
|
|
+
|
|
|
+ If you select this option, you must compile the kernel with clang >=
|
|
|
+ 5.0 (make CC=clang) and GNU gold from binutils >= 2.27, and have the
|
|
|
+ LLVMgold plug-in in LD_LIBRARY_PATH.
|
|
|
+
|
|
|
+endchoice
|
|
|
+
|
|
|
+config CFI
|
|
|
+ bool
|
|
|
+
|
|
|
+config CFI_PERMISSIVE
|
|
|
+ bool "Use CFI in permissive mode"
|
|
|
+ depends on CFI
|
|
|
+ help
|
|
|
+ When selected, Control Flow Integrity (CFI) violations result in a
|
|
|
+ warning instead of a kernel panic. This option is useful for finding
|
|
|
+ CFI violations in drivers during development.
|
|
|
+
|
|
|
+config CFI_CLANG
|
|
|
+ bool "Use clang Control Flow Integrity (CFI) (EXPERIMENTAL)"
|
|
|
+ depends on LTO_CLANG
|
|
|
+ depends on KALLSYMS
|
|
|
+ select CFI
|
|
|
+ help
|
|
|
+ This option enables clang Control Flow Integrity (CFI), which adds
|
|
|
+ runtime checking for indirect function calls.
|
|
|
+
|
|
|
+config CFI_CLANG_SHADOW
|
|
|
+ bool "Use CFI shadow to speed up cross-module checks"
|
|
|
+ default y
|
|
|
+ depends on CFI_CLANG
|
|
|
+ help
|
|
|
+ If you select this option, the kernel builds a fast look-up table of
|
|
|
+ CFI check functions in loaded modules to reduce overhead.
|
|
|
+
|
|
|
+config HAVE_ARCH_WITHIN_STACK_FRAMES
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ An architecture should select this if it can walk the kernel stack
|
|
|
+ frames to determine if an object is part of either the arguments
|
|
|
+ or local variables (i.e. that it excludes saved return addresses,
|
|
|
+ and similar) by implementing an inline arch_within_stack_frames(),
|
|
|
+ which is used by CONFIG_HARDENED_USERCOPY.
|
|
|
+
|
|
|
+config HAVE_CONTEXT_TRACKING
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ Provide kernel/user boundaries probes necessary for subsystems
|
|
|
+ that need it, such as userspace RCU extended quiescent state.
|
|
|
+ Syscalls need to be wrapped inside user_exit()-user_enter() through
|
|
|
+ the slow path using TIF_NOHZ flag. Exceptions handlers must be
|
|
|
+ wrapped as well. Irqs are already protected inside
|
|
|
+ rcu_irq_enter/rcu_irq_exit() but preemption or signal handling on
|
|
|
+ irq exit still need to be protected.
|
|
|
+
|
|
|
+config HAVE_VIRT_CPU_ACCOUNTING
|
|
|
+ bool
|
|
|
+
|
|
|
+config HAVE_VIRT_CPU_ACCOUNTING_GEN
|
|
|
+ bool
|
|
|
+ default y if 64BIT
|
|
|
+ help
|
|
|
+ With VIRT_CPU_ACCOUNTING_GEN, cputime_t becomes 64-bit.
|
|
|
+ Before enabling this option, arch code must be audited
|
|
|
+ to ensure there are no races in concurrent read/write of
|
|
|
+ cputime_t. For example, reading/writing 64-bit cputime_t on
|
|
|
+ some 32-bit arches may require multiple accesses, so proper
|
|
|
+ locking is needed to protect against concurrent accesses.
|
|
|
+
|
|
|
+
|
|
|
+config HAVE_IRQ_TIME_ACCOUNTING
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ Archs need to ensure they use a high enough resolution clock to
|
|
|
+ support irq time accounting and then call enable_sched_clock_irqtime().
|
|
|
+
|
|
|
+config HAVE_ARCH_TRANSPARENT_HUGEPAGE
|
|
|
+ bool
|
|
|
+
|
|
|
+config HAVE_ARCH_HUGE_VMAP
|
|
|
+ bool
|
|
|
+
|
|
|
+config HAVE_ARCH_SOFT_DIRTY
|
|
|
+ bool
|
|
|
+
|
|
|
+config HAVE_MOD_ARCH_SPECIFIC
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ The arch uses struct mod_arch_specific to store data. Many arches
|
|
|
+ just need a simple module loader without arch specific data - those
|
|
|
+ should not enable this.
|
|
|
+
|
|
|
+config MODULES_USE_ELF_RELA
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ Modules only use ELF RELA relocations. Modules with ELF REL
|
|
|
+ relocations will give an error.
|
|
|
+
|
|
|
+config MODULES_USE_ELF_REL
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ Modules only use ELF REL relocations. Modules with ELF RELA
|
|
|
+ relocations will give an error.
|
|
|
+
|
|
|
+config HAVE_UNDERSCORE_SYMBOL_PREFIX
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ Some architectures generate an _ in front of C symbols; things like
|
|
|
+ module loading and assembly files need to know about this.
|
|
|
+
|
|
|
+config HAVE_IRQ_EXIT_ON_IRQ_STACK
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ Architecture doesn't only execute the irq handler on the irq stack
|
|
|
+ but also irq_exit(). This way we can process softirqs on this irq
|
|
|
+ stack instead of switching to a new one when we call __do_softirq()
|
|
|
+ in the end of an hardirq.
|
|
|
+ This spares a stack switch and improves cache usage on softirq
|
|
|
+ processing.
|
|
|
+
|
|
|
+config PGTABLE_LEVELS
|
|
|
+ int
|
|
|
+ default 2
|
|
|
+
|
|
|
+config ARCH_HAS_ELF_RANDOMIZE
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ An architecture supports choosing randomized locations for
|
|
|
+ stack, mmap, brk, and ET_DYN. Defined functions:
|
|
|
+ - arch_mmap_rnd()
|
|
|
+ - arch_randomize_brk()
|
|
|
+
|
|
|
+config HAVE_ARCH_MMAP_RND_BITS
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ An arch should select this symbol if it supports setting a variable
|
|
|
+ number of bits for use in establishing the base address for mmap
|
|
|
+ allocations, has MMU enabled and provides values for both:
|
|
|
+ - ARCH_MMAP_RND_BITS_MIN
|
|
|
+ - ARCH_MMAP_RND_BITS_MAX
|
|
|
+
|
|
|
+config HAVE_EXIT_THREAD
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ An architecture implements exit_thread.
|
|
|
+
|
|
|
+config ARCH_MMAP_RND_BITS_MIN
|
|
|
+ int
|
|
|
+
|
|
|
+config ARCH_MMAP_RND_BITS_MAX
|
|
|
+ int
|
|
|
+
|
|
|
+config ARCH_MMAP_RND_BITS_DEFAULT
|
|
|
+ int
|
|
|
+
|
|
|
+config ARCH_MMAP_RND_BITS
|
|
|
+ int "Number of bits to use for ASLR of mmap base address" if EXPERT
|
|
|
+ range ARCH_MMAP_RND_BITS_MIN ARCH_MMAP_RND_BITS_MAX
|
|
|
+ default ARCH_MMAP_RND_BITS_DEFAULT if ARCH_MMAP_RND_BITS_DEFAULT
|
|
|
+ default ARCH_MMAP_RND_BITS_MIN
|
|
|
+ depends on HAVE_ARCH_MMAP_RND_BITS
|
|
|
+ help
|
|
|
+ This value can be used to select the number of bits to use to
|
|
|
+ determine the random offset to the base address of vma regions
|
|
|
+ resulting from mmap allocations. This value will be bounded
|
|
|
+ by the architecture's minimum and maximum supported values.
|
|
|
+
|
|
|
+ This value can be changed after boot using the
|
|
|
+ /proc/sys/vm/mmap_rnd_bits tunable
|
|
|
+
|
|
|
+config HAVE_ARCH_MMAP_RND_COMPAT_BITS
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ An arch should select this symbol if it supports running applications
|
|
|
+ in compatibility mode, supports setting a variable number of bits for
|
|
|
+ use in establishing the base address for mmap allocations, has MMU
|
|
|
+ enabled and provides values for both:
|
|
|
+ - ARCH_MMAP_RND_COMPAT_BITS_MIN
|
|
|
+ - ARCH_MMAP_RND_COMPAT_BITS_MAX
|
|
|
+
|
|
|
+config ARCH_MMAP_RND_COMPAT_BITS_MIN
|
|
|
+ int
|
|
|
+
|
|
|
+config ARCH_MMAP_RND_COMPAT_BITS_MAX
|
|
|
+ int
|
|
|
+
|
|
|
+config ARCH_MMAP_RND_COMPAT_BITS_DEFAULT
|
|
|
+ int
|
|
|
+
|
|
|
+config ARCH_MMAP_RND_COMPAT_BITS
|
|
|
+ int "Number of bits to use for ASLR of mmap base address for compatible applications" if EXPERT
|
|
|
+ range ARCH_MMAP_RND_COMPAT_BITS_MIN ARCH_MMAP_RND_COMPAT_BITS_MAX
|
|
|
+ default ARCH_MMAP_RND_COMPAT_BITS_DEFAULT if ARCH_MMAP_RND_COMPAT_BITS_DEFAULT
|
|
|
+ default ARCH_MMAP_RND_COMPAT_BITS_MIN
|
|
|
+ depends on HAVE_ARCH_MMAP_RND_COMPAT_BITS
|
|
|
+ help
|
|
|
+ This value can be used to select the number of bits to use to
|
|
|
+ determine the random offset to the base address of vma regions
|
|
|
+ resulting from mmap allocations for compatible applications This
|
|
|
+ value will be bounded by the architecture's minimum and maximum
|
|
|
+ supported values.
|
|
|
+
|
|
|
+ This value can be changed after boot using the
|
|
|
+ /proc/sys/vm/mmap_rnd_compat_bits tunable
|
|
|
+
|
|
|
+config HAVE_COPY_THREAD_TLS
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ Architecture provides copy_thread_tls to accept tls argument via
|
|
|
+ normal C parameter passing, rather than extracting the syscall
|
|
|
+ argument from pt_regs.
|
|
|
+
|
|
|
+config HAVE_STACK_VALIDATION
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ Architecture supports the 'objtool check' host tool command, which
|
|
|
+ performs compile-time stack metadata validation.
|
|
|
+
|
|
|
+config HAVE_ARCH_HASH
|
|
|
+ bool
|
|
|
+ default n
|
|
|
+ help
|
|
|
+ If this is set, the architecture provides an <asm/hash.h>
|
|
|
+ file which provides platform-specific implementations of some
|
|
|
+ functions in <linux/hash.h> or fs/namei.c.
|
|
|
+
|
|
|
+config ISA_BUS_API
|
|
|
+ def_bool ISA
|
|
|
+
|
|
|
+#
|
|
|
+# ABI hall of shame
|
|
|
+#
|
|
|
+config CLONE_BACKWARDS
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ Architecture has tls passed as the 4th argument of clone(2),
|
|
|
+ not the 5th one.
|
|
|
+
|
|
|
+config CLONE_BACKWARDS2
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ Architecture has the first two arguments of clone(2) swapped.
|
|
|
+
|
|
|
+config CLONE_BACKWARDS3
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ Architecture has tls passed as the 3rd argument of clone(2),
|
|
|
+ not the 5th one.
|
|
|
+
|
|
|
+config ODD_RT_SIGACTION
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ Architecture has unusual rt_sigaction(2) arguments
|
|
|
+
|
|
|
+config OLD_SIGSUSPEND
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ Architecture has old sigsuspend(2) syscall, of one-argument variety
|
|
|
+
|
|
|
+config OLD_SIGSUSPEND3
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ Even weirder antique ABI - three-argument sigsuspend(2)
|
|
|
+
|
|
|
+config OLD_SIGACTION
|
|
|
+ bool
|
|
|
+ help
|
|
|
+ Architecture has old sigaction(2) syscall. Nope, not the same
|
|
|
+ as OLD_SIGSUSPEND | OLD_SIGSUSPEND3 - alpha has sigsuspend(2),
|
|
|
+ but fairly different variant of sigaction(2), thanks to OSF/1
|
|
|
+ compatibility...
|
|
|
+
|
|
|
+config COMPAT_OLD_SIGACTION
|
|
|
+ bool
|
|
|
+
|
|
|
+config ARCH_NO_COHERENT_DMA_MMAP
|
|
|
+ bool
|
|
|
+
|
|
|
+config CPU_NO_EFFICIENT_FFS
|
|
|
+ def_bool n
|
|
|
+
|
|
|
+config HAVE_ARCH_VMAP_STACK
|
|
|
+ def_bool n
|
|
|
+ help
|
|
|
+ An arch should select this symbol if it can support kernel stacks
|
|
|
+ in vmalloc space. This means:
|
|
|
+
|
|
|
+ - vmalloc space must be large enough to hold many kernel stacks.
|
|
|
+ This may rule out many 32-bit architectures.
|
|
|
+
|
|
|
+ - Stacks in vmalloc space need to work reliably. For example, if
|
|
|
+ vmap page tables are created on demand, either this mechanism
|
|
|
+ needs to work while the stack points to a virtual address with
|
|
|
+ unpopulated page tables or arch code (switch_to() and switch_mm(),
|
|
|
+ most likely) needs to ensure that the stack's page table entries
|
|
|
+ are populated before running on a possibly unpopulated stack.
|
|
|
+
|
|
|
+ - If the stack overflows into a guard page, something reasonable
|
|
|
+ should happen. The definition of "reasonable" is flexible, but
|
|
|
+ instantly rebooting without logging anything would be unfriendly.
|
|
|
+
|
|
|
+config VMAP_STACK
|
|
|
+ default y
|
|
|
+ bool "Use a virtually-mapped stack"
|
|
|
+ depends on HAVE_ARCH_VMAP_STACK && !KASAN
|
|
|
+ ---help---
|
|
|
+ Enable this if you want the use virtually-mapped kernel stacks
|
|
|
+ with guard pages. This causes kernel stack overflows to be
|
|
|
+ caught immediately rather than causing difficult-to-diagnose
|
|
|
+ corruption.
|
|
|
+
|
|
|
+ This is presently incompatible with KASAN because KASAN expects
|
|
|
+ the stack to map directly to the KASAN shadow map using a formula
|
|
|
+ that is incorrect if the stack is in vmalloc space.
|
|
|
+
|
|
|
+source "kernel/gcov/Kconfig"
|