diff options
Diffstat (limited to 'arch/Kconfig')
| -rw-r--r-- | arch/Kconfig | 266 |
1 files changed, 255 insertions, 11 deletions
diff --git a/arch/Kconfig b/arch/Kconfig index 8c3d957fa8e..97ff872c7ac 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -76,10 +76,18 @@ config OPTPROBES depends on KPROBES && HAVE_OPTPROBES depends on !PREEMPT +config KPROBES_ON_FTRACE + def_bool y + depends on KPROBES && HAVE_KPROBES_ON_FTRACE + depends on DYNAMIC_FTRACE_WITH_REGS + help + If function tracer is enabled and the arch supports full + passing of pt_regs to function tracing, then kprobes can + optimize on top of function tracing. + config UPROBES - bool "Transparent user-space probes (EXPERIMENTAL)" - depends on UPROBE_EVENT && PERF_EVENTS - default n + def_bool n + select PERCPU_RWSEM help Uprobes is the user-space counterpart to kprobes: they enable instrumentation applications (such as 'perf probe') @@ -91,7 +99,21 @@ config UPROBES managed by the kernel and kept transparent to the probed application. ) - If in doubt, say "N". +config HAVE_64BIT_ALIGNED_ACCESS + def_bool 64BIT && !HAVE_EFFICIENT_UNALIGNED_ACCESS + help + Some architectures require 64 bit accesses to be 64 bit + aligned, which also requires structs containing 64 bit values + to be 64 bit aligned too. This includes some 32 bit + architectures which can do 64 bit accesses, as well as 64 bit + architectures without unaligned access. + + This symbol should be selected by an architecture if 64 bit + accesses are required to be 64 bit aligned in this way even + though it is not a 64 bit architecture. + + See Documentation/unaligned-memory-access.txt for more + information on the topic of unaligned memory accesses. config HAVE_EFFICIENT_UNALIGNED_ACCESS bool @@ -112,8 +134,24 @@ config HAVE_EFFICIENT_UNALIGNED_ACCESS See Documentation/unaligned-memory-access.txt for more information on the topic of unaligned memory accesses. -config HAVE_SYSCALL_WRAPPERS - bool +config ARCH_USE_BUILTIN_BSWAP + bool + help + Modern versions of GCC (since 4.4) have builtin functions + for handling byte-swapping. Using these, instead of the old + inline assembler that the architecture code provides in the + __arch_bswapXX() macros, allows the compiler to see what's + happening and offers more opportunity for optimisation. In + particular, the compiler will be able to combine the byteswap + with a nearby load or store and use load-and-swap or + store-and-swap instructions if the architecture has them. It + should almost *never* result in code which is worse than the + hand-coded assembler in <asm/swab.h>. But just in case it + does, the use of the builtins is optional. + + Any architecture with load-and-swap or store-and-swap + instructions should set this. And it shouldn't hurt to set it + on architectures that don't have such instructions. config KRETPROBES def_bool y @@ -138,6 +176,9 @@ config HAVE_KRETPROBES config HAVE_OPTPROBES bool +config HAVE_KPROBES_ON_FTRACE + bool + config HAVE_NMI_WATCHDOG bool # @@ -162,12 +203,12 @@ config HAVE_DMA_ATTRS config HAVE_DMA_CONTIGUOUS bool -config USE_GENERIC_SMP_HELPERS - bool - config GENERIC_SMP_IDLE_THREAD bool +config GENERIC_IDLE_POLL_SETUP + bool + # Select if arch init_task initializer is different to init/init_task.c config ARCH_INIT_TASK bool @@ -222,10 +263,20 @@ config HAVE_PERF_EVENTS_NMI subsystem. Also has support for calculating CPU cycle events to determine how many clock cycles in a given period. -config HAVE_ARCH_JUMP_LABEL +config HAVE_PERF_REGS bool + help + Support selective register dumps for perf events. This includes + bit-mapping of each registers and a unique architecture id. + +config HAVE_PERF_USER_STACK_DUMP + bool + help + Support user stack dumps for perf event samples. This needs + access to the user stack pointer which is not unified across + architectures. -config HAVE_ARCH_MUTEX_CPU_RELAX +config HAVE_ARCH_JUMP_LABEL bool config HAVE_RCU_TABLE_FREE @@ -248,7 +299,14 @@ config HAVE_CMPXCHG_LOCAL config HAVE_CMPXCHG_DOUBLE bool +config ARCH_WANT_IPC_PARSE_VERSION + bool + +config ARCH_WANT_COMPAT_IPC_PARSE_VERSION + bool + config ARCH_WANT_OLD_COMPAT_IPC + select ARCH_WANT_COMPAT_IPC_PARSE_VERSION bool config HAVE_ARCH_SECCOMP_FILTER @@ -274,4 +332,190 @@ config SECCOMP_FILTER See Documentation/prctl/seccomp_filter.txt for details. +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) + +config CC_STACKPROTECTOR + def_bool n + help + Set when a stack-protector mode is enabled, so that the build + can enable kernel-side support for the GCC feature. + +choice + prompt "Stack Protector buffer overflow detection" + depends on HAVE_CC_STACKPROTECTOR + default CC_STACKPROTECTOR_NONE + help + This option turns on the "stack-protector" GCC feature. This + feature puts, at the beginning of functions, a canary value on + the stack just before the return address, and validates + the value just before actually returning. Stack based buffer + overflows (that need to overwrite this return address) now also + 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" + 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 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_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. + +# +# 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 + source "kernel/gcov/Kconfig" |
