diff options
author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-08-18 20:40:33 -0700 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-08-18 20:40:33 -0700 |
commit | 5bc0b123dcb2bb65b0b1ec57e591459dcf583d3d (patch) | |
tree | 6ee79d18fd716755d49d18c465c1b25fabc43597 /arch/arm/mm/Kconfig | |
parent | eefbc594abbb1b7e6e7eeadb65ae7c7538474210 (diff) | |
parent | b36f4be3de1b123d8601de062e7dbfc904f305fb (diff) |
Merge 3.11-rc6 into char-misc-next
We want these fixes in this tree.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/arm/mm/Kconfig')
-rw-r--r-- | arch/arm/mm/Kconfig | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig index 6cacdc8dd65..db5c2cab8fd 100644 --- a/arch/arm/mm/Kconfig +++ b/arch/arm/mm/Kconfig @@ -421,24 +421,28 @@ config CPU_32v3 select CPU_USE_DOMAINS if MMU select NEEDS_SYSCALL_FOR_CMPXCHG if SMP select TLS_REG_EMUL if SMP || !MMU + select NEED_KUSER_HELPERS config CPU_32v4 bool select CPU_USE_DOMAINS if MMU select NEEDS_SYSCALL_FOR_CMPXCHG if SMP select TLS_REG_EMUL if SMP || !MMU + select NEED_KUSER_HELPERS config CPU_32v4T bool select CPU_USE_DOMAINS if MMU select NEEDS_SYSCALL_FOR_CMPXCHG if SMP select TLS_REG_EMUL if SMP || !MMU + select NEED_KUSER_HELPERS config CPU_32v5 bool select CPU_USE_DOMAINS if MMU select NEEDS_SYSCALL_FOR_CMPXCHG if SMP select TLS_REG_EMUL if SMP || !MMU + select NEED_KUSER_HELPERS config CPU_32v6 bool @@ -776,6 +780,7 @@ config CPU_BPREDICT_DISABLE config TLS_REG_EMUL bool + select NEED_KUSER_HELPERS help An SMP system using a pre-ARMv6 processor (there are apparently a few prototypes like that in existence) and therefore access to @@ -783,11 +788,40 @@ config TLS_REG_EMUL config NEEDS_SYSCALL_FOR_CMPXCHG bool + select NEED_KUSER_HELPERS help SMP on a pre-ARMv6 processor? Well OK then. Forget about fast user space cmpxchg support. It is just not possible. +config NEED_KUSER_HELPERS + bool + +config KUSER_HELPERS + bool "Enable kuser helpers in vector page" if !NEED_KUSER_HELPERS + default y + help + Warning: disabling this option may break user programs. + + Provide kuser helpers in the vector page. The kernel provides + helper code to userspace in read only form at a fixed location + in the high vector page to allow userspace to be independent of + the CPU type fitted to the system. This permits binaries to be + run on ARMv4 through to ARMv7 without modification. + + However, the fixed address nature of these helpers can be used + by ROP (return orientated programming) authors when creating + exploits. + + If all of the binaries and libraries which run on your platform + are built specifically for your platform, and make no use of + these helpers, then you can turn this option off. However, + when such an binary or library is run, it will receive a SIGILL + signal, which will terminate the program. + + Say N here only if you are absolutely certain that you do not + need these helpers; otherwise, the safe option is to say Y. + config DMA_CACHE_RWFO bool "Enable read/write for ownership DMA cache maintenance" depends on CPU_V6K && SMP |