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authorDavid S. Miller <davem@davemloft.net>2013-08-03 21:36:46 -0700
committerDavid S. Miller <davem@davemloft.net>2013-08-03 21:36:46 -0700
commit0e76a3a587fc7abda2badf249053b427baad255e (patch)
tree646a1da67dc25654552028225ca4b7a0a8043cc9 /arch/arm/mm/Kconfig
parentfba3679d34511c42bf452e89dda457a1219eb43a (diff)
parent72a67a94bcba71a5fddd6b3596a20604d2b5dcd6 (diff)
downloadlinux-next-0e76a3a587fc7abda2badf249053b427baad255e.tar.gz
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Merge net into net-next to setup some infrastructure Eric Dumazet needs for usbnet changes. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'arch/arm/mm/Kconfig')
-rw-r--r--arch/arm/mm/Kconfig34
1 files changed, 34 insertions, 0 deletions
diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig
index 6cacdc8dd654..db5c2cab8fda 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