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-rw-r--r--arch/x86/Kconfig118
1 files changed, 71 insertions, 47 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 0952ecd60eca..cd18b8393400 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -125,6 +125,7 @@ config X86
select RTC_LIB
select HAVE_DEBUG_STACKOVERFLOW
select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
+ select HAVE_CC_STACKPROTECTOR
config INSTRUCTION_DECODER
def_bool y
@@ -438,42 +439,26 @@ config X86_INTEL_CE
This option compiles in support for the CE4100 SOC for settop
boxes and media devices.
-config X86_WANT_INTEL_MID
+config X86_INTEL_MID
bool "Intel MID platform support"
depends on X86_32
depends on X86_EXTENDED_PLATFORM
- ---help---
- Select to build a kernel capable of supporting Intel MID platform
- systems which do not have the PCI legacy interfaces (Moorestown,
- Medfield). If you are building for a PC class system say N here.
-
-if X86_WANT_INTEL_MID
-
-config X86_INTEL_MID
- bool
-
-config X86_MDFLD
- bool "Medfield MID platform"
depends on PCI
depends on PCI_GOANY
depends on X86_IO_APIC
- select X86_INTEL_MID
select SFI
+ select I2C
select DW_APB_TIMER
select APB_TIMER
- select I2C
- select SPI
select INTEL_SCU_IPC
- select X86_PLATFORM_DEVICES
select MFD_INTEL_MSIC
---help---
- Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin
- Internet Device(MID) platform.
- Unlike standard x86 PCs, Medfield does not have many legacy devices
- nor standard legacy replacement devices/features. e.g. Medfield does
- not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
+ Select to build a kernel capable of supporting Intel MID (Mobile
+ Internet Device) platform systems which do not have the PCI legacy
+ interfaces. If you are building for a PC class system say N here.
-endif
+ Intel MID platforms are based on an Intel processor and chipset which
+ consume less power than most of the x86 derivatives.
config X86_INTEL_LPSS
bool "Intel Low Power Subsystem Support"
@@ -1080,10 +1065,6 @@ config MICROCODE_OLD_INTERFACE
def_bool y
depends on MICROCODE
-config MICROCODE_INTEL_LIB
- def_bool y
- depends on MICROCODE_INTEL
-
config MICROCODE_INTEL_EARLY
def_bool n
@@ -1617,22 +1598,6 @@ config SECCOMP
If unsure, say Y. Only embedded should say N here.
-config CC_STACKPROTECTOR
- bool "Enable -fstack-protector buffer overflow detection"
- ---help---
- This option turns on the -fstack-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.
-
- This feature requires gcc version 4.2 or above, or a distribution
- gcc with the feature backported. Older versions are automatically
- detected and for those versions, this configuration option is
- ignored. (and a warning is printed during bootup)
-
source kernel/Kconfig.hz
config KEXEC
@@ -1728,16 +1693,67 @@ config RELOCATABLE
Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
it has been loaded at and the compile time physical address
- (CONFIG_PHYSICAL_START) is ignored.
+ (CONFIG_PHYSICAL_START) is used as the minimum location.
-# Relocation on x86-32 needs some additional build support
+config RANDOMIZE_BASE
+ bool "Randomize the address of the kernel image"
+ depends on RELOCATABLE
+ depends on !HIBERNATION
+ default n
+ ---help---
+ Randomizes the physical and virtual address at which the
+ kernel image is decompressed, as a security feature that
+ deters exploit attempts relying on knowledge of the location
+ of kernel internals.
+
+ Entropy is generated using the RDRAND instruction if it is
+ supported. If RDTSC is supported, it is used as well. If
+ neither RDRAND nor RDTSC are supported, then randomness is
+ read from the i8254 timer.
+
+ The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
+ and aligned according to PHYSICAL_ALIGN. Since the kernel is
+ built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
+ minimum of 2MiB, only 10 bits of entropy is theoretically
+ possible. At best, due to page table layouts, 64-bit can use
+ 9 bits of entropy and 32-bit uses 8 bits.
+
+ If unsure, say N.
+
+config RANDOMIZE_BASE_MAX_OFFSET
+ hex "Maximum kASLR offset allowed" if EXPERT
+ depends on RANDOMIZE_BASE
+ range 0x0 0x20000000 if X86_32
+ default "0x20000000" if X86_32
+ range 0x0 0x40000000 if X86_64
+ default "0x40000000" if X86_64
+ ---help---
+ The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
+ memory is used to determine the maximal offset in bytes that will
+ be applied to the kernel when kernel Address Space Layout
+ Randomization (kASLR) is active. This must be a multiple of
+ PHYSICAL_ALIGN.
+
+ On 32-bit this is limited to 512MiB by page table layouts. The
+ default is 512MiB.
+
+ On 64-bit this is limited by how the kernel fixmap page table is
+ positioned, so this cannot be larger than 1GiB currently. Without
+ RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
+ and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
+ modules area will shrink to compensate, up to the current maximum
+ 1GiB to 1GiB split. The default is 1GiB.
+
+ If unsure, leave at the default value.
+
+# Relocation on x86 needs some additional build support
config X86_NEED_RELOCS
def_bool y
- depends on X86_32 && RELOCATABLE
+ depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
config PHYSICAL_ALIGN
hex "Alignment value to which kernel should be aligned"
- default "0x1000000"
+ default "0x200000"
range 0x2000 0x1000000 if X86_32
range 0x200000 0x1000000 if X86_64
---help---
@@ -2393,6 +2409,14 @@ config X86_DMA_REMAP
bool
depends on STA2X11
+config IOSF_MBI
+ bool
+ depends on PCI
+ ---help---
+ To be selected by modules requiring access to the Intel OnChip System
+ Fabric (IOSF) Sideband MailBox Interface (MBI). For MBI platforms
+ enumerable by PCI.
+
source "net/Kconfig"
source "drivers/Kconfig"
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