bool
default y
+config ZONE_DMA
+ bool
+ default y
+
config SBUS
bool
bool
default y
+config GENERIC_BUG
+ bool
+ default y
+ depends on BUG
+
config GENERIC_HWEIGHT
bool
default y
endchoice
+config PARAVIRT
+ bool "Paravirtualization support (EXPERIMENTAL)"
+ depends on EXPERIMENTAL
+ depends on !(X86_VISWS || X86_VOYAGER)
+ help
+ Paravirtualization is a way of running multiple instances of
+ Linux on the same machine, under a hypervisor. This option
+ changes the kernel so it can modify itself when it is run
+ under a hypervisor, improving performance significantly.
+ However, when run without a hypervisor the kernel is
+ theoretically slower. If in doubt, say N.
+
config ACPI_SRAT
bool
default y
choice
prompt "High Memory Support"
- default NOHIGHMEM
+ default HIGHMEM4G if !X86_NUMAQ
+ default HIGHMEM64G if X86_NUMAQ
config NOHIGHMEM
bool "off"
depends on ACPI
default n
---help---
- This enables the the kernel to boot on EFI platforms using
+ This enables the kernel to boot on EFI platforms using
system configuration information passed to it from the firmware.
This also enables the kernel to use any EFI runtime services that are
available (such as the EFI variable services).
depends on (((X86_SUMMIT || X86_GENERICARCH) && NUMA) || (X86 && EFI))
default y
-config REGPARM
- bool "Use register arguments"
- default y
- help
- Compile the kernel with -mregparm=3. This instructs gcc to use
- a more efficient function call ABI which passes the first three
- arguments of a function call via registers, which results in denser
- and faster code.
-
- If this option is disabled, then the default ABI of passing
- arguments via the stack is used.
-
- If unsure, say Y.
-
config SECCOMP
bool "Enable seccomp to safely compute untrusted bytecode"
depends on PROC_FS
config PHYSICAL_START
hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
-
- default "0x1000000" if CRASH_DUMP
default "0x100000"
help
- This gives the physical address where the kernel is loaded. Normally
- for regular kernels this value is 0x100000 (1MB). But in the case
- of kexec on panic the fail safe kernel needs to run at a different
- address than the panic-ed kernel. This option is used to set the load
- address for kernels used to capture crash dump on being kexec'ed
- after panic. The default value for crash dump kernels is
- 0x1000000 (16MB). This can also be set based on the "X" value as
+ This gives the physical address where the kernel is loaded.
+
+ If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
+ bzImage will decompress itself to above physical address and
+ run from there. Otherwise, bzImage will run from the address where
+ it has been loaded by the boot loader and will ignore above physical
+ address.
+
+ In normal kdump cases one does not have to set/change this option
+ as now bzImage can be compiled as a completely relocatable image
+ (CONFIG_RELOCATABLE=y) and be used to load and run from a different
+ address. This option is mainly useful for the folks who don't want
+ to use a bzImage for capturing the crash dump and want to use a
+ vmlinux instead. vmlinux is not relocatable hence a kernel needs
+ to be specifically compiled to run from a specific memory area
+ (normally a reserved region) and this option comes handy.
+
+ So if you are using bzImage for capturing the crash dump, leave
+ the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
+ Otherwise if you plan to use vmlinux for capturing the crash dump
+ change this value to start of the reserved region (Typically 16MB
+ 0x1000000). In other words, it can be set based on the "X" value as
specified in the "crashkernel=YM@XM" command line boot parameter
passed to the panic-ed kernel. Typically this parameter is set as
crashkernel=64M@16M. Please take a look at
Documentation/kdump/kdump.txt for more details about crash dumps.
+ Usage of bzImage for capturing the crash dump is recommended as
+ one does not have to build two kernels. Same kernel can be used
+ as production kernel and capture kernel. Above option should have
+ gone away after relocatable bzImage support is introduced. But it
+ is present because there are users out there who continue to use
+ vmlinux for dump capture. This option should go away down the
+ line.
+
+ Don't change this unless you know what you are doing.
+
+config RELOCATABLE
+ bool "Build a relocatable kernel(EXPERIMENTAL)"
+ depends on EXPERIMENTAL
+ help
+ This build a kernel image that retains relocation information
+ so it can be loaded someplace besides the default 1MB.
+ The relocations tend to the kernel binary about 10% larger,
+ but are discarded at runtime.
+
+ One use is for the kexec on panic case where the recovery kernel
+ must live at a different physical address than the primary
+ kernel.
+
+config PHYSICAL_ALIGN
+ hex "Alignment value to which kernel should be aligned"
+ default "0x100000"
+ range 0x2000 0x400000
+ help
+ This value puts the alignment restrictions on physical address
+ where kernel is loaded and run from. Kernel is compiled for an
+ address which meets above alignment restriction.
+
+ If bootloader loads the kernel at a non-aligned address and
+ CONFIG_RELOCATABLE is set, kernel will move itself to nearest
+ address aligned to above value and run from there.
+
+ If bootloader loads the kernel at a non-aligned address and
+ CONFIG_RELOCATABLE is not set, kernel will ignore the run time
+ load address and decompress itself to the address it has been
+ compiled for and run from there. The address for which kernel is
+ compiled already meets above alignment restrictions. Hence the
+ end result is that kernel runs from a physical address meeting
+ above alignment restrictions.
+
Don't change this unless you know what you are doing.
config HOTPLUG_CPU
config KPROBES
bool "Kprobes (EXPERIMENTAL)"
- depends on EXPERIMENTAL && MODULES
+ depends on KALLSYMS && EXPERIMENTAL && MODULES
help
Kprobes allows you to trap at almost any kernel address and
execute a callback function. register_kprobe() establishes
projects / linux-drm-fsl-dcu.git / blobdiff