[PATCH] kexec: change CONFIG_PHYSICAL_START dependency
I have heard some complaints about people not finding CONFIG_CRASH_DUMP
option and also some objections about its dependency on CONFIG_EMBEDDED.
The following patch ends that dependency. I thought of hiding it under
CONFIG_KEXEC, but CONFIG_PHYSICAL_START could also be used for some reasons
other than kexec/kdump and hence left it visible. I will also update the
documentation accordingly.
o Following patch removes the config dependency of CONFIG_PHYSICAL_START
on CONFIG_EMBEDDED. The reason being CONFIG_CRASH_DUMP option for
kdump needs CONFIG_PHYSICAL_START which makes CONFIG_CRASH_DUMP depend
on CONFIG_EMBEDDED. It is not always obvious for kdump users to choose
CONFIG_EMBEDDED.
o It also shifts the palce where this option appears, to make it closer
to kexec and kdump options.
Signed-off-by: Maneesh Soni <maneesh@in.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Haren Myneni <haren@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/i386/Kconfig b/arch/i386/Kconfig
index d849c68..554ce3f 100644
--- a/arch/i386/Kconfig
+++ b/arch/i386/Kconfig
@@ -645,17 +645,6 @@
source kernel/Kconfig.hz
-config PHYSICAL_START
- hex "Physical address where the kernel is loaded" if EMBEDDED
- default "0x100000"
- help
- This gives the physical address where the kernel is loaded.
- Primarily used in the case of kexec on panic where the
- fail safe kernel needs to run at a different address than
- the panic-ed kernel.
-
- Don't change this unless you know what you are doing.
-
config KEXEC
bool "kexec system call (EXPERIMENTAL)"
depends on EXPERIMENTAL
@@ -675,11 +664,31 @@
config CRASH_DUMP
bool "kernel crash dumps (EXPERIMENTAL)"
- depends on EMBEDDED
depends on EXPERIMENTAL
depends on HIGHMEM
help
Generate crash dump after being started by kexec.
+
+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
+ 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.
+
+ Don't change this unless you know what you are doing.
+
endmenu