- In case of system crash, current state of cpu registers is saved in memory
in elf note format. So far memory for storing elf notes was being allocated
statically for NR_CPUS.
- This patch introduces dynamic allocation of memory for storing elf notes.
It uses alloc_percpu() interface. This should lead to better memory usage.
- Introduced based on Andi Kleen's and Eric W. Biederman's suggestions.
- This patch also moves memory allocation for elf notes from architecture
dependent portion to architecture independent portion. Now crash_notes is
architecture independent. The whole idea is that size of memory to be
allocated per cpu (MAX_NOTE_BYTES) can be architecture dependent and
allocation of this memory can be architecture independent.
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Merge include/asm-ppc/kexec.h and include/asm-ppc64/kexec.h.
The only thing that's really changed is that we now allocate crash_notes
properly on PPC32. It's address is exported via sysfs, so it's not correct
for it to be a pointer.
I've also removed some of the "we don't use this" comments, because they're
wrong (or perhaps were referring only to arch code).
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
The following patch prevents the crash dump helper code found within kexec
from breaking ppc which still lacks crash dump functionality.
ksysfs crash_notes attribute handling was left under CONFIG_KEXEC for
simplicity although it is not strictly kexec related.
We provide here a dummy definition for crash_notes on ppc.
Signed-off-by: Albert Herranz <albert_herranz@yahoo.es>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
o Following patch provides purely cosmetic changes and corrects CodingStyle
guide lines related certain issues like below in kexec related files
o braces for one line "if" statements, "for" loops,
o more than 80 column wide lines,
o No space after "while", "for" and "switch" key words
o Changes:
o take-2: Removed the extra tab before "case" key words.
o take-3: Put operator at the end of line and space before "*/"
Signed-off-by: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Makes kexec_crashdump() take a pt_regs * as an argument. This allows to
get exact register state at the point of the crash. If we come from direct
panic assertion NULL will be passed and the current registers saved before
crashdump.
This hooks into two places:
die(): check the conditions under which we will panic when calling
do_exit and go there directly with the pt_regs that caused the fatal
fault.
die_nmi(): If we receive an NMI lockup while in the kernel use the
pt_regs and go directly to crash_kexec(). We're probably nested up badly
at this point so this might be the only chance to escape with proper
information.
Signed-off-by: Alexander Nyberg <alexn@telia.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I have tweaked this patch slightly to handle an empty list
of pages to relocate passed to relocate_new_kernel. And
I have added ppc_md.machine_crash_shutdown. To keep up with
the changes in the generic kexec infrastructure.
From: Albert Herranz <albert_herranz@yahoo.es>
The following patch adds support for kexec on the ppc32 platform.
Non-OpenFirmware based platforms are likely to work directly without
additional changes on the kernel side. The kexec-tools userland package
may need to be slightly updated, though.
For OpenFirmware based machines, additional work is still needed on the
kernel side before kexec support is ready. Benjamin Herrenschmidt is
kindly working on that part.
In order for a ppc platform to use the kexec kernel services it must
implement some ppc_md hooks. Otherwise, kexec will be explicitly disabled,
as suggested by benh.
There are 3+1 new ppc_md hooks that a platform supporting kexec may
implement. Two of them are mandatory for kexec to work. See
include/asm-ppc/machdep.h for details.
- machine_kexec_prepare(image)
This function is called to make any arrangements to the image before it
is loaded.
This hook _MUST_ be provided by a platform in order to activate kexec
support for that platform. Otherwise, the platform is considered to not
support kexec and the kexec_load system call will fail (that makes all
existing platforms by default non-kexec'able).
- machine_kexec_cleanup(image)
This function is called to make any cleanups on image after the loaded
image data it is freed. This hook is optional. A platform may or may
not provide this hook.
- machine_kexec(image)
This function is called to perform the _actual_ kexec. This hook
_MUST_ be provided by a platform in order to activate kexec support for
that platform.
If a platform provides machine_kexec_prepare but forgets to provide
machine_kexec, a kexec will fall back to a reboot.
A ready-to-use machine_kexec_simple() generic function is provided to,
hopefully, simplify kexec adoption for embedded platforms. A platform
may call this function from its specific machine_kexec hook, like this:
void myplatform_kexec(struct kimage *image)
{
machine_kexec_simple(image);
}
- machine_shutdown()
This function is called to perform any machine specific shutdowns, not
already done by drivers. This hook is optional. A platform may or may
not provide this hook.
An example (trimmed) platform specific module for a platform supporting
kexec through the existing machine_kexec_simple follows:
/* ... */
#ifdef CONFIG_KEXEC
int myplatform_kexec_prepare(struct kimage *image)
{
/* here, we can place additional preparations
*/
return 0; /* yes, we support kexec */
}
void myplatform_kexec(struct kimage *image)
{
machine_kexec_simple(image);
}
#endif /* CONFIG_KEXEC */
/* ... */
void __init
platform_init(unsigned long r3, unsigned long r4,
unsigned long r5,
unsigned long r6, unsigned long r7)
{
/* ... */
#ifdef CONFIG_KEXEC
ppc_md.machine_kexec_prepare =
myplatform_kexec_prepare;
ppc_md.machine_kexec =
myplatform_kexec;
#endif /* CONFIG_KEXEC */
/* ... */
}
The kexec ppc kernel support has been heavily tested on the GameCube Linux
port, and, as reported in the fastboot mailing list, it has been tested too
on a Moto 82xx ppc by Rick Richardson.
Signed-off-by: Albert Herranz <albert_herranz@yahoo.es>
Signed-off-by: Eric Biederman <ebiederm@xmission.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Vivek Goyal
Michael Ellerman
Albert Herranz
Maneesh Soni
Alexander Nyberg
Eric W. Biederman