Commit Graph

16 Commits

Author SHA1 Message Date
Mohan Kumar M 54622f10a6 powerpc: Support for relocatable kdump kernel
This adds relocatable kernel support for kdump. With this one can
use the same regular kernel to capture the kdump. A signature (0xfeed1234)
is passed in r6 from panic code to the next kernel through kexec_sequence
and purgatory code. The signature is used to differentiate between
kdump kernel and non-kdump kernels.

The purgatory code compares the signature and sets the __kdump_flag in
head_64.S.  During the boot up, kernel code checks __kdump_flag and if it
is set, the kernel will behave as relocatable kdump kernel. This kernel
will boot at the address where it was loaded by kexec-tools ie. at the
address reserved through crashkernel boot parameter.

CONFIG_CRASH_DUMP depends on CONFIG_RELOCATABLE option to build kdump
kernel as relocatable. So the same kernel can be used as production and
kdump kernel.

This patch incorporates the changes suggested by Paul Mackerras to avoid
GOT use and to avoid two copies of the code.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Mohan Kumar M <mohan@in.ibm.com>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-10-22 15:01:22 +11:00
Vivek Goyal 57cac4d188 kdump: make elfcorehdr_addr independent of CONFIG_PROC_VMCORE
o elfcorehdr_addr is used by not only the code under CONFIG_PROC_VMCORE
  but also by the code which is not inside CONFIG_PROC_VMCORE.  For
  example, is_kdump_kernel() is used by powerpc code to determine if
  kernel is booting after a panic then use previous kernel's TCE table.
  So even if CONFIG_PROC_VMCORE is not set in second kernel, one should be
  able to correctly determine that we are booting after a panic and setup
  calgary iommu accordingly.

o So remove the assumption that elfcorehdr_addr is under
  CONFIG_PROC_VMCORE.

o Move definition of elfcorehdr_addr to arch dependent crash files.
  (Unfortunately crash dump does not have an arch independent file
  otherwise that would have been the best place).

o kexec.c is not the right place as one can Have CRASH_DUMP enabled in
  second kernel without KEXEC being enabled.

o I don't see sh setup code parsing the command line for
  elfcorehdr_addr.  I am wondering how does vmcore interface work on sh.
  Anyway, I am atleast defining elfcoredhr_addr so that compilation is not
  broken on sh.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Simon Horman <horms@verge.net.au>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 08:52:39 -07:00
Michael Ellerman 7230ced492 powerpc: Fix /dev/oldmem interface for kdump
A change to __ioremap() broke reading /dev/oldmem because we're no
longer able to ioremap pfn 0 (d177c207, "[PATCH] powerpc: IOMMU: don't
ioremap null addresses").

We actually don't need to ioremap for anything that's part of the linear
mapping, so just read it directly.

Also make sure we're only reading one page or less at a time.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Sachin Sant <sachinp@in.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-08-20 09:50:21 +10:00
Michael Ellerman b7bcda631e powerpc: Add PPC_NOP_INSTR, a hash define for the preferred nop instruction
A bunch of code has hard-coded the value for a "nop" instruction, it
would be nice to have a #define for it.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:23 +10:00
Michael Ellerman e7a57273c6 powerpc: Allow create_branch() to return errors
Currently create_branch() creates a branch instruction for you, and
patches it into the call site.  In some circumstances it would be nice
to be able to create the instruction and patch it later, and also some
code might want to check for errors in the branch creation before
doing the patching.  A future commit will change create_branch() to
check for errors.

For callers that don't care, replace create_branch() with
patch_branch(), which just creates the branch and patches it directly.

While we're touching all the callers, change to using unsigned int *,
as this seems to match usage better.  That allows (and requires) us to
remove the volatile in the definition of vector in powermac/smp.c and
mpc86xx_smp.c, that's correct because now that we're passing vector as
an unsigned int * the compiler knows that it's value might change
across the patch_branch() call.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:19 +10:00
Michael Ellerman aaddd3eaca powerpc: Move code patching code into arch/powerpc/lib/code-patching.c
We currently have a few routines for patching code in asm/system.h, because
they didn't fit anywhere else. I'd like to clean them up a little and add
some more, so first move them into a dedicated C file - they don't need to
be inlined.

While we're moving the code, drop create_function_call(), it's intended
caller never got merged and will be replaced in future with something
different.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:18 +10:00
David S. Miller d9b2b2a277 [LIB]: Make PowerPC LMB code generic so sparc64 can use it too.
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-13 16:56:49 -08:00
Stephen Rothwell 9e4859ef54 [POWERPC] FWNMI is only used on pSeries
This saves 4k on non pSeries builds (except for iSeries where it saves
almost 4k).

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-09-19 15:25:34 +10:00
Stephen Rothwell d56c3aaa9f [POWERPC] Fix section mismatch in crash_dump.c
WARNING: vmlinux.o(.text+0x23258): Section mismatch: reference to .init.text:.lmb_reserve (between '.reserve_kdump_trampoline' and '.restore_processor_state')

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-08-17 11:02:06 +10:00
Michael Ellerman 40681b95a4 [POWERPC] Make doc comments extractable
We don't have much in the way of doc comments, but some of those we do have
don't work because they start with "/***" or "/*", not "/**" which is what
kernel-doc requires.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-08-08 17:07:04 +10:00
Michael Ellerman 473104134b [PATCH] powerpc: Kdump header cleanup
We need to know the base address of the kdump kernel even when we're not a
kdump kernel, so add a #define for it. Move the logic that sets the kdump
kernelbase into kdump.h instead of page.h.

Rename kdump_setup() to setup_kdump_trampoline() to make it clearer what it's
doing, and add an empty definition for the !CRASH_DUMP case to avoid a

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-05-19 15:02:16 +10:00
OGAWA Hirofumi 9b41046cd0 [PATCH] Don't pass boot parameters to argv_init[]
The boot cmdline is parsed in parse_early_param() and
parse_args(,unknown_bootoption).

And __setup() is used in obsolete_checksetup().

	start_kernel()
		-> parse_args()
			-> unknown_bootoption()
				-> obsolete_checksetup()

If __setup()'s callback (->setup_func()) returns 1 in
obsolete_checksetup(), obsolete_checksetup() thinks a parameter was
handled.

If ->setup_func() returns 0, obsolete_checksetup() tries other
->setup_func().  If all ->setup_func() that matched a parameter returns 0,
a parameter is seted to argv_init[].

Then, when runing /sbin/init or init=app, argv_init[] is passed to the app.
If the app doesn't ignore those arguments, it will warning and exit.

This patch fixes a wrong usage of it, however fixes obvious one only.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:53 -08:00
Paul Mackerras 6bac953fa4 powerpc: Fix compile error when CONFIG_PROC_VMCORE is not defined
We were getting elfcorehdr_addr undefined in this case.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-01-11 15:30:07 +11:00
Michael Ellerman 54c32021eb [PATCH] powerpc: Add arch-dependent copy_oldmem_page
Signed-off-by: Haren Myneni <haren@us.ibm.com>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-01-09 14:52:35 +11:00
Michael Ellerman cc53291521 [PATCH] powerpc: Add arch dependent basic infrastructure for Kdump.
Implementing the machine_crash_shutdown which will be called by
crash_kexec (called in case of a panic, sysrq etc.). Disable the
interrupts, shootdown cpus using debugger IPI and collect regs
for all CPUs.

elfcorehdr= specifies the location of elf core header stored by
the crashed kernel. This command line option will be passed by
the kexec-tools to capture kernel.

savemaxmem= specifies the actual memory size that the first kernel
has and this value will be used for dumping in the capture kernel.
This command line option will be passed by the kexec-tools to
capture kernel.

Signed-off-by: Haren Myneni <haren@us.ibm.com>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-01-09 14:52:28 +11:00
Michael Ellerman 0cc4746cad [PATCH] powerpc: Reroute interrupts from 0 + offset to PHYSICAL_START + offset
Regardless of where the kernel's linked we always get interrupts at low
addresses. This patch creates a trampoline in the first 3 pages of memory,
where interrupts land, and patches those addresses to jump into the real
kernel code at PHYSICAL_START.

We also need to reserve the trampoline code and a bit more in prom.c

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-01-09 14:52:21 +11:00