* [PATCH] Relocatable kdump kernel support in kexec-tools
@ 2008-09-30 12:56 Mohan Kumar M
2008-10-08 6:11 ` Simon Horman
0 siblings, 1 reply; 2+ messages in thread
From: Mohan Kumar M @ 2008-09-30 12:56 UTC (permalink / raw)
To: kexec; +Cc: ppcdev, paulus
Relocatable kdump kernel support in kexec-tools
This patch adds relocatable kernel support for kdump in the kexec-tools
code. A signature (0xfeed1234) is passed in r6 from panic code to the
purgatory code through kexec_sequence function. The signature is used to
differentiate between relocatable kdump kernel and non-kdump kernels.
The purgatory code compares the signature and sets the __kdump_flag in
head_64.S by using the offset with respect to next kernel load address.
During the boot up, kernel code checks __kdump_flag and if it is set, the
kernel will behave as relocatable kdump kernel.
Signed-off-by: Mohan Kumar M <mohan@in.ibm.com>
---
diff --git a/purgatory/arch/ppc64/v2wrap.S b/purgatory/arch/ppc64/v2wrap.S
index b3563de..f69dad2 100644
--- a/purgatory/arch/ppc64/v2wrap.S
+++ b/purgatory/arch/ppc64/v2wrap.S
@@ -45,6 +45,7 @@
oris rn,rn,name##@h; \
ori rn,rn,name##@l
+#define KDUMP_SIGNATURE 0xfeed1234
.machine ppc64
.globl purgatory_start
@@ -64,6 +65,7 @@ master:
isync
mr 17,3 # save cpu id to r17
mr 15,4 # save physical address in reg15
+ mr 18,6 # save kdump flag in reg18
LOADADDR(6,my_toc)
ld 2,0(6) #setup toc
@@ -94,6 +96,12 @@ master:
mtctr 4 # prepare branch too
mr 3,16 # restore dt address
+ LOADADDR(6,KDUMP_SIGNATURE)
+ cmpd 18,6
+ bne regular
+ li 7,1
+ std 7,24(4) # mark kdump flag at kernel
+regular:
lwz 7,0(4) # get the first instruction that we stole
stw 7,0(0) # and put it in the slave loop at 0
# skip cache flush, do we care?
^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [PATCH] Relocatable kdump kernel support in kexec-tools
2008-09-30 12:56 [PATCH] Relocatable kdump kernel support in kexec-tools Mohan Kumar M
@ 2008-10-08 6:11 ` Simon Horman
0 siblings, 0 replies; 2+ messages in thread
From: Simon Horman @ 2008-10-08 6:11 UTC (permalink / raw)
To: Mohan Kumar M; +Cc: ppcdev, kexec, paulus
On Tue, Sep 30, 2008 at 06:26:21PM +0530, Mohan Kumar M wrote:
> Relocatable kdump kernel support in kexec-tools
>
> This patch adds relocatable kernel support for kdump in the kexec-tools
> code. A signature (0xfeed1234) is passed in r6 from panic code to the
> purgatory code through kexec_sequence function. The signature is used to
> differentiate between relocatable kdump kernel and non-kdump kernels.
>
> The purgatory code compares the signature and sets the __kdump_flag in
> head_64.S by using the offset with respect to next kernel load address.
> During the boot up, kernel code checks __kdump_flag and if it is set, the
> kernel will behave as relocatable kdump kernel.
Thanks Mohan, applied.
--
Simon Horman
VA Linux Systems Japan K.K., Sydney, Australia Satellite Office
H: www.vergenet.net/~horms/ W: www.valinux.co.jp/en
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2008-10-08 6:11 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2008-09-30 12:56 [PATCH] Relocatable kdump kernel support in kexec-tools Mohan Kumar M
2008-10-08 6:11 ` Simon Horman
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).