s390/hibernate: Save and restore absolute zero pages
authorMichael Holzheu <holzheu@linux.vnet.ibm.com>
Mon, 8 Apr 2013 14:09:31 +0000 (16:09 +0200)
committerMartin Schwidefsky <schwidefsky@de.ibm.com>
Wed, 17 Apr 2013 12:07:30 +0000 (14:07 +0200)
commit91c15a951091a64a5f048ff93292057e3b590b6f
tree33e7f36ede3deaa958d14736d83b401b0bc03123
parent5294ee00a16567355c85b849742e5219aad880d0
s390/hibernate: Save and restore absolute zero pages

Since commit 5f954c34 ([S390] hibernation: fix lowcore handling)
the absolute zero lowcore is lost during suspend/resume.
For example, this leads to the problem that the re-IPL device
for kdump is no longer set after resume.

With this patch during suspend a buffer is allocated in the new PM
notifier "suspend_pm_cb" and then the absolute zero lowcore is saved
to that buffer. The resume code then copies back this buffer to
absolute zero and afterwards the PM notifier releases the memory.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
arch/s390/kernel/entry.h
arch/s390/kernel/suspend.c
arch/s390/kernel/swsusp_asm64.S