Re: [PATCH v4 13/25] powernv/fadump: support copying multiple kernel memory regions

On 2019-07-16 17:03:30 Tue, Hari Bathini wrote:

Firmware uses 32-bit field for region size while copying/backing-up
memory during MPIPL. So, the maximum copy size for a region would
be a page less than 4GB (aligned to pagesize) but FADump capture
kernel usually needs more memory than that to be preserved to avoid
running into out of memory errors.

So, request firmware to copy multiple kernel memory regions instead
of just one (which worked fine for pseries as 64-bit field was used
for size there). With support to copy multiple kernel memory regions,
also handle holes in the memory area to be preserved. Support as many
as 128 kernel memory regions. This allows having an adequate FADump
capture kernel size for different scenarios.

Can you split this patch into 2 ? One for handling holes in boot memory
and other for handling 4Gb region size ? So that it will be easy to
review changes.

Thanks,
-Mahesh.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
---
 arch/powerpc/kernel/fadump-common.c          |   15 ++
 arch/powerpc/kernel/fadump-common.h          |   16 ++
 arch/powerpc/kernel/fadump.c                 |  173 ++++++++++++++++++++++----
 arch/powerpc/platforms/powernv/opal-fadump.c |   25 +++-
 arch/powerpc/platforms/powernv/opal-fadump.h |    5 -
 arch/powerpc/platforms/pseries/rtas-fadump.c |   12 ++
 arch/powerpc/platforms/pseries/rtas-fadump.h |    5 +
 7 files changed, 211 insertions(+), 40 deletions(-)