This series brings qmp-dump-guest-memory to arm and aarch64
targets. I've detailed my testing and the results in the
following table.
arm/aarch64 kvm guest kdump testing (P - PASS, F - FAIL). Testing done
with a latest mainline crash utility patched with [*]
.-----------------------------------------------------------------------.
| Host | arm32 | arm64 | arm64 | arm64 |
|---------------------------------------|-------|-------|-------|-------|
| Guest | arm32 | arm64 | arm64 | arm32 |
|---------------------------------------|-------|-------|-------|-------|
| Pagesize| 4K | 4K | 64K | 4K |
|=======================================================================|
| kdump in guest | F[1] | P[2] | P[3] | F[1] |
|---------------------------------------|-------|-------|-------|-------|
| qmp-dump-guest-memory <filename>[4] | P | P | P | P |
|---------------------------------------|-------|-------|-------|-------|
| qmp-dump-guest-memory -z <filename>[5]| F[8] | P | P | F[8] |
|---------------------------------------|-------|-------|-------|-------|
| qmp-dump-guest-memory -l <filename>[6]| F[8] | P | P | F[8] |
|---------------------------------------|-------|-------|-------|-------|
| qmp-dump-guest-memory -s <filename>[7]| F[8] | P | P | F[8] |
.-----------------------------------------------------------------------.
[1] Kernel v4.4-rc1 crashes with a NULL pointer dereference at virtual
address 00000000 in a memcpy (crash_kexec/machine_kexec/fncpy/memcpy).
Needs kernel debugging.
[2] Not sure about mainline, but works with the RHEL kernel,
makedumpfile does not yet support arm64 with 4K pages, but using
'core_collector cp' in /etc/kdump.conf allows saving an uncompressed
elf file.
[3] Not sure about mainline, but works with the RHEL kernel,
uses makedumpfile, thus generates a makedumpfile formatted file
using zlib compression.
[4] No format specified, creates an uncompressed elf formatted file.
[5] makedumpfile format, with zlib compression
[6] makedumpfile format, with lzo compression
[7] makedumpfile format, with snappy compression
[8] The crash utility doesn't seem to like arm32 dumps in makedumpfile
format. Looks like the physical page bitmap is all zeros? Needs
qemu and crash debugging.
Additional notes:
1) QEMU also has scripts/dump-guest-memory.py, which can and should be
updated to support multiple architectures, pagesizes, and physbases.
This is currently left as future work.
[*] https://www.redhat.com/archives/crash-utility/2015-November/msg00031.html
Andrew Jones (5):
qapi-schema: dump-guest-memory: Improve text
dump: qemunotes aren't commonly needed
dump: allow target to set the page size
dump: allow target to set the phys_base
target-arm: support QMP dump-guest-memory
dump.c | 129 +++++++++++++++----------
include/sysemu/dump-arch.h | 9 +-
include/sysemu/dump.h | 11 +--
qapi-schema.json | 4 +-
qom/cpu.c | 4 +-
target-arm/Makefile.objs | 3 +-
target-arm/arch_dump.c | 222 ++++++++++++++++++++++++++++++++++++++++++++
target-arm/cpu-qom.h | 5 +
target-arm/cpu.c | 3 +
target-ppc/arch_dump.c | 6 --
target-ppc/cpu-qom.h | 2 -
target-ppc/translate_init.c | 1 -
target-s390x/arch_dump.c | 6 --
target-s390x/cpu-qom.h | 2 -
target-s390x/cpu.c | 1 -
15 files changed, 321 insertions(+), 87 deletions(-)
create mode 100644 target-arm/arch_dump.c
--
2.4.3
