[Qemu-devel] [PATCH v2 0/5] Let boards state maximum RAM limits in QEMUMachine struct

[Peter Maydell]

This fairly simple patchset adds a new 'max_ram' field to the QEMUMachine
structure so that a board model can specify the maximum RAM it will accept.
We can then produce a friendly diagnostic message when the user tries to
start qemu with a '-m' option asking for more RAM than that. (Currently
most of the ARM devboard models respond with an obscure guest crash when
the guest tries to access RAM and finds device registers instead.)

If no maximum size is specified we default to the old behaviour of
"do not impose any limit".

The advantage of doing this in vl.c rather than in each board (apart
from avoiding code duplication) is that we can distinguish between
"the user asked for more RAM than we support" (an error) and "the global
default RAM size is more than our maximum" (just cap the RAM size to
the board maximum).

Changes in v2:
 * use target_physaddr_t rather than ram_addr_t for max_ram, so
   we can specify maximum ram sizes for 64 bit target boards
 * new patches 3,4 which update sun4m to use the generic max_ram, so
   we can delete the sun4m-specific code which was doing the same job
 * patch 5 does some tidy-up of sun4m init functions; not strictly
   related but the assert() at least is enabled by the cleanup done
   in patch 3.

The number of changed lines in sun4m.c is a bit alarming but it's
almost all just moving code around...

Peter Maydell (5):
  Allow boards to specify maximum RAM size
  hw: Add maximum RAM specifications for ARM devboard models
  hw/sun4m: Move QEMUMachine structs into sun4*_hwdef structs
  hw/sun4m: Use the QEMUMachine max_ram to implement memory limit
  hw/sun4m: Use a macro to hide the repetitive board init functions

 hw/boards.h       |    1 +
 hw/integratorcp.c |    1 +
 hw/realview.c     |   11 +
 hw/sun4m.c        |  586 ++++++++++++++++++++++-------------------------------
 hw/versatilepb.c  |    5 +
 vl.c              |   16 ++-
 6 files changed, 273 insertions(+), 347 deletions(-)