For testing, it can be useful to simulate an enormous amount of memory
(e.g. 2^64 RAM). This adds an MMIO device that acts as sparse memory.
When something writes a nonzero value to a sparse-mem address, we
allocate a block of memory. For now, since the only user of this device
is the fuzzer, we do not track and free zeroed blocks. The device has a
very low priority (so it can be mapped beneath actual RAM, and virtual
device MMIO regions).
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This just implements the bare minimum to cause the boot block to skip
memory initialization.
Reviewed-by: Tyrone Ting <kfting@nuvoton.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Alexander Bulekov <alxndr@bu.edu>
Signed-off-by: Havard Skinnemoen <hskinnemoen@google.com>
Message-id: 20200911052101.2602693-10-hskinnemoen@google.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>