Hello, The generic-fuzzer often provides virtual-devices with bogus DMA addresses (e.g. 0x4141414141414141). The probability that these fuzzed addresses actually land within RAM is quite small. The fuzzer eventually finds valid addresses, however, this takes some time, and this problem is compounded when the device accesses multiple DMA regions. This series adds a "sparse" memory device, and configures it for the generic-fuzzer. This allows us to simulate 16 EB ram (only a tiny portion actually populated). Thus, almost any randomly generated 64-bit address will land in memory that the fuzzer can populate with data.
Patch 1 adds the sparse-mem device Patch 2 adds tests for the device Patch 3 configures the generic-fuzzer to use the sparse-mem device -Alex Alexander Bulekov (3): memory: add a sparse memory device memory: add tests for the sparse-mem device fuzz: configure a sparse-mem device, by default MAINTAINERS | 2 + hw/mem/meson.build | 1 + hw/mem/sparse-mem.c | 154 ++++++++++++++++++++++++++++++++ tests/qtest/fuzz/generic_fuzz.c | 2 +- tests/qtest/meson.build | 3 +- tests/qtest/sparse-mem-test.c | 88 ++++++++++++++++++ 6 files changed, 248 insertions(+), 2 deletions(-) create mode 100644 hw/mem/sparse-mem.c create mode 100644 tests/qtest/sparse-mem-test.c -- 2.28.0