fuzz: Declare DMA Read callback function
This patch declares the fuzz_dma_read_cb function and uses the
preprocessor and linker(weak symbols) to handle these cases:
When we build softmmu/all with --enable-fuzzing, there should be no
strong symbol defined for fuzz_dma_read_cb, and we link against a weak
stub function.
When we build softmmu/fuzz with --enable-fuzzing, we link against the
strong symbol in generic_fuzz.c
When we build softmmu/all without --enable-fuzzing, fuzz_dma_read_cb is
an empty, inlined function. As long as we don't call any other functions
when building the arguments, there should be no overhead.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-Id: <20201023150746.107063-6-alxndr@bu.edu>
Signed-off-by: Thomas Huth <thuth@redhat.com>
diff --git a/include/exec/memory.h b/include/exec/memory.h
index 93d27bf..4aaf578 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -47,6 +47,14 @@
size_t len,
MemoryRegion *mr,
bool is_write);
+#else
+static inline void fuzz_dma_read_cb(size_t addr,
+ size_t len,
+ MemoryRegion *mr,
+ bool is_write)
+{
+ /* Do Nothing */
+}
#endif
extern bool global_dirty_log;
diff --git a/softmmu/memory.c b/softmmu/memory.c
index a5d1641..cec0e0f 100644
--- a/softmmu/memory.c
+++ b/softmmu/memory.c
@@ -3246,6 +3246,19 @@
vmstate_register_ram(mr, owner_dev);
}
+/*
+ * Support softmmu builds with CONFIG_FUZZ using a weak symbol and a stub for
+ * the fuzz_dma_read_cb callback
+ */
+#ifdef CONFIG_FUZZ
+void __attribute__((weak)) fuzz_dma_read_cb(size_t addr,
+ size_t len,
+ MemoryRegion *mr,
+ bool is_write)
+{
+}
+#endif
+
static const TypeInfo memory_region_info = {
.parent = TYPE_OBJECT,
.name = TYPE_MEMORY_REGION,
