sandbox: Try to start the RAM buffer at a particular address

Use a starting address of 256MB which should be available. This helps to
make sandbox RAM buffers pointers more recognisable.

Signed-off-by: Simon Glass <sjg@chromium.org>

diff --git a/arch/sandbox/cpu/os.c b/arch/sandbox/cpu/os.c
index 07e4647..325ded5 100644 (file)
--- a/arch/sandbox/cpu/os.c
+++ b/arch/sandbox/cpu/os.c
@@ -174,7 +174,12 @@ void *os_malloc(size_t length)
        struct os_mem_hdr *hdr;
        int page_size = getpagesize();
 
-       hdr = mmap(NULL, length + page_size,
+       /*
+        * Use an address that is hopefully available to us so that pointers
+        * to this memory are fairly obvious. If we end up with a different
+        * address, that's fine too.
+        */
+       hdr = mmap((void *)0x10000000, length + page_size,
                   PROT_READ | PROT_WRITE | PROT_EXEC,
                   MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
        if (hdr == MAP_FAILED)