On Mon, 19 Jul 2021 at 10:35, Hiroko Shimizu <hiroko07...@gmail.com> wrote: > > Hello, > I'd like to initialize RAM from a specific file when RAM is created. > Then, I tried using memory_region_init_ram_from_file().
If you want to put something specific into RAM on startup the easiest way is to use the 'generic loader' on the command line: https://qemu-project.gitlab.io/qemu/system/generic-loader.html You only need to use memory_region_init_ram_from_file() if you want guest changes to the RAM as it runs to be written back to the file. > I wonder what file format is necessary. The file is mmap()ed, so it is raw binary. If you really need the "write back guest memory changes" behaviour, I would suggest that rather than making your machine create the RAM memory region in a specific file-backed way, you instead create the RAM memory region normally, and on the commandline use -object memory-backend-file,id=myram,[other-options] -machine memory-backend=myram to make QEMU use that file backend for the machine's main RAM. (Check the docs for what the 'other-options' ought to be.) thanks -- PMM
