Re: [Qemu-devel] [RFC PATCH] QEMU may write to system_memory before guest starts

[Peter Maydell]

On Tue, 19 Mar 2019 at 12:42, Igor Mammedov <address@hidden> wrote:
> on aarch(64) we also load dtb into main RAM currently only on boot,

Hmm? We load the DTB in hw/arm/boot.c using rom_add_blob_fixed_as(),
which means that it will use this "rom blob loading" mechanism,
so it should be re-copied into RAM on reset.

> and I was planning to move it to reset stage to accommodate
> hotplug usecase so that guest would pick up hotplugged
> devices after reboot.

The problem here is that this is trying to change the
contents of the DTB blob on a reboot, which is not
supported by the ROM blob mechanism, which assumes that
these things are immutable.

thanks
-- PMM