Re: [PATCH] hw/riscv: virt: pass random seed to fdt

[Alistair Francis]

On Wed, Jun 15, 2022 at 2:07 PM Bin Meng <bmeng.cn@gmail.com> wrote:
>
> On Mon, Jun 13, 2022 at 8:08 PM Jason A. Donenfeld <Jason@zx2c4.com> wrote:
> >
> > If the FDT contains /chosen/rng-seed, then the Linux RNG will use it to
> > initialize early. Set this using the usual guest random number
> > generation function. This is confirmed to successfully initialize the
> > RNG on Linux 5.19-rc2.
> >
> > Cc: Alistair Francis <alistair.francis@wdc.com>
> > Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

Thanks!

Applied to riscv-to-apply.next with the full stop removed

Alistair

> > ---
> >  hw/riscv/virt.c | 6 ++++++
> >  1 file changed, 6 insertions(+)
> >
> > diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
> > index bc424dd2f5..368a723bf6 100644
> > --- a/hw/riscv/virt.c
> > +++ b/hw/riscv/virt.c
> > @@ -21,6 +21,7 @@
> >  #include "qemu/osdep.h"
> >  #include "qemu/units.h"
> >  #include "qemu/error-report.h"
> > +#include "qemu/guest-random.h"
> >  #include "qapi/error.h"
> >  #include "hw/boards.h"
> >  #include "hw/loader.h"
> > @@ -998,6 +999,7 @@ static void create_fdt(RISCVVirtState *s, const 
> > MemMapEntry *memmap,
> >      MachineState *mc = MACHINE(s);
> >      uint32_t phandle = 1, irq_mmio_phandle = 1, msi_pcie_phandle = 1;
> >      uint32_t irq_pcie_phandle = 1, irq_virtio_phandle = 1;
> > +    uint8_t rng_seed[32];
> >
> >      if (mc->dtb) {
> >          mc->fdt = load_device_tree(mc->dtb, &s->fdt_size);
> > @@ -1046,6 +1048,10 @@ update_bootargs:
> >      if (cmdline && *cmdline) {
> >          qemu_fdt_setprop_string(mc->fdt, "/chosen", "bootargs", cmdline);
> >      }
> > +
> > +    /* Pass seed to RNG. */
>
> nits: please remove the ending period
>
> > +    qemu_guest_getrandom_nofail(rng_seed, sizeof(rng_seed));
> > +    qemu_fdt_setprop(mc->fdt, "/chosen", "rng-seed", rng_seed, 
> > sizeof(rng_seed));
> >  }
> >
> >  static inline DeviceState *gpex_pcie_init(MemoryRegion *sys_mem,
> > --
>
> Otherwise,
> Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
>