hw/ppc: pass random seed to fdt

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-rc6. The rng-seed node is part of the DT spec. Set
this on the paravirt platforms, spapr and e500, just as is done on other
architectures with paravirt hardware.

Cc: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20220712135114.289855-1-Jason@zx2c4.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
This commit is contained in:
Jason A. Donenfeld 2022-07-12 15:51:14 +02:00 committed by Daniel Henrique Barboza
parent 285c471f82
commit c4b075318e
2 changed files with 10 additions and 0 deletions

View File

@ -17,6 +17,7 @@
#include "qemu/osdep.h"
#include "qemu/datadir.h"
#include "qemu/units.h"
#include "qemu/guest-random.h"
#include "qapi/error.h"
#include "e500.h"
#include "e500-ccsr.h"
@ -346,6 +347,7 @@ static int ppce500_load_device_tree(PPCE500MachineState *pms,
};
const char *dtb_file = machine->dtb;
const char *toplevel_compat = machine->dt_compatible;
uint8_t rng_seed[32];
if (dtb_file) {
char *filename;
@ -403,6 +405,9 @@ static int ppce500_load_device_tree(PPCE500MachineState *pms,
if (ret < 0)
fprintf(stderr, "couldn't set /chosen/bootargs\n");
qemu_guest_getrandom_nofail(rng_seed, sizeof(rng_seed));
qemu_fdt_setprop(fdt, "/chosen", "rng-seed", rng_seed, sizeof(rng_seed));
if (kvm_enabled()) {
/* Read out host's frequencies */
clock_freq = kvmppc_get_clockfreq();

View File

@ -27,6 +27,7 @@
#include "qemu/osdep.h"
#include "qemu/datadir.h"
#include "qemu/memalign.h"
#include "qemu/guest-random.h"
#include "qapi/error.h"
#include "qapi/qapi-events-machine.h"
#include "qapi/qapi-events-qdev.h"
@ -1014,6 +1015,7 @@ static void spapr_dt_chosen(SpaprMachineState *spapr, void *fdt, bool reset)
{
MachineState *machine = MACHINE(spapr);
SpaprMachineClass *smc = SPAPR_MACHINE_GET_CLASS(machine);
uint8_t rng_seed[32];
int chosen;
_FDT(chosen = fdt_add_subnode(fdt, 0, "chosen"));
@ -1091,6 +1093,9 @@ static void spapr_dt_chosen(SpaprMachineState *spapr, void *fdt, bool reset)
spapr_dt_ov5_platform_support(spapr, fdt, chosen);
}
qemu_guest_getrandom_nofail(rng_seed, sizeof(rng_seed));
_FDT(fdt_setprop(fdt, chosen, "rng-seed", rng_seed, sizeof(rng_seed)));
_FDT(spapr_dt_ovec(fdt, chosen, spapr->ov5_cas, "ibm,architecture-vec-5"));
}