commit 5e19cc68fb42c6ecabe5cf37012c887d25ffd144
author Jason A. Donenfeld <Jason@zx2c4.com> Tue Jul 19 14:08:43 2022 +0200
committer Paolo Bonzini <pbonzini@redhat.com> Fri Jul 22 19:01:44 2022 +0200
tree c1710eb78648d60ae1a65595af5fc863a4b736d0
parent 6b23a6791685ac1bf071c0ebb35004e427c1806d

hw/mips: boston: 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 FDT node is part of the DT specification.

I'd do the same for other MIPS platforms but boston is the only one that
seems to use FDT.

Cc: Paul Burton <paulburton@kernel.org>
Cc: Aleksandar Rikalo <aleksandar.rikalo@syrmia.com>
Cc: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Message-Id: <20220719120843.134392-1-Jason@zx2c4.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

hw/mips/boston.c

diff --git a/hw/mips/boston.c b/hw/mips/boston.c
index 1debca1..d2ab9da 100644
--- a/hw/mips/boston.c
+++ b/hw/mips/boston.c
@@ -34,6 +34,7 @@
 #include "hw/qdev-properties.h"
 #include "qapi/error.h"
 #include "qemu/error-report.h"
+#include "qemu/guest-random.h"
 #include "qemu/log.h"
 #include "chardev/char.h"
 #include "sysemu/device_tree.h"
@@ -363,6 +364,7 @@
     size_t ram_low_sz, ram_high_sz;
     size_t fdt_sz = fdt_totalsize(fdt_orig) * 2;
     g_autofree void *fdt = g_malloc0(fdt_sz);
+    uint8_t rng_seed[32];
 
     err = fdt_open_into(fdt_orig, fdt, fdt_sz);
     if (err) {
@@ -370,6 +372,9 @@
         return NULL;
     }
 
+    qemu_guest_getrandom_nofail(rng_seed, sizeof(rng_seed));
+    qemu_fdt_setprop(fdt, "/chosen", "rng-seed", rng_seed, sizeof(rng_seed));
+
     cmdline = (machine->kernel_cmdline && machine->kernel_cmdline[0])
             ? machine->kernel_cmdline : " ";
     err = qemu_fdt_setprop_string(fdt, "/chosen", "bootargs", cmdline);