diff mbox series

hw/mips: boston: pass random seed to fdt

Message ID 20220719120843.134392-1-Jason@zx2c4.com
State New
Headers show
Series hw/mips: boston: pass random seed to fdt | expand

Commit Message

Jason A. Donenfeld July 19, 2022, 12:08 p.m. UTC 
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>
---
 hw/mips/boston.c | 5 +++++
 1 file changed, 5 insertions(+)
diff mbox series

Patch

diff --git a/hw/mips/boston.c b/hw/mips/boston.c
index 1debca18ec..d2ab9da1a0 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 @@  static const void *boston_fdt_filter(void *opaque, const void *fdt_orig,
     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 @@  static const void *boston_fdt_filter(void *opaque, const void *fdt_orig,
         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);