Rather than rebooting into a system with no entropy, regenerate the RNG seed before rebooting, so that the new system has a fresh seed. Fixes: a1ee38ab1a75 ("m68k: virt: Use RNG seed from bootinfo block") Signed-off-by: Jason A. Donenfeld <Jason@xxxxxxxxx> --- arch/m68k/virt/config.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/arch/m68k/virt/config.c b/arch/m68k/virt/config.c index 4ab22946ff68..d4627840e35b 100644 --- a/arch/m68k/virt/config.c +++ b/arch/m68k/virt/config.c @@ -45,10 +45,18 @@ static void virt_halt(void) ; } +static const struct bi_record *rng_seed_record; + static void virt_reset(void) { void __iomem *base = (void __iomem *)virt_bi_data.ctrl.mmio; + if (rng_seed_record && rng_seed_record->size > sizeof(*rng_seed_record) + 2) { + u16 len = rng_seed_record->size - sizeof(*rng_seed_record) - 2; + get_random_bytes((u8 *)rng_seed_record->data + 2, len); + *(u16 *)rng_seed_record->data = cpu_to_be16(len); + } + iowrite32be(CMD_RESET, base + VIRT_CTRL_REG_CMD); local_irq_disable(); while (1) @@ -101,6 +109,8 @@ int __init virt_parse_bootinfo(const struct bi_record *record) * length to prevent kexec from using it. */ memzero_explicit((void *)data, len + 2); + /* Store a reference to be filled in on reboot. */ + rng_seed_record = record; break; } default: -- 2.37.3