From 9c09a2518eac6277c09ee006841c94abe7305e53 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Thu, 14 Mar 2019 13:06:29 -0700 Subject: [PATCH] cpus: Initialize pseudo-random seeds for all guest cpus MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When the -seed option is given, call qemu_guest_random_seed_main, putting the subsystem into deterministic mode. Pass derived seeds to each cpu created; which is a no-op unless the subsystem is in deterministic mode. Reviewed-by: Laurent Vivier Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Daniel P. Berrangé Signed-off-by: Richard Henderson --- cpus.c | 9 +++++++++ include/qom/cpu.h | 1 + qemu-options.hx | 10 ++++++++++ vl.c | 4 ++++ 4 files changed, 24 insertions(+) diff --git a/cpus.c b/cpus.c index e58e7ab0f6..ffc57119ca 100644 --- a/cpus.c +++ b/cpus.c @@ -50,6 +50,7 @@ #include "qemu/option.h" #include "qemu/bitmap.h" #include "qemu/seqlock.h" +#include "qemu/guest-random.h" #include "tcg.h" #include "hw/nmi.h" #include "sysemu/replay.h" @@ -1276,6 +1277,7 @@ static void *qemu_kvm_cpu_thread_fn(void *arg) /* signal CPU creation */ cpu->created = true; qemu_cond_signal(&qemu_cpu_cond); + qemu_guest_random_seed_thread_part2(cpu->random_seed); do { if (cpu_can_run(cpu)) { @@ -1319,6 +1321,7 @@ static void *qemu_dummy_cpu_thread_fn(void *arg) /* signal CPU creation */ cpu->created = true; qemu_cond_signal(&qemu_cpu_cond); + qemu_guest_random_seed_thread_part2(cpu->random_seed); do { qemu_mutex_unlock_iothread(); @@ -1478,6 +1481,7 @@ static void *qemu_tcg_rr_cpu_thread_fn(void *arg) cpu->created = true; cpu->can_do_io = 1; qemu_cond_signal(&qemu_cpu_cond); + qemu_guest_random_seed_thread_part2(cpu->random_seed); /* wait for initial kick-off after machine start */ while (first_cpu->stopped) { @@ -1592,6 +1596,7 @@ static void *qemu_hax_cpu_thread_fn(void *arg) hax_init_vcpu(cpu); qemu_cond_signal(&qemu_cpu_cond); + qemu_guest_random_seed_thread_part2(cpu->random_seed); do { if (cpu_can_run(cpu)) { @@ -1631,6 +1636,7 @@ static void *qemu_hvf_cpu_thread_fn(void *arg) /* signal CPU creation */ cpu->created = true; qemu_cond_signal(&qemu_cpu_cond); + qemu_guest_random_seed_thread_part2(cpu->random_seed); do { if (cpu_can_run(cpu)) { @@ -1671,6 +1677,7 @@ static void *qemu_whpx_cpu_thread_fn(void *arg) /* signal CPU creation */ cpu->created = true; qemu_cond_signal(&qemu_cpu_cond); + qemu_guest_random_seed_thread_part2(cpu->random_seed); do { if (cpu_can_run(cpu)) { @@ -1724,6 +1731,7 @@ static void *qemu_tcg_cpu_thread_fn(void *arg) cpu->can_do_io = 1; current_cpu = cpu; qemu_cond_signal(&qemu_cpu_cond); + qemu_guest_random_seed_thread_part2(cpu->random_seed); /* process any pending work */ cpu->exit_request = 1; @@ -2071,6 +2079,7 @@ void qemu_init_vcpu(CPUState *cpu) cpu->nr_cores = smp_cores; cpu->nr_threads = smp_threads; cpu->stopped = true; + cpu->random_seed = qemu_guest_random_seed_thread_part1(); if (!cpu->as) { /* If the target cpu hasn't set up any address spaces itself, diff --git a/include/qom/cpu.h b/include/qom/cpu.h index 32983f27c3..98e12d914c 100644 --- a/include/qom/cpu.h +++ b/include/qom/cpu.h @@ -375,6 +375,7 @@ struct CPUState { int singlestep_enabled; int64_t icount_budget; int64_t icount_extra; + uint64_t random_seed; sigjmp_buf jmp_env; QemuMutex work_mutex; diff --git a/qemu-options.hx b/qemu-options.hx index 5daa5a8fb0..7ae3373a00 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -3641,6 +3641,16 @@ the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized block starting at 0xffffffc00005f000. ETEXI +DEF("seed", HAS_ARG, QEMU_OPTION_seed, \ + "-seed number seed the pseudo-random number generator\n", + QEMU_ARCH_ALL) +STEXI +@item -seed @var{number} +@findex -seed +Force the guest to use a deterministic pseudo-random number generator, seeded +with @var{number}. This does not affect crypto routines within the host. +ETEXI + DEF("L", HAS_ARG, QEMU_OPTION_L, \ "-L path set the directory for the BIOS, VGA BIOS and keymaps\n", QEMU_ARCH_ALL) diff --git a/vl.c b/vl.c index 201144b162..5550bd7693 100644 --- a/vl.c +++ b/vl.c @@ -128,6 +128,7 @@ int main(int argc, char **argv) #include "qapi/qapi-commands-ui.h" #include "qapi/qmp/qerror.h" #include "sysemu/iothread.h" +#include "qemu/guest-random.h" #define MAX_VIRTIO_CONSOLES 1 @@ -3349,6 +3350,9 @@ int main(int argc, char **argv, char **envp) case QEMU_OPTION_DFILTER: qemu_set_dfilter_ranges(optarg, &error_fatal); break; + case QEMU_OPTION_seed: + qemu_guest_random_seed_main(optarg, &error_fatal); + break; case QEMU_OPTION_s: add_device_config(DEV_GDB, "tcp::" DEFAULT_GDBSTUB_PORT); break;