[PATCH RFC 7/7] Revert "hw/i386: pass RNG seed via setup_data entry"

Michael S. Tsirkin
2023-02-08T21:14:12Z

This reverts commit 67f7e426e53833a5db75b0d813e8d537b8a75bd2.

Fixes: 67f7e426e5 ("hw/i386: pass RNG seed via setup_data entry")
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
include/hw/i386/pc.h | 3 ---
include/hw/i386/x86.h | 3 +--
hw/i386/microvm.c | 2 +-
hw/i386/pc.c | 4 ++--
hw/i386/pc_piix.c | 2 --
hw/i386/pc_q35.c | 2 --
hw/i386/x86.c | 26 ++++----------------------
7 files changed, 8 insertions(+), 34 deletions(-)

diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index 66e3d059ef..44b08554fa 100644
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -127,9 +127,6 @@ struct PCMachineClass {

/* create kvmclock device even when KVM PV features are not exposed */
bool kvmclock_create_always;
-
- /* skip passing an rng seed for legacy machines */
- bool legacy_no_rng_seed;
};

#define TYPE_PC_MACHINE "generic-pc-machine"
diff --git a/include/hw/i386/x86.h b/include/hw/i386/x86.h
index 62fa5774f8..df82c5fd42 100644
--- a/include/hw/i386/x86.h
+++ b/include/hw/i386/x86.h
@@ -126,8 +126,7 @@ void x86_bios_rom_init(MachineState *ms, const char *default_firmware,
void x86_load_linux(X86MachineState *x86ms,
FWCfgState *fw_cfg,
int acpi_data_size,
- bool pvh_enabled,
- bool legacy_no_rng_seed);
+ bool pvh_enabled);

bool x86_machine_is_smm_enabled(const X86MachineState *x86ms);
bool x86_machine_is_acpi_enabled(const X86MachineState *x86ms);
diff --git a/hw/i386/microvm.c b/hw/i386/microvm.c
index 170a331e3f..b231ceda9a 100644
--- a/hw/i386/microvm.c
+++ b/hw/i386/microvm.c
@@ -330,7 +330,7 @@ static void microvm_memory_init(MicrovmMachineState *mms)
rom_set_fw(fw_cfg);

if (machine->kernel_filename != NULL) {
- x86_load_linux(x86ms, fw_cfg, 0, true, false);
+ x86_load_linux(x86ms, fw_cfg, 0, true);
}

if (mms->option_roms) {
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 6e592bd969..2c5f675ba4 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -804,7 +804,7 @@ void xen_load_linux(PCMachineState *pcms)
rom_set_fw(fw_cfg);

x86_load_linux(x86ms, fw_cfg, pcmc->acpi_data_size,
- pcmc->pvh_enabled, pcmc->legacy_no_rng_seed);
+ pcmc->pvh_enabled);
for (i = 0; i < nb_option_roms; i++) {
assert(!strcmp(option_rom[i].name, "linuxboot.bin") ||
!strcmp(option_rom[i].name, "linuxboot_dma.bin") ||
@@ -1124,7 +1124,7 @@ void pc_memory_init(PCMachineState *pcms,

if (linux_boot) {
x86_load_linux(x86ms, fw_cfg, pcmc->acpi_data_size,
- pcmc->pvh_enabled, pcmc->legacy_no_rng_seed);
+ pcmc->pvh_enabled);
}

for (i = 0; i < nb_option_roms; i++) {
diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
index df64dd8dcc..839bd65df5 100644
--- a/hw/i386/pc_piix.c
+++ b/hw/i386/pc_piix.c
@@ -476,9 +476,7 @@ DEFINE_I440FX_MACHINE(v7_2, "pc-i440fx-7.2", NULL,

static void pc_i440fx_7_1_machine_options(MachineClass *m)
{
- PCMachineClass *pcmc = PC_MACHINE_CLASS(m);
pc_i440fx_7_2_machine_options(m);
- pcmc->legacy_no_rng_seed = true;
compat_props_add(m->compat_props, hw_compat_7_1, hw_compat_7_1_len);
compat_props_add(m->compat_props, pc_compat_7_1, pc_compat_7_1_len);
}
diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c
index 66cd718b70..e6e3966262 100644
--- a/hw/i386/pc_q35.c
+++ b/hw/i386/pc_q35.c
@@ -395,9 +395,7 @@ DEFINE_Q35_MACHINE(v7_2, "pc-q35-7.2", NULL,

static void pc_q35_7_1_machine_options(MachineClass *m)
{
- PCMachineClass *pcmc = PC_MACHINE_CLASS(m);
pc_q35_7_2_machine_options(m);
- pcmc->legacy_no_rng_seed = true;
compat_props_add(m->compat_props, hw_compat_7_1, hw_compat_7_1_len);
compat_props_add(m->compat_props, pc_compat_7_1, pc_compat_7_1_len);
}
diff --git a/hw/i386/x86.c b/hw/i386/x86.c
index 4831193c86..80be3032cc 100644
--- a/hw/i386/x86.c
+++ b/hw/i386/x86.c
@@ -26,7 +26,6 @@
#include "qemu/cutils.h"
#include "qemu/units.h"
#include "qemu/datadir.h"
-#include "qemu/guest-random.h"
#include "qapi/error.h"
#include "qapi/qmp/qerror.h"
#include "qapi/qapi-visit-common.h"
@@ -771,8 +770,7 @@ static bool load_elfboot(const char *kernel_filename,
void x86_load_linux(X86MachineState *x86ms,
FWCfgState *fw_cfg,
int acpi_data_size,
- bool pvh_enabled,
- bool legacy_no_rng_seed)
+ bool pvh_enabled)
{
bool linuxboot_dma_enabled = X86_MACHINE_GET_CLASS(x86ms)->fwcfg_dma_enabled;
uint16_t protocol;
@@ -780,7 +778,7 @@ void x86_load_linux(X86MachineState *x86ms,
int dtb_size, setup_data_offset;
uint32_t initrd_max;
uint8_t header[8192], *setup, *kernel;
- hwaddr real_addr, prot_addr, cmdline_addr, initrd_addr = 0, first_setup_data = 0;
+ hwaddr real_addr, prot_addr, cmdline_addr, initrd_addr = 0;
FILE *f;
char *vmode;
MachineState *machine = MACHINE(x86ms);
@@ -790,7 +788,6 @@ void x86_load_linux(X86MachineState *x86ms,
const char *dtb_filename = machine->dtb;
const char *kernel_cmdline = machine->kernel_cmdline;
SevKernelLoaderContext sev_load_ctx = {};
- enum { RNG_SEED_LENGTH = 32 };

/* Align to 16 bytes as a paranoia measure */
cmdline_size = (strlen(kernel_cmdline) + 16) & ~15;
@@ -1070,31 +1067,16 @@ void x86_load_linux(X86MachineState *x86ms,
kernel_size = setup_data_offset + sizeof(struct setup_data) + dtb_size;
kernel = g_realloc(kernel, kernel_size);

+ stq_p(header + 0x250, prot_addr + setup_data_offset);

setup_data = (struct setup_data *)(kernel + setup_data_offset);
- setup_data->next = cpu_to_le64(first_setup_data);
- first_setup_data = prot_addr + setup_data_offset;
+ setup_data->next = 0;
setup_data->type = cpu_to_le32(SETUP_DTB);
setup_data->len = cpu_to_le32(dtb_size);

load_image_size(dtb_filename, setup_data->data, dtb_size);
}

- if (!legacy_no_rng_seed) {
- setup_data_offset = QEMU_ALIGN_UP(kernel_size, 16);
- kernel_size = setup_data_offset + sizeof(struct setup_data) + RNG_SEED_LENGTH;
- kernel = g_realloc(kernel, kernel_size);
- setup_data = (struct setup_data *)(kernel + setup_data_offset);
- setup_data->next = cpu_to_le64(first_setup_data);
- first_setup_data = prot_addr + setup_data_offset;
- setup_data->type = cpu_to_le32(SETUP_RNG_SEED);
- setup_data->len = cpu_to_le32(RNG_SEED_LENGTH);
- qemu_guest_getrandom_nofail(setup_data->data, RNG_SEED_LENGTH);
- }
-
- /* Offset 0x250 is a pointer to the first setup_data link. */
- stq_p(header + 0x250, first_setup_data);
-
/*
* If we're starting an encrypted VM, it will be OVMF based, which uses the
* efi stub for booting and doesn't require any values to be placed in the
--
MST