Fix storage attribute migration so that it does not fail for guests
with more than a few GB of RAM.
With such guests, the index in the buffer would go out of bounds,
usually by large amounts, thus receiving -EFAULT from the kernel.
Migration itself would be successful, but storage attributes would then
not be migrated completely.
This patch fixes the out of bounds access, and thus migration of all
storage attributes when the guest have large amounts of memory.
Cc: qemu-stable@nongnu.org
Signed-off-by: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Fixes: 903fd80b03
("s390x/migration: Storage attributes device")
Message-Id: <1516297904-18188-1-git-send-email-imbrenda@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
196 lines
6 KiB
C
196 lines
6 KiB
C
/*
|
|
* s390 storage attributes device -- KVM object
|
|
*
|
|
* Copyright 2016 IBM Corp.
|
|
* Author(s): Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
|
|
*
|
|
* This work is licensed under the terms of the GNU GPL, version 2 or (at
|
|
* your option) any later version. See the COPYING file in the top-level
|
|
* directory.
|
|
*/
|
|
|
|
#include "qemu/osdep.h"
|
|
#include "hw/boards.h"
|
|
#include "migration/qemu-file.h"
|
|
#include "hw/s390x/storage-attributes.h"
|
|
#include "qemu/error-report.h"
|
|
#include "sysemu/kvm.h"
|
|
#include "exec/ram_addr.h"
|
|
#include "cpu.h"
|
|
#include "kvm_s390x.h"
|
|
|
|
Object *kvm_s390_stattrib_create(void)
|
|
{
|
|
if (kvm_enabled() &&
|
|
kvm_check_extension(kvm_state, KVM_CAP_S390_CMMA_MIGRATION)) {
|
|
return object_new(TYPE_KVM_S390_STATTRIB);
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
static void kvm_s390_stattrib_instance_init(Object *obj)
|
|
{
|
|
KVMS390StAttribState *sas = KVM_S390_STATTRIB(obj);
|
|
|
|
sas->still_dirty = 0;
|
|
}
|
|
|
|
static int kvm_s390_stattrib_read_helper(S390StAttribState *sa,
|
|
uint64_t *start_gfn,
|
|
uint32_t count,
|
|
uint8_t *values,
|
|
uint32_t flags)
|
|
{
|
|
KVMS390StAttribState *sas = KVM_S390_STATTRIB(sa);
|
|
int r;
|
|
struct kvm_s390_cmma_log clog = {
|
|
.values = (uint64_t)values,
|
|
.start_gfn = *start_gfn,
|
|
.count = count,
|
|
.flags = flags,
|
|
};
|
|
|
|
r = kvm_vm_ioctl(kvm_state, KVM_S390_GET_CMMA_BITS, &clog);
|
|
if (r < 0) {
|
|
error_report("KVM_S390_GET_CMMA_BITS failed: %s", strerror(-r));
|
|
return r;
|
|
}
|
|
|
|
*start_gfn = clog.start_gfn;
|
|
sas->still_dirty = clog.remaining;
|
|
return clog.count;
|
|
}
|
|
|
|
static int kvm_s390_stattrib_get_stattr(S390StAttribState *sa,
|
|
uint64_t *start_gfn,
|
|
uint32_t count,
|
|
uint8_t *values)
|
|
{
|
|
return kvm_s390_stattrib_read_helper(sa, start_gfn, count, values, 0);
|
|
}
|
|
|
|
static int kvm_s390_stattrib_peek_stattr(S390StAttribState *sa,
|
|
uint64_t start_gfn,
|
|
uint32_t count,
|
|
uint8_t *values)
|
|
{
|
|
return kvm_s390_stattrib_read_helper(sa, &start_gfn, count, values,
|
|
KVM_S390_CMMA_PEEK);
|
|
}
|
|
|
|
static int kvm_s390_stattrib_set_stattr(S390StAttribState *sa,
|
|
uint64_t start_gfn,
|
|
uint32_t count,
|
|
uint8_t *values)
|
|
{
|
|
KVMS390StAttribState *sas = KVM_S390_STATTRIB(sa);
|
|
MachineState *machine = MACHINE(qdev_get_machine());
|
|
unsigned long max = machine->maxram_size / TARGET_PAGE_SIZE;
|
|
|
|
if (start_gfn + count > max) {
|
|
error_report("Out of memory bounds when setting storage attributes");
|
|
return -1;
|
|
}
|
|
if (!sas->incoming_buffer) {
|
|
sas->incoming_buffer = g_malloc0(max);
|
|
}
|
|
|
|
memcpy(sas->incoming_buffer + start_gfn, values, count);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void kvm_s390_stattrib_synchronize(S390StAttribState *sa)
|
|
{
|
|
KVMS390StAttribState *sas = KVM_S390_STATTRIB(sa);
|
|
MachineState *machine = MACHINE(qdev_get_machine());
|
|
unsigned long max = machine->maxram_size / TARGET_PAGE_SIZE;
|
|
unsigned long cx, len = 1 << 19;
|
|
int r;
|
|
struct kvm_s390_cmma_log clog = {
|
|
.flags = 0,
|
|
.mask = ~0ULL,
|
|
};
|
|
|
|
if (sas->incoming_buffer) {
|
|
for (cx = 0; cx + len <= max; cx += len) {
|
|
clog.start_gfn = cx;
|
|
clog.count = len;
|
|
clog.values = (uint64_t)(sas->incoming_buffer + cx);
|
|
r = kvm_vm_ioctl(kvm_state, KVM_S390_SET_CMMA_BITS, &clog);
|
|
if (r) {
|
|
error_report("KVM_S390_SET_CMMA_BITS failed: %s", strerror(-r));
|
|
return;
|
|
}
|
|
}
|
|
if (cx < max) {
|
|
clog.start_gfn = cx;
|
|
clog.count = max - cx;
|
|
clog.values = (uint64_t)(sas->incoming_buffer + cx);
|
|
r = kvm_vm_ioctl(kvm_state, KVM_S390_SET_CMMA_BITS, &clog);
|
|
if (r) {
|
|
error_report("KVM_S390_SET_CMMA_BITS failed: %s", strerror(-r));
|
|
}
|
|
}
|
|
g_free(sas->incoming_buffer);
|
|
sas->incoming_buffer = NULL;
|
|
}
|
|
}
|
|
|
|
static int kvm_s390_stattrib_set_migrationmode(S390StAttribState *sa, bool val)
|
|
{
|
|
struct kvm_device_attr attr = {
|
|
.group = KVM_S390_VM_MIGRATION,
|
|
.attr = val,
|
|
.addr = 0,
|
|
};
|
|
return kvm_vm_ioctl(kvm_state, KVM_SET_DEVICE_ATTR, &attr);
|
|
}
|
|
|
|
static long long kvm_s390_stattrib_get_dirtycount(S390StAttribState *sa)
|
|
{
|
|
KVMS390StAttribState *sas = KVM_S390_STATTRIB(sa);
|
|
uint8_t val[8];
|
|
|
|
kvm_s390_stattrib_peek_stattr(sa, 0, 1, val);
|
|
return sas->still_dirty;
|
|
}
|
|
|
|
static int kvm_s390_stattrib_get_active(S390StAttribState *sa)
|
|
{
|
|
return kvm_s390_cmma_active() && sa->migration_enabled;
|
|
}
|
|
|
|
static void kvm_s390_stattrib_class_init(ObjectClass *oc, void *data)
|
|
{
|
|
S390StAttribClass *sac = S390_STATTRIB_CLASS(oc);
|
|
DeviceClass *dc = DEVICE_CLASS(oc);
|
|
|
|
sac->get_stattr = kvm_s390_stattrib_get_stattr;
|
|
sac->peek_stattr = kvm_s390_stattrib_peek_stattr;
|
|
sac->set_stattr = kvm_s390_stattrib_set_stattr;
|
|
sac->set_migrationmode = kvm_s390_stattrib_set_migrationmode;
|
|
sac->get_dirtycount = kvm_s390_stattrib_get_dirtycount;
|
|
sac->synchronize = kvm_s390_stattrib_synchronize;
|
|
sac->get_active = kvm_s390_stattrib_get_active;
|
|
|
|
/* Reason: Can only be instantiated one time (internally) */
|
|
dc->user_creatable = false;
|
|
}
|
|
|
|
static const TypeInfo kvm_s390_stattrib_info = {
|
|
.name = TYPE_KVM_S390_STATTRIB,
|
|
.parent = TYPE_S390_STATTRIB,
|
|
.instance_init = kvm_s390_stattrib_instance_init,
|
|
.instance_size = sizeof(KVMS390StAttribState),
|
|
.class_init = kvm_s390_stattrib_class_init,
|
|
.class_size = sizeof(S390StAttribClass),
|
|
};
|
|
|
|
static void kvm_s390_stattrib_register_types(void)
|
|
{
|
|
type_register_static(&kvm_s390_stattrib_info);
|
|
}
|
|
|
|
type_init(kvm_s390_stattrib_register_types)
|