mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 19:00:25 +00:00
KVM: s390: Lock kvm->srcu at the appropriate places
The kvm->srcu lock has to be held while accessing the memory of guests and during certain other actions. This patch now adds the locks to the __vcpu_run function so that all affected code is protected now (and additionally to the KVM_S390_STORE_STATUS ioctl, which can be called out-of-band and needs a separate lock). Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
parent
a76ccff6f5
commit
800c1065c3
3 changed files with 16 additions and 3 deletions
|
@ -107,14 +107,13 @@ static int __diag_ipl_functions(struct kvm_vcpu *vcpu)
|
||||||
|
|
||||||
static int __diag_virtio_hypercall(struct kvm_vcpu *vcpu)
|
static int __diag_virtio_hypercall(struct kvm_vcpu *vcpu)
|
||||||
{
|
{
|
||||||
int ret, idx;
|
int ret;
|
||||||
|
|
||||||
/* No virtio-ccw notification? Get out quickly. */
|
/* No virtio-ccw notification? Get out quickly. */
|
||||||
if (!vcpu->kvm->arch.css_support ||
|
if (!vcpu->kvm->arch.css_support ||
|
||||||
(vcpu->run->s.regs.gprs[1] != KVM_S390_VIRTIO_CCW_NOTIFY))
|
(vcpu->run->s.regs.gprs[1] != KVM_S390_VIRTIO_CCW_NOTIFY))
|
||||||
return -EOPNOTSUPP;
|
return -EOPNOTSUPP;
|
||||||
|
|
||||||
idx = srcu_read_lock(&vcpu->kvm->srcu);
|
|
||||||
/*
|
/*
|
||||||
* The layout is as follows:
|
* The layout is as follows:
|
||||||
* - gpr 2 contains the subchannel id (passed as addr)
|
* - gpr 2 contains the subchannel id (passed as addr)
|
||||||
|
@ -125,7 +124,6 @@ static int __diag_virtio_hypercall(struct kvm_vcpu *vcpu)
|
||||||
vcpu->run->s.regs.gprs[2],
|
vcpu->run->s.regs.gprs[2],
|
||||||
8, &vcpu->run->s.regs.gprs[3],
|
8, &vcpu->run->s.regs.gprs[3],
|
||||||
vcpu->run->s.regs.gprs[4]);
|
vcpu->run->s.regs.gprs[4]);
|
||||||
srcu_read_unlock(&vcpu->kvm->srcu, idx);
|
|
||||||
|
|
||||||
/*
|
/*
|
||||||
* Return cookie in gpr 2, but don't overwrite the register if the
|
* Return cookie in gpr 2, but don't overwrite the register if the
|
||||||
|
|
|
@ -436,6 +436,7 @@ int kvm_s390_handle_wait(struct kvm_vcpu *vcpu)
|
||||||
hrtimer_start(&vcpu->arch.ckc_timer, ktime_set (0, sltime) , HRTIMER_MODE_REL);
|
hrtimer_start(&vcpu->arch.ckc_timer, ktime_set (0, sltime) , HRTIMER_MODE_REL);
|
||||||
VCPU_EVENT(vcpu, 5, "enabled wait via clock comparator: %llx ns", sltime);
|
VCPU_EVENT(vcpu, 5, "enabled wait via clock comparator: %llx ns", sltime);
|
||||||
no_timer:
|
no_timer:
|
||||||
|
srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
|
||||||
spin_lock(&vcpu->arch.local_int.float_int->lock);
|
spin_lock(&vcpu->arch.local_int.float_int->lock);
|
||||||
spin_lock_bh(&vcpu->arch.local_int.lock);
|
spin_lock_bh(&vcpu->arch.local_int.lock);
|
||||||
add_wait_queue(&vcpu->wq, &wait);
|
add_wait_queue(&vcpu->wq, &wait);
|
||||||
|
@ -455,6 +456,8 @@ int kvm_s390_handle_wait(struct kvm_vcpu *vcpu)
|
||||||
remove_wait_queue(&vcpu->wq, &wait);
|
remove_wait_queue(&vcpu->wq, &wait);
|
||||||
spin_unlock_bh(&vcpu->arch.local_int.lock);
|
spin_unlock_bh(&vcpu->arch.local_int.lock);
|
||||||
spin_unlock(&vcpu->arch.local_int.float_int->lock);
|
spin_unlock(&vcpu->arch.local_int.float_int->lock);
|
||||||
|
vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
|
||||||
|
|
||||||
hrtimer_try_to_cancel(&vcpu->arch.ckc_timer);
|
hrtimer_try_to_cancel(&vcpu->arch.ckc_timer);
|
||||||
return 0;
|
return 0;
|
||||||
}
|
}
|
||||||
|
|
|
@ -752,11 +752,18 @@ static int __vcpu_run(struct kvm_vcpu *vcpu)
|
||||||
{
|
{
|
||||||
int rc, exit_reason;
|
int rc, exit_reason;
|
||||||
|
|
||||||
|
/*
|
||||||
|
* We try to hold kvm->srcu during most of vcpu_run (except when run-
|
||||||
|
* ning the guest), so that memslots (and other stuff) are protected
|
||||||
|
*/
|
||||||
|
vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
|
||||||
|
|
||||||
do {
|
do {
|
||||||
rc = vcpu_pre_run(vcpu);
|
rc = vcpu_pre_run(vcpu);
|
||||||
if (rc)
|
if (rc)
|
||||||
break;
|
break;
|
||||||
|
|
||||||
|
srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
|
||||||
/*
|
/*
|
||||||
* As PF_VCPU will be used in fault handler, between
|
* As PF_VCPU will be used in fault handler, between
|
||||||
* guest_enter and guest_exit should be no uaccess.
|
* guest_enter and guest_exit should be no uaccess.
|
||||||
|
@ -767,10 +774,12 @@ static int __vcpu_run(struct kvm_vcpu *vcpu)
|
||||||
exit_reason = sie64a(vcpu->arch.sie_block,
|
exit_reason = sie64a(vcpu->arch.sie_block,
|
||||||
vcpu->run->s.regs.gprs);
|
vcpu->run->s.regs.gprs);
|
||||||
kvm_guest_exit();
|
kvm_guest_exit();
|
||||||
|
vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
|
||||||
|
|
||||||
rc = vcpu_post_run(vcpu, exit_reason);
|
rc = vcpu_post_run(vcpu, exit_reason);
|
||||||
} while (!signal_pending(current) && !rc);
|
} while (!signal_pending(current) && !rc);
|
||||||
|
|
||||||
|
srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
|
||||||
return rc;
|
return rc;
|
||||||
}
|
}
|
||||||
|
|
||||||
|
@ -968,6 +977,7 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
|
||||||
{
|
{
|
||||||
struct kvm_vcpu *vcpu = filp->private_data;
|
struct kvm_vcpu *vcpu = filp->private_data;
|
||||||
void __user *argp = (void __user *)arg;
|
void __user *argp = (void __user *)arg;
|
||||||
|
int idx;
|
||||||
long r;
|
long r;
|
||||||
|
|
||||||
switch (ioctl) {
|
switch (ioctl) {
|
||||||
|
@ -981,7 +991,9 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
|
||||||
break;
|
break;
|
||||||
}
|
}
|
||||||
case KVM_S390_STORE_STATUS:
|
case KVM_S390_STORE_STATUS:
|
||||||
|
idx = srcu_read_lock(&vcpu->kvm->srcu);
|
||||||
r = kvm_s390_vcpu_store_status(vcpu, arg);
|
r = kvm_s390_vcpu_store_status(vcpu, arg);
|
||||||
|
srcu_read_unlock(&vcpu->kvm->srcu, idx);
|
||||||
break;
|
break;
|
||||||
case KVM_S390_SET_INITIAL_PSW: {
|
case KVM_S390_SET_INITIAL_PSW: {
|
||||||
psw_t psw;
|
psw_t psw;
|
||||||
|
|
Loading…
Reference in a new issue