mirrors/linux
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2026-04-29 07:02:29 -04:00
Code Issues Packages Projects Releases Wiki Activity

KVM: Close minor race in signal handling

Browse Source 
We need to check for signals inside the critical section, otherwise a
signal can be sent which we will not notice.  Also move the check
before entry, so that if the signal happens before the first entry,
we exit immediately instead of waiting for something to happen to the
guest.

Signed-off-by: Avi Kivity <avi@qumranet.com>
This commit is contained in:
Avi Kivity
2007-08-15 15:23:34 +03:00
parent 3090dd7377
commit 7e66f350cf
2 changed files with 22 additions and 20 deletions
Download Patch File Download Diff File Expand all files Collapse all files

19
drivers/kvm/svm.c
View File

@@ -1398,11 +1398,19 @@ static int svm_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
if (unlikely(r))
return r;
clgi();
if (signal_pending(current)) {
stgi();
++vcpu->stat.signal_exits;
post_kvm_run_save(svm, kvm_run);
kvm_run->exit_reason = KVM_EXIT_INTR;
return -EINTR;
}
if (!vcpu->mmio_read_completed)
do_interrupt_requests(svm, kvm_run);
clgi();
vcpu->guest_mode = 1;
if (vcpu->requests)
if (test_and_clear_bit(KVM_TLB_FLUSH, &vcpu->requests))
@@ -1582,13 +1590,6 @@ static int svm_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
r = handle_exit(svm, kvm_run);
if (r > 0) {
if (signal_pending(current)) {
++vcpu->stat.signal_exits;
post_kvm_run_save(svm, kvm_run);
kvm_run->exit_reason = KVM_EXIT_INTR;
return -EINTR;
}
if (dm_request_for_irq_injection(svm, kvm_run)) {
++vcpu->stat.request_irq_exits;
post_kvm_run_save(svm, kvm_run);

23
drivers/kvm/vmx.c
View File

@@ -2066,9 +2066,6 @@ static int vmx_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
preempt_disable();
if (!vcpu->mmio_read_completed)
do_interrupt_requests(vcpu, kvm_run);
vmx_save_host_state(vmx);
kvm_load_guest_fpu(vcpu);
@@ -2079,6 +2076,18 @@ static int vmx_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
local_irq_disable();
if (signal_pending(current)) {
local_irq_enable();
preempt_enable();
r = -EINTR;
kvm_run->exit_reason = KVM_EXIT_INTR;
++vcpu->stat.signal_exits;
goto out;
}
if (!vcpu->mmio_read_completed)
do_interrupt_requests(vcpu, kvm_run);
vcpu->guest_mode = 1;
if (vcpu->requests)
if (test_and_clear_bit(KVM_TLB_FLUSH, &vcpu->requests))
@@ -2227,14 +2236,6 @@ static int vmx_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
r = kvm_handle_exit(kvm_run, vcpu);
if (r > 0) {
/* Give scheduler a change to reschedule. */
if (signal_pending(current)) {
r = -EINTR;
kvm_run->exit_reason = KVM_EXIT_INTR;
++vcpu->stat.signal_exits;
goto out;
}
if (dm_request_for_irq_injection(vcpu, kvm_run)) {
r = -EINTR;
kvm_run->exit_reason = KVM_EXIT_INTR;