OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

KVM: Close minor race in signal handling 

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
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

19
drivers/kvm/svm.c
View File

@ -1398,11 +1398,19 @@ again:
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 @@ again:
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 @@ again:
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 @@ again:
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 @@ again:
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;