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KVM: switch irq injection/acking data structures to irq_lock

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Protect irq injection/acking data structures with a separate irq_lock
mutex. This fixes the following deadlock:

CPU A                               CPU B
kvm_vm_ioctl_deassign_dev_irq()
  mutex_lock(&kvm->lock);            worker_thread()
  -> kvm_deassign_irq()                -> kvm_assigned_dev_interrupt_work_handler()
    -> deassign_host_irq()               mutex_lock(&kvm->lock);
      -> cancel_work_sync() [blocked]

[gleb: fix ia64 path]

Reported-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Marcelo Tosatti
2009-06-04 15:08:24 -03:00
committed by Avi Kivity
parent 60eead79ad
commit fa40a8214b
8 changed files with 58 additions and 30 deletions
Download Patch File Download Diff File Expand all files Collapse all files

19
arch/x86/kvm/x86.c
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@@ -2136,10 +2136,10 @@ long kvm_arch_vm_ioctl(struct file *filp,
goto out;
if (irqchip_in_kernel(kvm)) {
__s32 status;
mutex_lock(&kvm->lock);
mutex_lock(&kvm->irq_lock);
status = kvm_set_irq(kvm, KVM_USERSPACE_IRQ_SOURCE_ID,
irq_event.irq, irq_event.level);
mutex_unlock(&kvm->lock);
mutex_unlock(&kvm->irq_lock);
if (ioctl == KVM_IRQ_LINE_STATUS) {
irq_event.status = status;
if (copy_to_user(argp, &irq_event,
@@ -2385,12 +2385,11 @@ mmio:
*/
mutex_lock(&vcpu->kvm->lock);
mmio_dev = vcpu_find_mmio_dev(vcpu, gpa, bytes, 0);
mutex_unlock(&vcpu->kvm->lock);
if (mmio_dev) {
kvm_iodevice_read(mmio_dev, gpa, bytes, val);
mutex_unlock(&vcpu->kvm->lock);
return X86EMUL_CONTINUE;
}
mutex_unlock(&vcpu->kvm->lock);
vcpu->mmio_needed = 1;
vcpu->mmio_phys_addr = gpa;
@@ -2440,12 +2439,11 @@ mmio:
*/
mutex_lock(&vcpu->kvm->lock);
mmio_dev = vcpu_find_mmio_dev(vcpu, gpa, bytes, 1);
mutex_unlock(&vcpu->kvm->lock);
if (mmio_dev) {
kvm_iodevice_write(mmio_dev, gpa, bytes, val);
mutex_unlock(&vcpu->kvm->lock);
return X86EMUL_CONTINUE;
}
mutex_unlock(&vcpu->kvm->lock);
vcpu->mmio_needed = 1;
vcpu->mmio_phys_addr = gpa;
@@ -2768,7 +2766,6 @@ static void kernel_pio(struct kvm_io_device *pio_dev,
{
/* TODO: String I/O for in kernel device */
mutex_lock(&vcpu->kvm->lock);
if (vcpu->arch.pio.in)
kvm_iodevice_read(pio_dev, vcpu->arch.pio.port,
vcpu->arch.pio.size,
@@ -2777,7 +2774,6 @@ static void kernel_pio(struct kvm_io_device *pio_dev,
kvm_iodevice_write(pio_dev, vcpu->arch.pio.port,
vcpu->arch.pio.size,
pd);
mutex_unlock(&vcpu->kvm->lock);
}
static void pio_string_write(struct kvm_io_device *pio_dev,
@@ -2787,14 +2783,12 @@ static void pio_string_write(struct kvm_io_device *pio_dev,
void *pd = vcpu->arch.pio_data;
int i;
mutex_lock(&vcpu->kvm->lock);
for (i = 0; i < io->cur_count; i++) {
kvm_iodevice_write(pio_dev, io->port,
io->size,
pd);
pd += io->size;
}
mutex_unlock(&vcpu->kvm->lock);
}
static struct kvm_io_device *vcpu_find_pio_dev(struct kvm_vcpu *vcpu,
@@ -2831,7 +2825,9 @@ int kvm_emulate_pio(struct kvm_vcpu *vcpu, struct kvm_run *run, int in,
val = kvm_register_read(vcpu, VCPU_REGS_RAX);
memcpy(vcpu->arch.pio_data, &val, 4);
mutex_lock(&vcpu->kvm->lock);
pio_dev = vcpu_find_pio_dev(vcpu, port, size, !in);
mutex_unlock(&vcpu->kvm->lock);
if (pio_dev) {
kernel_pio(pio_dev, vcpu, vcpu->arch.pio_data);
complete_pio(vcpu);
@@ -2895,9 +2891,12 @@ int kvm_emulate_pio_string(struct kvm_vcpu *vcpu, struct kvm_run *run, int in,
vcpu->arch.pio.guest_gva = address;
mutex_lock(&vcpu->kvm->lock);
pio_dev = vcpu_find_pio_dev(vcpu, port,
vcpu->arch.pio.cur_count,
!vcpu->arch.pio.in);
mutex_unlock(&vcpu->kvm->lock);
if (!vcpu->arch.pio.in) {
/* string PIO write */
ret = pio_copy_data(vcpu);