3.16.64-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Christoffer Dall <christoffer.dall@xxxxxxxxxx>
commit 023e9fddc3616b005c3753fc1bb6526388cd7a30 upstream.
As we are about to hold the kvm->lock during the create operation on KVM
devices, we should move the call to xics_debugfs_init into its own
function, since holding a mutex over extended amounts of time might not
be a good idea.
Introduce an init operation on the kvm_device_ops struct which cannot
fail and call this, if configured, after the device has been created.
Signed-off-by: Christoffer Dall <christoffer.dall@xxxxxxxxxx>
Reviewed-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Radim Krčmář <rkrcmar@xxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
arch/powerpc/kvm/book3s_xics.c | 10 ++++++++--
include/linux/kvm_host.h | 6 ++++++
virt/kvm/kvm_main.c | 3 +++
3 files changed, 17 insertions(+), 2 deletions(-)
--- a/arch/powerpc/kvm/book3s_xics.c
+++ b/arch/powerpc/kvm/book3s_xics.c
@@ -1251,8 +1251,6 @@ static int kvmppc_xics_create(struct kvm
return ret;
}
- xics_debugfs_init(xics);
-
#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
if (cpu_has_feature(CPU_FTR_ARCH_206)) {
/* Enable real mode support */
@@ -1264,9 +1262,17 @@ static int kvmppc_xics_create(struct kvm
return 0;
}
+static void kvmppc_xics_init(struct kvm_device *dev)
+{
+ struct kvmppc_xics *xics = (struct kvmppc_xics *)dev->private;
+
+ xics_debugfs_init(xics);
+}
+
struct kvm_device_ops kvm_xics_ops = {
.name = "kvm-xics",
.create = kvmppc_xics_create,
+ .init = kvmppc_xics_init,
.destroy = kvmppc_xics_free,
.set_attr = xics_set_attr,
.get_attr = xics_get_attr,
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1062,6 +1062,12 @@ struct kvm_device_ops {
int (*create)(struct kvm_device *dev, u32 type);
/*
+ * init is called after create if create is successful and is called
+ * outside of holding kvm->lock.
+ */
+ void (*init)(struct kvm_device *dev);
+
+ /*
* Destroy is responsible for freeing dev.
*
* Destroy may be called before or after destructors are called
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -2328,6 +2328,9 @@ static int kvm_ioctl_create_device(struc
return ret;
}
+ if (ops->init)
+ ops->init(dev);
+
ret = anon_inode_getfd(ops->name, &kvm_device_fops, dev, O_RDWR | O_CLOEXEC);
if (ret < 0) {
ops->destroy(dev);
