This is a note to let you know that I've just added the patch titled
KVM: x86: Move guts of kvm_arch_init() to standalone helper
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
kvm-x86-move-guts-of-kvm_arch_init-to-standalone-hel.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit d09c939d196cdeb3c83d11c761a6644f86b37fd2
Author: Sean Christopherson <seanjc@xxxxxxxxxx>
Date: Wed Nov 30 23:08:57 2022 +0000
KVM: x86: Move guts of kvm_arch_init() to standalone helper
[ Upstream commit 4f8396b96a9fc672964842fe7adbe8ddca8a3adf ]
Move the guts of kvm_arch_init() to a new helper, kvm_x86_vendor_init(),
so that VMX can do _all_ arch and vendor initialization before calling
kvm_init(). Calling kvm_init() must be the _very_ last step during init,
as kvm_init() exposes /dev/kvm to userspace, i.e. allows creating VMs.
No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Message-Id: <20221130230934.1014142-14-seanjc@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Stable-dep-of: e32b120071ea ("KVM: VMX: Do _all_ initialization before exposing /dev/kvm to userspace")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index f05ebaa26f0ff..ef8cabfbe8540 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1695,6 +1695,9 @@ extern struct kvm_x86_ops kvm_x86_ops;
#define KVM_X86_OP_OPTIONAL_RET0 KVM_X86_OP
#include <asm/kvm-x86-ops.h>
+int kvm_x86_vendor_init(struct kvm_x86_init_ops *ops);
+void kvm_x86_vendor_exit(void);
+
#define __KVM_HAVE_ARCH_VM_ALLOC
static inline struct kvm *kvm_arch_alloc_vm(void)
{
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index bfe93a1c4f92e..3629dd979667c 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -5080,15 +5080,34 @@ static struct kvm_x86_init_ops svm_init_ops __initdata = {
static int __init svm_init(void)
{
+ int r;
+
__unused_size_checks();
- return kvm_init(&svm_init_ops, sizeof(struct vcpu_svm),
- __alignof__(struct vcpu_svm), THIS_MODULE);
+ r = kvm_x86_vendor_init(&svm_init_ops);
+ if (r)
+ return r;
+
+ /*
+ * Common KVM initialization _must_ come last, after this, /dev/kvm is
+ * exposed to userspace!
+ */
+ r = kvm_init(&svm_init_ops, sizeof(struct vcpu_svm),
+ __alignof__(struct vcpu_svm), THIS_MODULE);
+ if (r)
+ goto err_kvm_init;
+
+ return 0;
+
+err_kvm_init:
+ kvm_x86_vendor_exit();
+ return r;
}
static void __exit svm_exit(void)
{
kvm_exit();
+ kvm_x86_vendor_exit();
}
module_init(svm_init)
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index d3d84563a7f9c..81a23ae4f872b 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -8464,6 +8464,7 @@ static void vmx_exit(void)
#endif
kvm_exit();
+ kvm_x86_vendor_exit();
vmx_cleanup_l1d_flush();
@@ -8508,23 +8509,25 @@ static int __init vmx_init(void)
}
#endif
+ r = kvm_x86_vendor_init(&vmx_init_ops);
+ if (r)
+ return r;
+
r = kvm_init(&vmx_init_ops, sizeof(struct vcpu_vmx),
__alignof__(struct vcpu_vmx), THIS_MODULE);
if (r)
- return r;
+ goto err_kvm_init;
/*
- * Must be called after kvm_init() so enable_ept is properly set
+ * Must be called after common x86 init so enable_ept is properly set
* up. Hand the parameter mitigation value in which was stored in
* the pre module init parser. If no parameter was given, it will
* contain 'auto' which will be turned into the default 'cond'
* mitigation mode.
*/
r = vmx_setup_l1d_flush(vmentry_l1d_flush_param);
- if (r) {
- vmx_exit();
- return r;
- }
+ if (r)
+ goto err_l1d_flush;
vmx_setup_fb_clear_ctrl();
@@ -8549,5 +8552,11 @@ static int __init vmx_init(void)
allow_smaller_maxphyaddr = true;
return 0;
+
+err_l1d_flush:
+ vmx_exit();
+err_kvm_init:
+ kvm_x86_vendor_exit();
+ return r;
}
module_init(vmx_init);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 68827b8dc37a5..ab09d292bdede 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9351,7 +9351,16 @@ static struct notifier_block pvclock_gtod_notifier = {
int kvm_arch_init(void *opaque)
{
- struct kvm_x86_init_ops *ops = opaque;
+ return 0;
+}
+
+void kvm_arch_exit(void)
+{
+
+}
+
+int kvm_x86_vendor_init(struct kvm_x86_init_ops *ops)
+{
u64 host_pat;
int r;
@@ -9441,8 +9450,9 @@ int kvm_arch_init(void *opaque)
kmem_cache_destroy(x86_emulator_cache);
return r;
}
+EXPORT_SYMBOL_GPL(kvm_x86_vendor_init);
-void kvm_arch_exit(void)
+void kvm_x86_vendor_exit(void)
{
#ifdef CONFIG_X86_64
if (hypervisor_is_type(X86_HYPER_MS_HYPERV))
@@ -9468,6 +9478,7 @@ void kvm_arch_exit(void)
WARN_ON(static_branch_unlikely(&kvm_xen_enabled.key));
#endif
}
+EXPORT_SYMBOL_GPL(kvm_x86_vendor_exit);
static int __kvm_emulate_halt(struct kvm_vcpu *vcpu, int state, int reason)
{
