--- zzzz-none-000/linux-3.10.107/Documentation/virtual/kvm/locking.txt	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/Documentation/virtual/kvm/locking.txt	2021-02-04 17:41:59.000000000 +0000
@@ -112,7 +112,7 @@
 
 In order to avoid this kind of issue, we always treat the spte as "volatile"
 if it can be updated out of mmu-lock, see spte_has_volatile_bits(), it means,
-the spte is always atomicly updated in this case.
+the spte is always atomically updated in this case.
 
 3): flush tlbs due to spte updated
 If the spte is updated from writable to readonly, we should flush all TLBs,
@@ -125,17 +125,21 @@
 function to update spte (present -> present).
 
 Since the spte is "volatile" if it can be updated out of mmu-lock, we always
-atomicly update the spte, the race caused by fast page fault can be avoided,
+atomically update the spte, the race caused by fast page fault can be avoided,
 See the comments in spte_has_volatile_bits() and mmu_spte_update().
 
 3. Reference
 ------------
 
 Name:		kvm_lock
-Type:		raw_spinlock
+Type:		spinlock_t
 Arch:		any
 Protects:	- vm_list
-		- hardware virtualization enable/disable
+
+Name:		kvm_count_lock
+Type:		raw_spinlock_t
+Arch:		any
+Protects:	- hardware virtualization enable/disable
 Comment:	'raw' because hardware enabling/disabling must be atomic /wrt
 		migration.
 
@@ -151,3 +155,26 @@
 Arch:		any
 Protects:	-shadow page/shadow tlb entry
 Comment:	it is a spinlock since it is used in mmu notifier.
+
+Name:		kvm->srcu
+Type:		srcu lock
+Arch:		any
+Protects:	- kvm->memslots
+		- kvm->buses
+Comment:	The srcu read lock must be held while accessing memslots (e.g.
+		when using gfn_to_* functions) and while accessing in-kernel
+		MMIO/PIO address->device structure mapping (kvm->buses).
+		The srcu index can be stored in kvm_vcpu->srcu_idx per vcpu
+		if it is needed by multiple functions.
+
+Name:		blocked_vcpu_on_cpu_lock
+Type:		spinlock_t
+Arch:		x86
+Protects:	blocked_vcpu_on_cpu
+Comment:	This is a per-CPU lock and it is used for VT-d posted-interrupts.
+		When VT-d posted-interrupts is supported and the VM has assigned
+		devices, we put the blocked vCPU on the list blocked_vcpu_on_cpu
+		protected by blocked_vcpu_on_cpu_lock, when VT-d hardware issues
+		wakeup notification event since external interrupts from the
+		assigned devices happens, we will find the vCPU on the list to
+		wakeup.