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-rw-r--r--Documentation/virt/kvm/api.rst16
-rw-r--r--Documentation/virt/kvm/locking.rst2
-rw-r--r--Documentation/virt/kvm/s390/s390-diag.rst35
3 files changed, 38 insertions, 15 deletions
diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
index e32471977d0a..edc070c6e19b 100644
--- a/Documentation/virt/kvm/api.rst
+++ b/Documentation/virt/kvm/api.rst
@@ -8098,13 +8098,15 @@ KVM_X86_QUIRK_MWAIT_NEVER_UD_FAULTS By default, KVM emulates MONITOR/MWAIT (if
KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT is
disabled.
-KVM_X86_QUIRK_SLOT_ZAP_ALL By default, KVM invalidates all SPTEs in
- fast way for memslot deletion when VM type
- is KVM_X86_DEFAULT_VM.
- When this quirk is disabled or when VM type
- is other than KVM_X86_DEFAULT_VM, KVM zaps
- only leaf SPTEs that are within the range of
- the memslot being deleted.
+KVM_X86_QUIRK_SLOT_ZAP_ALL By default, for KVM_X86_DEFAULT_VM VMs, KVM
+ invalidates all SPTEs in all memslots and
+ address spaces when a memslot is deleted or
+ moved. When this quirk is disabled (or the
+ VM type isn't KVM_X86_DEFAULT_VM), KVM only
+ ensures the backing memory of the deleted
+ or moved memslot isn't reachable, i.e KVM
+ _may_ invalidate only SPTEs related to the
+ memslot.
=================================== ============================================
7.32 KVM_CAP_MAX_VCPU_ID
diff --git a/Documentation/virt/kvm/locking.rst b/Documentation/virt/kvm/locking.rst
index 20a9a37d1cdd..1bedd56e2fe3 100644
--- a/Documentation/virt/kvm/locking.rst
+++ b/Documentation/virt/kvm/locking.rst
@@ -136,7 +136,7 @@ For direct sp, we can easily avoid it since the spte of direct sp is fixed
to gfn. For indirect sp, we disabled fast page fault for simplicity.
A solution for indirect sp could be to pin the gfn, for example via
-kvm_vcpu_gfn_to_pfn_atomic, before the cmpxchg. After the pinning:
+gfn_to_pfn_memslot_atomic, before the cmpxchg. After the pinning:
- We have held the refcount of pfn; that means the pfn can not be freed and
be reused for another gfn.
diff --git a/Documentation/virt/kvm/s390/s390-diag.rst b/Documentation/virt/kvm/s390/s390-diag.rst
index ca85f030eb0b..3e4f9e3bef81 100644
--- a/Documentation/virt/kvm/s390/s390-diag.rst
+++ b/Documentation/virt/kvm/s390/s390-diag.rst
@@ -35,20 +35,24 @@ DIAGNOSE function codes not specific to KVM, please refer to the
documentation for the s390 hypervisors defining them.
-DIAGNOSE function code 'X'500' - KVM virtio functions
------------------------------------------------------
+DIAGNOSE function code 'X'500' - KVM functions
+----------------------------------------------
-If the function code specifies 0x500, various virtio-related functions
-are performed.
+If the function code specifies 0x500, various KVM-specific functions
+are performed, including virtio functions.
-General register 1 contains the virtio subfunction code. Supported
-virtio subfunctions depend on KVM's userspace. Generally, userspace
-provides either s390-virtio (subcodes 0-2) or virtio-ccw (subcode 3).
+General register 1 contains the subfunction code. Supported subfunctions
+depend on KVM's userspace. Regarding virtio subfunctions, generally
+userspace provides either s390-virtio (subcodes 0-2) or virtio-ccw
+(subcode 3).
Upon completion of the DIAGNOSE instruction, general register 2 contains
the function's return code, which is either a return code or a subcode
specific value.
+If the specified subfunction is not supported, a SPECIFICATION exception
+will be triggered.
+
Subcode 0 - s390-virtio notification and early console printk
Handled by userspace.
@@ -76,6 +80,23 @@ Subcode 3 - virtio-ccw notification
See also the virtio standard for a discussion of this hypercall.
+Subcode 4 - storage-limit
+ Handled by userspace.
+
+ After completion of the DIAGNOSE call, general register 2 will
+ contain the storage limit: the maximum physical address that might be
+ used for storage throughout the lifetime of the VM.
+
+ The storage limit does not indicate currently usable storage, it may
+ include holes, standby storage and areas reserved for other means, such
+ as memory hotplug or virtio-mem devices. Other interfaces for detecting
+ actually usable storage, such as SCLP, must be used in conjunction with
+ this subfunction.
+
+ Note that the storage limit can be larger, but never smaller than the
+ maximum storage address indicated by SCLP via the "maximum storage
+ increment" and the "increment size".
+
DIAGNOSE function code 'X'501 - KVM breakpoint
----------------------------------------------