Describe the semantics of the new KVM_S390_MEMOP_F_CMPXCHG flag for
absolute vm write memops which allows user space to perform (storage key
checked) cmpxchg operations on guest memory.
Signed-off-by: Janis Schoetterl-Glausch <scgl@xxxxxxxxxxxxx>
---
Documentation/virt/kvm/api.rst | 29 ++++++++++++++++++++++++++---
1 file changed, 26 insertions(+), 3 deletions(-)
diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
index 0a67cb738013..d09d7223c2a6 100644
--- a/Documentation/virt/kvm/api.rst
+++ b/Documentation/virt/kvm/api.rst
@@ -3736,7 +3736,8 @@ The fields in each entry are defined as follows:
:Parameters: struct kvm_s390_mem_op (in)
:Returns: = 0 on success,
< 0 on generic error (e.g. -EFAULT or -ENOMEM),
- > 0 if an exception occurred while walking the page tables
+ 16 bit program exception code if the access causes such an exception,
+ other code > 0xffff with special meaning.