diff options
| author | Cornelia Huck <cohuck@redhat.com> | 2019-01-21 13:19:42 +0100 |
|---|---|---|
| committer | Michael S. Tsirkin <mst@redhat.com> | 2019-03-06 11:19:33 -0500 |
| commit | 8457fdfeb16d307b2acd502cb9224d03174294d2 (patch) | |
| tree | f2c824b52f777e2f747125a1a62848f5ce93e3d9 /Documentation/virtual | |
| parent | 59f3397ca7d3aa946a67d341d8126614b2f82b2a (diff) | |
virtio-ccw: diag 500 may return a negative cookie
If something goes wrong in the kvm io bus handling, the virtio-ccw
diagnose may return a negative error value in the cookie gpr.
Document this.
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'Documentation/virtual')
| -rw-r--r-- | Documentation/virtual/kvm/s390-diag.txt | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/Documentation/virtual/kvm/s390-diag.txt b/Documentation/virtual/kvm/s390-diag.txt index 48c4921794ed..7c52e5f8b210 100644 --- a/Documentation/virtual/kvm/s390-diag.txt +++ b/Documentation/virtual/kvm/s390-diag.txt @@ -68,7 +68,8 @@ Subcode 3 - virtio-ccw notification identifier, it is ignored. After completion of the DIAGNOSE call, general register 2 may contain - a 64bit identifier (in the kvm_io_bus cookie case). + a 64bit identifier (in the kvm_io_bus cookie case), or a negative + error value, if an internal error occurred. See also the virtio standard for a discussion of this hypercall. |