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authorCornelia Huck <cohuck@redhat.com>2019-01-21 13:19:42 +0100
committerMichael S. Tsirkin <mst@redhat.com>2019-03-06 17:19:33 +0100
commit8457fdfeb16d307b2acd502cb9224d03174294d2 (patch)
treef2c824b52f777e2f747125a1a62848f5ce93e3d9 /Documentation/virtual/kvm
parentvirtio_balloon: remove the unnecessary 0-initialization (diff)
downloadlinux-8457fdfeb16d307b2acd502cb9224d03174294d2.tar.xz
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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/kvm')
-rw-r--r--Documentation/virtual/kvm/s390-diag.txt3
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.