From mboxrd@z Thu Jan 1 00:00:00 1970 From: Cornelia Huck Subject: [PULL 1/1] virtio-ccw: diag 500 may return a negative cookie Date: Wed, 19 Dec 2018 11:14:14 +0100 Message-ID: <20181219101414.13901-2-cohuck@redhat.com> References: <20181219101414.13901-1-cohuck@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20181219101414.13901-1-cohuck@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: "Michael S . Tsirkin" Cc: linux-s390@vger.kernel.org, kvm@vger.kernel.org, Cornelia Huck , virtualization@lists.linux-foundation.org, Halil Pasic List-Id: virtualization@lists.linuxfoundation.org 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 Signed-off-by: Cornelia Huck --- Documentation/virtual/kvm/s390-diag.txt | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) 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. -- 2.17.2