From 56492eaf88fab18f4ee685cd34b9aacff5dc43b9 Mon Sep 17 00:00:00 2001 From: rusty Date: Fri, 31 Jan 2014 04:06:50 +0000 Subject: Feedback #4: Haggai Eran's VIRTIO_RING_F_INDIRECT_DESC fix. Signed-off-by: Rusty Russell git-svn-id: https://tools.oasis-open.org/version-control/svn/virtio@200 0c8fb4dd-22a2-4bb5-bc14-6c75a5f43652 --- feedback/4.txt | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) create mode 100644 feedback/4.txt (limited to 'feedback/4.txt') diff --git a/feedback/4.txt b/feedback/4.txt new file mode 100644 index 0000000..eaedb17 --- /dev/null +++ b/feedback/4.txt @@ -0,0 +1,48 @@ +Document: virtio-v1.0-csprd01 +Number: 4 +Date: Tue, 28 Jan 2014 10:03:51 +0200 +Link to Mail: https://lists.oasis-open.org/archives/virtio-comment/201401/msg00045.html +Commenter name: Haggai Eran +Decision: + +In Section 2.4.5, "The Virtqueue Available Ring", it says: + +> If the VIRTIO_RING_F_INDIRECT_DESC feature bit is not negotiated, the +> “flags” field offers a crude interrupt + +Shouldn't it be VIRTIO_RING_F_EVENT_IDX instead of +VIRTIO_RING_F_INDIRECT_DESC? +The next paragraph says: + +> Otherwise, if the VIRTIO_RING_F_EVENT_IDX feature bit is negotiated, the +> driver MUST set the "flags" field + +The same question also applies to Section 2.4.6. + +Proposal: + +diff --git a/content.tex b/content.tex +index 374bc02..f048a88 100644 +--- a/content.tex ++++ b/content.tex +@@ -425,7 +425,7 @@ written by the driver and read by the device. + The “idx” field indicates where the driver would put the next descriptor + entry in the ring (modulo the queue size). This starts at 0, and increases. + +-If the VIRTIO_RING_F_INDIRECT_DESC feature bit is not negotiated, the ++If the VIRTIO_RING_F_EVENT_IDX feature bit is not negotiated, the + “flags” field offers a crude interrupt control mechanism. The driver + MUST set this to 0 or 1: 1 indicates that the device SHOULD NOT send + an interrupt when it consumes a descriptor chain from the available +@@ -473,7 +473,7 @@ for drivers using untrusted buffers: if you do not know exactly + how much has been written by the device, you usually have to zero + the buffer to ensure no data leakage occurs. + +-If the VIRTIO_RING_F_INDIRECT_DESC feature bit is not negotiated, the ++If the VIRTIO_RING_F_EVENT_IDX feature bit is not negotiated, the + “flags” field offers a crude interrupt control mechanism. The driver + MUST initialize this to 0, the device MUST set this to 0 or 1: 1 + indicates that the driver SHOULD NOT send an notification when it adds + +Decision: + -- cgit v1.2.3