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-rw-r--r--virtio-v1.0-wd01-part1-specification.txt14
1 files changed, 7 insertions, 7 deletions
diff --git a/virtio-v1.0-wd01-part1-specification.txt b/virtio-v1.0-wd01-part1-specification.txt
index f8751ad..d65e8f2 100644
--- a/virtio-v1.0-wd01-part1-specification.txt
+++ b/virtio-v1.0-wd01-part1-specification.txt
@@ -858,7 +858,7 @@ When used through the legacy interface, the virtio header looks as follows:
If MSI-X is enabled for the device, two additional fields
-immediately follow this header:[5]
+immediately follow this header:
+------------++----------------+--------+
@@ -871,6 +871,12 @@ immediately follow this header:[5]
| (MSI-X) || Vector | Vector |
+------------++----------------+--------+
+Note: When MSI-X capability is enabled, device specific configuration starts at
+byte offset 24 in virtio header structure. When MSI-X capability is not
+enabled, device specific configuration starts at byte offset 20 in virtio
+header. ie. once you enable MSI-X on the device, the other fields move.
+If you turn it off again, they move back!
+
Immediately following these general headers, there may be
device-specific headers:
@@ -3388,12 +3394,6 @@ the non-PCI implementations (currently lguest and S/390).
This is only allowed if the driver does not use any features
which would alter this early use of the device.
-[5] When MSI-X capability is enabled, device specific configuration starts at
-byte offset 24 in virtio header structure. When MSI-X capability is not
-enabled, device specific configuration starts at byte offset 20 in virtio
-header. ie. once you enable MSI-X on the device, the other fields move.
-If you turn it off again, they move back!
-
[6] The 4096 is based on the x86 page size, but it's also large
enough to ensure that the separate parts of the virtqueue are on
separate cache lines.