Changeset 97530 in vbox

Timestamp:

Nov 14, 2022 12:24:20 PM (2 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

154556

Message:

Devices/VirtioCore.cpp: Add workaround for the legacy virtio-net driver included in FreeBSD up to 12.3 violating the specification leaving the device in a non working state, ticketref:21201

Location:

trunk

Files:

• doc/manual/user_ChangeLogImpl.xml (modified) (1 diff)
• src/VBox/Devices/VirtIO/VirtioCore.cpp (modified) (2 diffs)

trunk/doc/manual/user_ChangeLogImpl.xml

@@ -104 +104 @@
 
       <listitem>
+        <para>virtio-net: Workaround a bug in the virtio-net driver included in FreeBSD version up to 12.3
+          which renders the device non functional (bug #21201)</para>
+      </listitem>
+
+      <listitem>
         <para>Storage: Fixed I/O errors with the VirtioSCSI controller when the host I/O cache is enabled (bug #19717)</para>
       </listitem>

trunk/src/VBox/Devices/VirtIO/VirtioCore.cpp

@@ -177 +177 @@
                                 uint32_t idxDesc, PVIRTQ_DESC_T pDesc)
 {
-    AssertMsg(IS_DRIVER_OK(pVirtio), ("Called with guest driver not ready\n"));
+    /*
+     * Shut up assertion for legacy virtio-net driver in FreeBSD up to 12.3 (see virtioCoreR3VirtqUsedBufPut()
+     * for more information).
+     */
+    AssertMsg(   IS_DRIVER_OK(pVirtio)
+              || (   pVirtio->fLegacyDriver
+                  && pVirtq->GCPhysVirtqDesc),
+              ("Called with guest driver not ready\n"));
     uint16_t const cVirtqItems = RT_MAX(pVirtq->uQueueSize, 1); /* Make sure to avoid div-by-zero. */
 
@@ -995 +1002 @@
     Assert(pVirtqBuf->cRefs > 0);
 
-    AssertMsgReturn(IS_DRIVER_OK(pVirtio), ("Guest driver not in ready state.\n"), VERR_INVALID_STATE);
+    /*
+     * Workaround for a bug in FreeBSD's virtio-net driver up until 12.3 which supports only the legacy style devive.
+     * When the device is re-initialized from the driver it violates the spec and posts commands to the control queue
+     * before setting the DRIVER_OK flag, breaking the following check and rendering the device non-functional.
+     * The queues are properly set up at this stage however so no real harm is done and we can safely continue here,
+     * for the legacy device only of course after making sure the queue is properly set up.
+     */
+    AssertMsgReturn(   IS_DRIVER_OK(pVirtio)
+                    || (   pVirtio->fLegacyDriver
+                        && pVirtq->GCPhysVirtqDesc),
+                    ("Guest driver not in ready state.\n"), VERR_INVALID_STATE);
 
     Log6Func(("    Copying device data to %s, [desc:%u → used ring:%u]\n",