diff options
authorDavid Gibson <>2012-11-23 16:08:44 +1100
committerDoug Goldstein <>2012-12-13 15:31:59 -0600
commit5e5cbe13a73bb99bc69de3e0925bd4964e56a2bb (patch)
parentiscsi: do not assume device is zero initialized (diff)
virtio-scsi: Fix some endian bugs with virtio-scsi
The virtio-scsi specification does not specify the correct endianness for fields in the request structure. It's therefore best to assume that it is "guest native" endian since that's the (stupid and poorly defined) norm in virtio. However, the qemu device for virtio-scsi has no byteswaps at all, and so will break if the guest has different endianness from the host. This patch fixes it by adding tswap() calls for the sense_len and resid fields in the request structure. In theory status_qualifier needs swaps as well, but that field is never actually touched. The tag field is a uint64_t, but since its value is completely arbitrary, it might as well be uint8_t[8] and so it does not need swapping. Cc: Paolo Bonzini <> Cc: Paul 'Rusty' Russell <> Signed-off-by: David Gibson <> Signed-off-by: Paolo Bonzini <> (cherry picked from commit 474ee55a18765e7de8f0b2cc00db5d26286bb24d) Signed-off-by: Michael Roth <> (cherry picked from commit ea08f3a4e25fe76d42a186152949516c2a63a46b)
1 files changed, 5 insertions, 3 deletions
diff --git a/hw/virtio-scsi.c b/hw/virtio-scsi.c
index c1b47a8f4..c6d529036 100644
--- a/hw/virtio-scsi.c
+++ b/hw/virtio-scsi.c
@@ -424,15 +424,17 @@ static void virtio_scsi_command_complete(SCSIRequest *r, uint32_t status,
size_t resid)
VirtIOSCSIReq *req = r->hba_private;
+ uint32_t sense_len;
req->resp.cmd->response = VIRTIO_SCSI_S_OK;
req->resp.cmd->status = status;
if (req->resp.cmd->status == GOOD) {
- req->resp.cmd->resid = resid;
+ req->resp.cmd->resid = tswap32(resid);
} else {
req->resp.cmd->resid = 0;
- req->resp.cmd->sense_len =
- scsi_req_get_sense(r, req->resp.cmd->sense, VIRTIO_SCSI_SENSE_SIZE);
+ sense_len = scsi_req_get_sense(r, req->resp.cmd->sense,
+ req->resp.cmd->sense_len = tswap32(sense_len);