Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

x86 and SCSI fixes.  I left out the APIC device model
patches, pending confirmation from the submitter that they really
fix QNX.

# gpg: Signature made Thu 13 Nov 2014 15:13:38 GMT using RSA key ID 78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4  E2F7 7E15 100C CD36 69B1
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* remotes/bonzini/tags/for-upstream:
  acpi: accurate overflow check
  smbios: change 'ram_addr_t' variables to 'uint64_t'
  kvmclock: Add comment explaining why we need cpu_clean_all_dirty()
  target-i386: fix Coverity complaints about overflows
  apic_common: migrate missing fields
  target-i386: eliminate dead code and hoist common code out of "if"
  virtio-scsi: Fix comment for VirtIOSCSIReq
  virtio-scsi: dataplane: suppress guest notification
  esp: Do not overwrite ESP_TCHI after reset
  virtio-scsi: dataplane: fix allocation for 'cmd_vrings'
  esp: fix coding standards
  virtio-scsi: work around bug in old BIOSes
  esp-pci: fixup deadlock with linux

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 17 insertions, 0 deletions

diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
index fdcacfd79a..ef485508b1 100644
--- a/hw/scsi/virtio-scsi.c
+++ b/hw/scsi/virtio-scsi.c
@@ -118,6 +118,7 @@ static size_t qemu_sgl_concat(VirtIOSCSIReq *req, struct iovec *iov,
 static int virtio_scsi_parse_req(VirtIOSCSIReq *req,
                                  unsigned req_size, unsigned resp_size)
 {
+    VirtIODevice *vdev = (VirtIODevice *) req->dev;
     size_t in_size, out_size;
 
     if (iov_to_buf(req->elem.out_sg, req->elem.out_num, 0,
@@ -130,8 +131,24 @@ static int virtio_scsi_parse_req(VirtIOSCSIReq *req,
                               resp_size) < resp_size) {
         return -EINVAL;
     }
+
     req->resp_size = resp_size;
 
+    /* Old BIOSes left some padding by mistake after the req_size/resp_size.
+     * As a workaround, always consider the first buffer as the virtio-scsi
+     * request/response, making the payload start at the second element
+     * of the iovec.
+     *
+     * The actual length of the response header, stored in req->resp_size,
+     * does not change.
+     *
+     * TODO: always disable this workaround for virtio 1.0 devices.
+     */
+    if ((vdev->guest_features & VIRTIO_F_ANY_LAYOUT) == 0) {
+        req_size = req->elem.out_sg[0].iov_len;
+        resp_size = req->elem.in_sg[0].iov_len;
+    }
+
     out_size = qemu_sgl_concat(req, req->elem.out_sg,
                                &req->elem.out_addr[0], req->elem.out_num,
                                req_size);