From d804232dc4a5400494442b04e0a066711f4f5b44 Mon Sep 17 00:00:00 2001 From: Greg Kurz Date: Thu, 28 Feb 2019 18:59:42 +0100 Subject: [PATCH] virtio-scsi: Fix build with gcc 9 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Build fails with gcc 9: CC ppc64-softmmu/hw/scsi/virtio-scsi.o hw/scsi/virtio-scsi.c: In function ‘virtio_scsi_do_tmf’: hw/scsi/virtio-scsi.c:265:39: error: taking address of packed member of ‘struct virtio_scsi_ctrl_tmf_req’ may result in an unaligned pointer value [-Werror=address-of-packed-member] 265 | virtio_tswap32s(VIRTIO_DEVICE(s), &req->req.tmf.subtype); | ^~~~~~~~~~~~~~~~~~~~~ cc1: all warnings being treated as errors All the fields in struct virtio_scsi_ctrl_tmf_req are naturally aligned, so we could in theory drop QEMU_PACKED. Unfortunately, the header file is imported from linux which already has the packed attribute. Trying to fix that in the update-linux-headers.sh script is likely to produce ugliness. Turn the call to virtio_tswap32s() into an assignment instead. Signed-off-by: Greg Kurz Message-Id: <155137678223.44753.5438092367451176318.stgit@bahia.lan> Signed-off-by: Paolo Bonzini --- hw/scsi/virtio-scsi.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c index ce99d288b0..839f120256 100644 --- a/hw/scsi/virtio-scsi.c +++ b/hw/scsi/virtio-scsi.c @@ -262,7 +262,13 @@ static int virtio_scsi_do_tmf(VirtIOSCSI *s, VirtIOSCSIReq *req) /* Here VIRTIO_SCSI_S_OK means "FUNCTION COMPLETE". */ req->resp.tmf.response = VIRTIO_SCSI_S_OK; - virtio_tswap32s(VIRTIO_DEVICE(s), &req->req.tmf.subtype); + /* + * req->req.tmf has the QEMU_PACKED attribute. Don't use virtio_tswap32s() + * to avoid compiler errors. + */ + req->req.tmf.subtype = + virtio_tswap32(VIRTIO_DEVICE(s), req->req.tmf.subtype); + switch (req->req.tmf.subtype) { case VIRTIO_SCSI_T_TMF_ABORT_TASK: case VIRTIO_SCSI_T_TMF_QUERY_TASK: