[Qemu-devel] [PATCH v2] virtio-scsi: virtio_scsi_push_event() lacks VirtIOSCSIReq parsing

[Qemu-devel] [PATCH v2] virtio-scsi: virtio_scsi_push_event() lacks VirtIOSCSIReq parsing

[Greg Kurz]

Hotplug of a virtio scsi disk is currently broken: no disk appears in the
guest (verified with a fedora 20 host running a fedora 20 guest with KVM).
Bisect leeds to Paolo's patches to support any_layout, especially this
commit:

commit 36b15c79aa1bef5fe7543f9f2629b6413720bbfb
Author: Paolo Bonzini <pbonzini@redhat.com>
Date:   Tue Jun 10 16:21:18 2014 +0200

    virtio-scsi: start preparing for any_layout

It modifies virtio_scsi_pop_req() so that it is up to the callers to parse
the virtio scsi request. It seems that virtio_scsi_push_event() was not
modified accordingly...

This patch adds a call to virtio_scsi_parse_req(). It also drops some
sanity checks that are already performed by virtio_scsi_parse_req().

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
---

Changes in v2:
 - dropped now useless req->elem.out_num sanity check

 hw/scsi/virtio-scsi.c |    8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
index 04ecfa7..3fecdca 100644
--- a/hw/scsi/virtio-scsi.c
+++ b/hw/scsi/virtio-scsi.c
@@ -565,7 +565,6 @@ static void virtio_scsi_push_event(VirtIOSCSI *s, SCSIDevice *dev,
     VirtIOSCSIReq *req;
     VirtIOSCSIEvent *evt;
     VirtIODevice *vdev = VIRTIO_DEVICE(s);
-    int in_size;
 
     if (!(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) {
         return;
@@ -577,17 +576,12 @@ static void virtio_scsi_push_event(VirtIOSCSI *s, SCSIDevice *dev,
         return;
     }
 
-    if (req->elem.out_num) {
-        virtio_scsi_bad_req();
-    }
-
     if (s->events_dropped) {
         event |= VIRTIO_SCSI_T_EVENTS_MISSED;
         s->events_dropped = false;
     }
 
-    in_size = iov_size(req->elem.in_sg, req->elem.in_num);
-    if (in_size < sizeof(VirtIOSCSIEvent)) {
+    if (virtio_scsi_parse_req(req, 0, sizeof(VirtIOSCSIEvent))) {
         virtio_scsi_bad_req();
     }
 

Re: [Qemu-devel] [PATCH v2] virtio-scsi: virtio_scsi_push_event() lacks VirtIOSCSIReq parsing

[Paolo Bonzini]

Il 30/06/2014 17:33, Greg Kurz ha scritto:
> Hotplug of a virtio scsi disk is currently broken: no disk appears in the
> guest (verified with a fedora 20 host running a fedora 20 guest with KVM).
> Bisect leeds to Paolo's patches to support any_layout, especially this
> commit:
>
> commit 36b15c79aa1bef5fe7543f9f2629b6413720bbfb
> Author: Paolo Bonzini <pbonzini@redhat.com>
> Date:   Tue Jun 10 16:21:18 2014 +0200
>
>     virtio-scsi: start preparing for any_layout
>
> It modifies virtio_scsi_pop_req() so that it is up to the callers to parse
> the virtio scsi request. It seems that virtio_scsi_push_event() was not
> modified accordingly...
>
> This patch adds a call to virtio_scsi_parse_req(). It also drops some
> sanity checks that are already performed by virtio_scsi_parse_req().
>
> Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
> ---
>
> Changes in v2:
>  - dropped now useless req->elem.out_num sanity check
>
>  hw/scsi/virtio-scsi.c |    8 +-------
>  1 file changed, 1 insertion(+), 7 deletions(-)
>
> diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
> index 04ecfa7..3fecdca 100644
> --- a/hw/scsi/virtio-scsi.c
> +++ b/hw/scsi/virtio-scsi.c
> @@ -565,7 +565,6 @@ static void virtio_scsi_push_event(VirtIOSCSI *s, SCSIDevice *dev,
>      VirtIOSCSIReq *req;
>      VirtIOSCSIEvent *evt;
>      VirtIODevice *vdev = VIRTIO_DEVICE(s);
> -    int in_size;
>
>      if (!(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) {
>          return;
> @@ -577,17 +576,12 @@ static void virtio_scsi_push_event(VirtIOSCSI *s, SCSIDevice *dev,
>          return;
>      }
>
> -    if (req->elem.out_num) {
> -        virtio_scsi_bad_req();
> -    }
> -
>      if (s->events_dropped) {
>          event |= VIRTIO_SCSI_T_EVENTS_MISSED;
>          s->events_dropped = false;
>      }
>
> -    in_size = iov_size(req->elem.in_sg, req->elem.in_num);
> -    if (in_size < sizeof(VirtIOSCSIEvent)) {
> +    if (virtio_scsi_parse_req(req, 0, sizeof(VirtIOSCSIEvent))) {
>          virtio_scsi_bad_req();
>      }
>
>
>
>

Applying to scsi-next branch, thanks.

Paolo