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* [PATCH v2 1/2] Revert "vhost-user: fix lost reconnect"
       [not found] <20240513071052.129581-1-fengli@smartx.com>
@ 2024-05-13  7:10 ` Li Feng
  2024-05-13  7:15   ` Michael S. Tsirkin
  2024-05-13  7:10 ` [PATCH v2 2/2] vhost-user: fix lost reconnect again Li Feng
  1 sibling, 1 reply; 3+ messages in thread
From: Li Feng @ 2024-05-13  7:10 UTC (permalink / raw)
  To: Michael S. Tsirkin, Raphael Norwitz, Kevin Wolf, Hanna Reitz,
	Paolo Bonzini, Fam Zheng, Alex Bennée,
	open list:Block layer core, open list:All patches CC here
  Cc: Yajun Wu, Stefano Garzarella

This reverts commit f02a4b8e6431598612466f76aac64ab492849abf.

Signed-off-by: Li Feng <fengli@smartx.com>
---
 hw/block/vhost-user-blk.c      |  2 +-
 hw/scsi/vhost-user-scsi.c      |  3 +--
 hw/virtio/vhost-user-base.c    |  2 +-
 hw/virtio/vhost-user.c         | 10 ++--------
 include/hw/virtio/vhost-user.h |  3 +--
 5 files changed, 6 insertions(+), 14 deletions(-)

diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c
index 9e6bbc6950..41d1ac3a5a 100644
--- a/hw/block/vhost-user-blk.c
+++ b/hw/block/vhost-user-blk.c
@@ -384,7 +384,7 @@ static void vhost_user_blk_event(void *opaque, QEMUChrEvent event)
     case CHR_EVENT_CLOSED:
         /* defer close until later to avoid circular close */
         vhost_user_async_close(dev, &s->chardev, &s->dev,
-                               vhost_user_blk_disconnect, vhost_user_blk_event);
+                               vhost_user_blk_disconnect);
         break;
     case CHR_EVENT_BREAK:
     case CHR_EVENT_MUX_IN:
diff --git a/hw/scsi/vhost-user-scsi.c b/hw/scsi/vhost-user-scsi.c
index a63b1f4948..48a59e020e 100644
--- a/hw/scsi/vhost-user-scsi.c
+++ b/hw/scsi/vhost-user-scsi.c
@@ -214,8 +214,7 @@ static void vhost_user_scsi_event(void *opaque, QEMUChrEvent event)
     case CHR_EVENT_CLOSED:
         /* defer close until later to avoid circular close */
         vhost_user_async_close(dev, &vs->conf.chardev, &vsc->dev,
-                               vhost_user_scsi_disconnect,
-                               vhost_user_scsi_event);
+                               vhost_user_scsi_disconnect);
         break;
     case CHR_EVENT_BREAK:
     case CHR_EVENT_MUX_IN:
diff --git a/hw/virtio/vhost-user-base.c b/hw/virtio/vhost-user-base.c
index a83167191e..4b54255682 100644
--- a/hw/virtio/vhost-user-base.c
+++ b/hw/virtio/vhost-user-base.c
@@ -254,7 +254,7 @@ static void vub_event(void *opaque, QEMUChrEvent event)
     case CHR_EVENT_CLOSED:
         /* defer close until later to avoid circular close */
         vhost_user_async_close(dev, &vub->chardev, &vub->vhost_dev,
-                               vub_disconnect, vub_event);
+                               vub_disconnect);
         break;
     case CHR_EVENT_BREAK:
     case CHR_EVENT_MUX_IN:
diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index cdf9af4a4b..c929097e87 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -2776,7 +2776,6 @@ typedef struct {
     DeviceState *dev;
     CharBackend *cd;
     struct vhost_dev *vhost;
-    IOEventHandler *event_cb;
 } VhostAsyncCallback;
 
 static void vhost_user_async_close_bh(void *opaque)
@@ -2791,10 +2790,7 @@ static void vhost_user_async_close_bh(void *opaque)
      */
     if (vhost->vdev) {
         data->cb(data->dev);
-    } else if (data->event_cb) {
-        qemu_chr_fe_set_handlers(data->cd, NULL, NULL, data->event_cb,
-                                 NULL, data->dev, NULL, true);
-   }
+    }
 
     g_free(data);
 }
@@ -2806,8 +2802,7 @@ static void vhost_user_async_close_bh(void *opaque)
  */
 void vhost_user_async_close(DeviceState *d,
                             CharBackend *chardev, struct vhost_dev *vhost,
-                            vu_async_close_fn cb,
-                            IOEventHandler *event_cb)
+                            vu_async_close_fn cb)
 {
     if (!runstate_check(RUN_STATE_SHUTDOWN)) {
         /*
@@ -2823,7 +2818,6 @@ void vhost_user_async_close(DeviceState *d,
         data->dev = d;
         data->cd = chardev;
         data->vhost = vhost;
-        data->event_cb = event_cb;
 
         /* Disable any further notifications on the chardev */
         qemu_chr_fe_set_handlers(chardev,
diff --git a/include/hw/virtio/vhost-user.h b/include/hw/virtio/vhost-user.h
index d7c09ffd34..324cd8663a 100644
--- a/include/hw/virtio/vhost-user.h
+++ b/include/hw/virtio/vhost-user.h
@@ -108,7 +108,6 @@ typedef void (*vu_async_close_fn)(DeviceState *cb);
 
 void vhost_user_async_close(DeviceState *d,
                             CharBackend *chardev, struct vhost_dev *vhost,
-                            vu_async_close_fn cb,
-                            IOEventHandler *event_cb);
+                            vu_async_close_fn cb);
 
 #endif
-- 
2.45.0



^ permalink raw reply related	[flat|nested] 3+ messages in thread

* [PATCH v2 2/2] vhost-user: fix lost reconnect again
       [not found] <20240513071052.129581-1-fengli@smartx.com>
  2024-05-13  7:10 ` [PATCH v2 1/2] Revert "vhost-user: fix lost reconnect" Li Feng
@ 2024-05-13  7:10 ` Li Feng
  1 sibling, 0 replies; 3+ messages in thread
From: Li Feng @ 2024-05-13  7:10 UTC (permalink / raw)
  To: Raphael Norwitz, Michael S. Tsirkin, Kevin Wolf, Hanna Reitz,
	Paolo Bonzini, Fam Zheng, Alex Bennée,
	open list:Block layer core, open list:All patches CC here
  Cc: Yajun Wu, Stefano Garzarella

When the vhost-user is reconnecting to the backend, and if the vhost-user fails
at the get_features in vhost_dev_init(), then the reconnect will fail
and it will not be retriggered forever.

The reason is:
When the vhost-user fail at get_features, the vhost_dev_cleanup will be called
immediately.

vhost_dev_cleanup calls 'memset(hdev, 0, sizeof(struct vhost_dev))'.

The reconnect path is:
vhost_user_blk_event
   vhost_user_async_close(.. vhost_user_blk_disconnect ..)
     qemu_chr_fe_set_handlers <----- clear the notifier callback
       schedule vhost_user_async_close_bh

The vhost->vdev is null, so the vhost_user_blk_disconnect will not be
called, then the event fd callback will not be reinstalled.

With this patch, the vhost_user_blk_disconnect will call the
vhost_dev_cleanup() again, it's safe.

In addition, the CLOSE event may occur in a scenario where connected is false.
At this time, the event handler will be cleared. We need to ensure that the
event handler can remain installed.

All vhost-user devices have this issue, including vhost-user-blk/scsi.

Fixes: 71e076a07d ("hw/virtio: generalise CHR_EVENT_CLOSED handling")

Signed-off-by: Li Feng <fengli@smartx.com>
---
 hw/block/vhost-user-blk.c   |  3 ++-
 hw/scsi/vhost-user-scsi.c   |  3 ++-
 hw/virtio/vhost-user-base.c |  3 ++-
 hw/virtio/vhost-user.c      | 10 +---------
 4 files changed, 7 insertions(+), 12 deletions(-)

diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c
index 41d1ac3a5a..c6842ced48 100644
--- a/hw/block/vhost-user-blk.c
+++ b/hw/block/vhost-user-blk.c
@@ -353,7 +353,7 @@ static void vhost_user_blk_disconnect(DeviceState *dev)
     VHostUserBlk *s = VHOST_USER_BLK(vdev);
 
     if (!s->connected) {
-        return;
+        goto done;
     }
     s->connected = false;
 
@@ -361,6 +361,7 @@ static void vhost_user_blk_disconnect(DeviceState *dev)
 
     vhost_dev_cleanup(&s->dev);
 
+done:
     /* Re-instate the event handler for new connections */
     qemu_chr_fe_set_handlers(&s->chardev, NULL, NULL, vhost_user_blk_event,
                              NULL, dev, NULL, true);
diff --git a/hw/scsi/vhost-user-scsi.c b/hw/scsi/vhost-user-scsi.c
index 48a59e020e..b49a11d23b 100644
--- a/hw/scsi/vhost-user-scsi.c
+++ b/hw/scsi/vhost-user-scsi.c
@@ -181,7 +181,7 @@ static void vhost_user_scsi_disconnect(DeviceState *dev)
     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
 
     if (!s->connected) {
-        return;
+        goto done;
     }
     s->connected = false;
 
@@ -189,6 +189,7 @@ static void vhost_user_scsi_disconnect(DeviceState *dev)
 
     vhost_dev_cleanup(&vsc->dev);
 
+done:
     /* Re-instate the event handler for new connections */
     qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL,
                              vhost_user_scsi_event, NULL, dev, NULL, true);
diff --git a/hw/virtio/vhost-user-base.c b/hw/virtio/vhost-user-base.c
index 4b54255682..11e72b1e3b 100644
--- a/hw/virtio/vhost-user-base.c
+++ b/hw/virtio/vhost-user-base.c
@@ -225,13 +225,14 @@ static void vub_disconnect(DeviceState *dev)
     VHostUserBase *vub = VHOST_USER_BASE(vdev);
 
     if (!vub->connected) {
-        return;
+        goto done;
     }
     vub->connected = false;
 
     vub_stop(vdev);
     vhost_dev_cleanup(&vub->vhost_dev);
 
+done:
     /* Re-instate the event handler for new connections */
     qemu_chr_fe_set_handlers(&vub->chardev,
                              NULL, NULL, vub_event,
diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index c929097e87..c407ea8939 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -2781,16 +2781,8 @@ typedef struct {
 static void vhost_user_async_close_bh(void *opaque)
 {
     VhostAsyncCallback *data = opaque;
-    struct vhost_dev *vhost = data->vhost;
 
-    /*
-     * If the vhost_dev has been cleared in the meantime there is
-     * nothing left to do as some other path has completed the
-     * cleanup.
-     */
-    if (vhost->vdev) {
-        data->cb(data->dev);
-    }
+    data->cb(data->dev);
 
     g_free(data);
 }
-- 
2.45.0



^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH v2 1/2] Revert "vhost-user: fix lost reconnect"
  2024-05-13  7:10 ` [PATCH v2 1/2] Revert "vhost-user: fix lost reconnect" Li Feng
@ 2024-05-13  7:15   ` Michael S. Tsirkin
  0 siblings, 0 replies; 3+ messages in thread
From: Michael S. Tsirkin @ 2024-05-13  7:15 UTC (permalink / raw)
  To: Li Feng
  Cc: Raphael Norwitz, Kevin Wolf, Hanna Reitz, Paolo Bonzini,
	Fam Zheng, Alex Bennée, open list:Block layer core,
	open list:All patches CC here, Yajun Wu, Stefano Garzarella

On Mon, May 13, 2024 at 03:10:47PM +0800, Li Feng wrote:
> This reverts commit f02a4b8e6431598612466f76aac64ab492849abf.
> 


include subject of reverted commit and motivation for the revert pls.


> Signed-off-by: Li Feng <fengli@smartx.com>
> ---
>  hw/block/vhost-user-blk.c      |  2 +-
>  hw/scsi/vhost-user-scsi.c      |  3 +--
>  hw/virtio/vhost-user-base.c    |  2 +-
>  hw/virtio/vhost-user.c         | 10 ++--------
>  include/hw/virtio/vhost-user.h |  3 +--
>  5 files changed, 6 insertions(+), 14 deletions(-)
> 
> diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c
> index 9e6bbc6950..41d1ac3a5a 100644
> --- a/hw/block/vhost-user-blk.c
> +++ b/hw/block/vhost-user-blk.c
> @@ -384,7 +384,7 @@ static void vhost_user_blk_event(void *opaque, QEMUChrEvent event)
>      case CHR_EVENT_CLOSED:
>          /* defer close until later to avoid circular close */
>          vhost_user_async_close(dev, &s->chardev, &s->dev,
> -                               vhost_user_blk_disconnect, vhost_user_blk_event);
> +                               vhost_user_blk_disconnect);
>          break;
>      case CHR_EVENT_BREAK:
>      case CHR_EVENT_MUX_IN:
> diff --git a/hw/scsi/vhost-user-scsi.c b/hw/scsi/vhost-user-scsi.c
> index a63b1f4948..48a59e020e 100644
> --- a/hw/scsi/vhost-user-scsi.c
> +++ b/hw/scsi/vhost-user-scsi.c
> @@ -214,8 +214,7 @@ static void vhost_user_scsi_event(void *opaque, QEMUChrEvent event)
>      case CHR_EVENT_CLOSED:
>          /* defer close until later to avoid circular close */
>          vhost_user_async_close(dev, &vs->conf.chardev, &vsc->dev,
> -                               vhost_user_scsi_disconnect,
> -                               vhost_user_scsi_event);
> +                               vhost_user_scsi_disconnect);
>          break;
>      case CHR_EVENT_BREAK:
>      case CHR_EVENT_MUX_IN:
> diff --git a/hw/virtio/vhost-user-base.c b/hw/virtio/vhost-user-base.c
> index a83167191e..4b54255682 100644
> --- a/hw/virtio/vhost-user-base.c
> +++ b/hw/virtio/vhost-user-base.c
> @@ -254,7 +254,7 @@ static void vub_event(void *opaque, QEMUChrEvent event)
>      case CHR_EVENT_CLOSED:
>          /* defer close until later to avoid circular close */
>          vhost_user_async_close(dev, &vub->chardev, &vub->vhost_dev,
> -                               vub_disconnect, vub_event);
> +                               vub_disconnect);
>          break;
>      case CHR_EVENT_BREAK:
>      case CHR_EVENT_MUX_IN:
> diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
> index cdf9af4a4b..c929097e87 100644
> --- a/hw/virtio/vhost-user.c
> +++ b/hw/virtio/vhost-user.c
> @@ -2776,7 +2776,6 @@ typedef struct {
>      DeviceState *dev;
>      CharBackend *cd;
>      struct vhost_dev *vhost;
> -    IOEventHandler *event_cb;
>  } VhostAsyncCallback;
>  
>  static void vhost_user_async_close_bh(void *opaque)
> @@ -2791,10 +2790,7 @@ static void vhost_user_async_close_bh(void *opaque)
>       */
>      if (vhost->vdev) {
>          data->cb(data->dev);
> -    } else if (data->event_cb) {
> -        qemu_chr_fe_set_handlers(data->cd, NULL, NULL, data->event_cb,
> -                                 NULL, data->dev, NULL, true);
> -   }
> +    }
>  
>      g_free(data);
>  }
> @@ -2806,8 +2802,7 @@ static void vhost_user_async_close_bh(void *opaque)
>   */
>  void vhost_user_async_close(DeviceState *d,
>                              CharBackend *chardev, struct vhost_dev *vhost,
> -                            vu_async_close_fn cb,
> -                            IOEventHandler *event_cb)
> +                            vu_async_close_fn cb)
>  {
>      if (!runstate_check(RUN_STATE_SHUTDOWN)) {
>          /*
> @@ -2823,7 +2818,6 @@ void vhost_user_async_close(DeviceState *d,
>          data->dev = d;
>          data->cd = chardev;
>          data->vhost = vhost;
> -        data->event_cb = event_cb;
>  
>          /* Disable any further notifications on the chardev */
>          qemu_chr_fe_set_handlers(chardev,
> diff --git a/include/hw/virtio/vhost-user.h b/include/hw/virtio/vhost-user.h
> index d7c09ffd34..324cd8663a 100644
> --- a/include/hw/virtio/vhost-user.h
> +++ b/include/hw/virtio/vhost-user.h
> @@ -108,7 +108,6 @@ typedef void (*vu_async_close_fn)(DeviceState *cb);
>  
>  void vhost_user_async_close(DeviceState *d,
>                              CharBackend *chardev, struct vhost_dev *vhost,
> -                            vu_async_close_fn cb,
> -                            IOEventHandler *event_cb);
> +                            vu_async_close_fn cb);
>  
>  #endif
> -- 
> 2.45.0



^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2024-05-13  7:16 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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     [not found] <20240513071052.129581-1-fengli@smartx.com>
2024-05-13  7:10 ` [PATCH v2 1/2] Revert "vhost-user: fix lost reconnect" Li Feng
2024-05-13  7:15   ` Michael S. Tsirkin
2024-05-13  7:10 ` [PATCH v2 2/2] vhost-user: fix lost reconnect again Li Feng

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