| Message ID | 20230824074115.93897-2-fengli@smartx.com |
|---|---|
| State | New |
| Headers | show |
| Series | Fix vhost reconnect issues | expand |
> On Aug 24, 2023, at 3:41 AM, Li Feng <fengli@smartx.com> wrote: > > 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 fails 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. > > All vhost-user devices have this issue, including vhost-user-blk/scsi. > > With this patch, if the vdev->vdev is null, the fd callback will still > be reinstalled. > > Fixes: 71e076a07d ("hw/virtio: generalise CHR_EVENT_CLOSED handling") > A couple of NITs, otherwise LGTM Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com> > 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-gpio.c | 2 +- > hw/virtio/vhost-user.c | 10 ++++++++-- > include/hw/virtio/vhost-user.h | 4 +++- > 5 files changed, 15 insertions(+), 6 deletions(-) > > diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c > index 3c69fa47d5..95c758200d 100644 > --- a/hw/block/vhost-user-blk.c > +++ b/hw/block/vhost-user-blk.c > @@ -391,7 +391,7 @@ 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_disconnect, vhost_user_blk_event); > 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 a7fa8e8df2..e931df9f5b 100644 > --- a/hw/scsi/vhost-user-scsi.c > +++ b/hw/scsi/vhost-user-scsi.c > @@ -236,7 +236,8 @@ 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_disconnect, > + vhost_user_scsi_event); > break; > case CHR_EVENT_BREAK: > case CHR_EVENT_MUX_IN: > diff --git a/hw/virtio/vhost-user-gpio.c b/hw/virtio/vhost-user-gpio.c > index d9979aa5db..04c2cc79f4 100644 > --- a/hw/virtio/vhost-user-gpio.c > +++ b/hw/virtio/vhost-user-gpio.c > @@ -283,7 +283,7 @@ static void vu_gpio_event(void *opaque, QEMUChrEvent event) > case CHR_EVENT_CLOSED: > /* defer close until later to avoid circular close */ > vhost_user_async_close(dev, &gpio->chardev, &gpio->vhost_dev, > - vu_gpio_disconnect); > + vu_gpio_disconnect, vu_gpio_event); > 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 8dcf049d42..9540766dd3 100644 > --- a/hw/virtio/vhost-user.c > +++ b/hw/virtio/vhost-user.c > @@ -2643,6 +2643,7 @@ typedef struct { > DeviceState *dev; > CharBackend *cd; > struct vhost_dev *vhost; > + IOEventHandler *event_cb; > } VhostAsyncCallback; > > static void vhost_user_async_close_bh(void *opaque) > @@ -2657,7 +2658,10 @@ 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); > } > @@ -2669,7 +2673,9 @@ 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) > + vu_async_close_fn cb, > + IOEventHandler *event_cb Nit: why the newline before the closing parenthesis? > + ) > { > if (!runstate_check(RUN_STATE_SHUTDOWN)) { > /* > diff --git a/include/hw/virtio/vhost-user.h b/include/hw/virtio/vhost-user.h > index 191216a74f..5fdc711d4e 100644 > --- a/include/hw/virtio/vhost-user.h > +++ b/include/hw/virtio/vhost-user.h > @@ -84,6 +84,8 @@ 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); > + vu_async_close_fn cb, > + IOEventHandler *event_cb Nit: ditto - don’t think we need this newline before ); > + ); > > #endif > -- > 2.41.0 >
> On 30 Aug 2023, at 6:11 AM, Raphael Norwitz <raphael.norwitz@nutanix.com> wrote: > > > >> On Aug 24, 2023, at 3:41 AM, Li Feng <fengli@smartx.com> wrote: >> >> 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 fails 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. >> >> All vhost-user devices have this issue, including vhost-user-blk/scsi. >> >> With this patch, if the vdev->vdev is null, the fd callback will still >> be reinstalled. >> >> Fixes: 71e076a07d ("hw/virtio: generalise CHR_EVENT_CLOSED handling") >> > > A couple of NITs, otherwise LGTM > > Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com <mailto:raphael.norwitz@nutanix.com>> > >> 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-gpio.c | 2 +- >> hw/virtio/vhost-user.c | 10 ++++++++-- >> include/hw/virtio/vhost-user.h | 4 +++- >> 5 files changed, 15 insertions(+), 6 deletions(-) >> >> diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c >> index 3c69fa47d5..95c758200d 100644 >> --- a/hw/block/vhost-user-blk.c >> +++ b/hw/block/vhost-user-blk.c >> @@ -391,7 +391,7 @@ 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_disconnect, vhost_user_blk_event); >> 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 a7fa8e8df2..e931df9f5b 100644 >> --- a/hw/scsi/vhost-user-scsi.c >> +++ b/hw/scsi/vhost-user-scsi.c >> @@ -236,7 +236,8 @@ 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_disconnect, >> + vhost_user_scsi_event); >> break; >> case CHR_EVENT_BREAK: >> case CHR_EVENT_MUX_IN: >> diff --git a/hw/virtio/vhost-user-gpio.c b/hw/virtio/vhost-user-gpio.c >> index d9979aa5db..04c2cc79f4 100644 >> --- a/hw/virtio/vhost-user-gpio.c >> +++ b/hw/virtio/vhost-user-gpio.c >> @@ -283,7 +283,7 @@ static void vu_gpio_event(void *opaque, QEMUChrEvent event) >> case CHR_EVENT_CLOSED: >> /* defer close until later to avoid circular close */ >> vhost_user_async_close(dev, &gpio->chardev, &gpio->vhost_dev, >> - vu_gpio_disconnect); >> + vu_gpio_disconnect, vu_gpio_event); >> 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 8dcf049d42..9540766dd3 100644 >> --- a/hw/virtio/vhost-user.c >> +++ b/hw/virtio/vhost-user.c >> @@ -2643,6 +2643,7 @@ typedef struct { >> DeviceState *dev; >> CharBackend *cd; >> struct vhost_dev *vhost; >> + IOEventHandler *event_cb; >> } VhostAsyncCallback; >> >> static void vhost_user_async_close_bh(void *opaque) >> @@ -2657,7 +2658,10 @@ 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); >> } >> @@ -2669,7 +2673,9 @@ 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) >> + vu_async_close_fn cb, >> + IOEventHandler *event_cb > > Nit: why the newline before the closing parenthesis? Acked. > >> + ) >> { >> if (!runstate_check(RUN_STATE_SHUTDOWN)) { >> /* >> diff --git a/include/hw/virtio/vhost-user.h b/include/hw/virtio/vhost-user.h >> index 191216a74f..5fdc711d4e 100644 >> --- a/include/hw/virtio/vhost-user.h >> +++ b/include/hw/virtio/vhost-user.h >> @@ -84,6 +84,8 @@ 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); >> + vu_async_close_fn cb, >> + IOEventHandler *event_cb > > Nit: ditto - don’t think we need this newline before ); Acked. > >> + ); >> >> #endif >> -- >> 2.41.0
diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c index 3c69fa47d5..95c758200d 100644 --- a/hw/block/vhost-user-blk.c +++ b/hw/block/vhost-user-blk.c @@ -391,7 +391,7 @@ 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_disconnect, vhost_user_blk_event); 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 a7fa8e8df2..e931df9f5b 100644 --- a/hw/scsi/vhost-user-scsi.c +++ b/hw/scsi/vhost-user-scsi.c @@ -236,7 +236,8 @@ 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_disconnect, + vhost_user_scsi_event); break; case CHR_EVENT_BREAK: case CHR_EVENT_MUX_IN: diff --git a/hw/virtio/vhost-user-gpio.c b/hw/virtio/vhost-user-gpio.c index d9979aa5db..04c2cc79f4 100644 --- a/hw/virtio/vhost-user-gpio.c +++ b/hw/virtio/vhost-user-gpio.c @@ -283,7 +283,7 @@ static void vu_gpio_event(void *opaque, QEMUChrEvent event) case CHR_EVENT_CLOSED: /* defer close until later to avoid circular close */ vhost_user_async_close(dev, &gpio->chardev, &gpio->vhost_dev, - vu_gpio_disconnect); + vu_gpio_disconnect, vu_gpio_event); 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 8dcf049d42..9540766dd3 100644 --- a/hw/virtio/vhost-user.c +++ b/hw/virtio/vhost-user.c @@ -2643,6 +2643,7 @@ typedef struct { DeviceState *dev; CharBackend *cd; struct vhost_dev *vhost; + IOEventHandler *event_cb; } VhostAsyncCallback; static void vhost_user_async_close_bh(void *opaque) @@ -2657,7 +2658,10 @@ 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); } @@ -2669,7 +2673,9 @@ 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) + vu_async_close_fn cb, + IOEventHandler *event_cb + ) { if (!runstate_check(RUN_STATE_SHUTDOWN)) { /* diff --git a/include/hw/virtio/vhost-user.h b/include/hw/virtio/vhost-user.h index 191216a74f..5fdc711d4e 100644 --- a/include/hw/virtio/vhost-user.h +++ b/include/hw/virtio/vhost-user.h @@ -84,6 +84,8 @@ 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); + vu_async_close_fn cb, + IOEventHandler *event_cb + ); #endif
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 fails 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. All vhost-user devices have this issue, including vhost-user-blk/scsi. With this patch, if the vdev->vdev is null, the fd callback will still be reinstalled. Fixes: 71e076a07d ("hw/virtio: generalise CHR_EVENT_CLOSED handling") 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-gpio.c | 2 +- hw/virtio/vhost-user.c | 10 ++++++++-- include/hw/virtio/vhost-user.h | 4 +++- 5 files changed, 15 insertions(+), 6 deletions(-)