[PATCH v2 0/2] xen/xenbus: better handle backend crash

[PATCH v2 0/2] xen/xenbus: better handle backend crash

[Juergen Gross]

This small series fixes PV-device frontend side handling in case the
backend crashed and has come up again.

The old device will be discarded and the replacement can be used
instead.

Changes in V2:
- fixed one comment related build warning

Juergen Gross (2):
  xenbus: add xenbus_device parameter to xenbus_read_driver_state()
  xen/xenbus: better handle backend crash

 drivers/net/xen-netfront.c                 | 34 +++++++++---------
 drivers/pci/xen-pcifront.c                 |  8 ++---
 drivers/scsi/xen-scsifront.c               |  2 +-
 drivers/xen/xen-pciback/xenbus.c           | 10 +++---
 drivers/xen/xenbus/xenbus_client.c         | 17 +++++++--
 drivers/xen/xenbus/xenbus_probe.c          | 42 ++++++++++++++++++++--
 drivers/xen/xenbus/xenbus_probe_frontend.c |  2 +-
 include/xen/xenbus.h                       |  4 ++-
 8 files changed, 84 insertions(+), 35 deletions(-)

-- 
2.53.0

[PATCH v2 1/2] xenbus: add xenbus_device parameter to xenbus_read_driver_state()

[Juergen Gross]

In order to prepare checking the xenbus device status in
xenbus_read_driver_state(), add the pointer to struct xenbus_device
as a parameter.

Signed-off-by: Juergen Gross <jgross@suse.com>
Tested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
---
V2:
- add dev parameter description (kernel test robot)
---
 drivers/net/xen-netfront.c                 | 34 +++++++++++-----------
 drivers/pci/xen-pcifront.c                 |  8 ++---
 drivers/scsi/xen-scsifront.c               |  2 +-
 drivers/xen/xen-pciback/xenbus.c           | 10 +++----
 drivers/xen/xenbus/xenbus_client.c         |  4 ++-
 drivers/xen/xenbus/xenbus_probe.c          |  6 ++--
 drivers/xen/xenbus/xenbus_probe_frontend.c |  2 +-
 include/xen/xenbus.h                       |  3 +-
 8 files changed, 36 insertions(+), 33 deletions(-)

diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
index 0969d5c9f6b7..2c414b77dd0f 100644
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -1646,7 +1646,7 @@ static int xennet_xdp_set(struct net_device *dev, struct bpf_prog *prog,
 
 	/* avoid the race with XDP headroom adjustment */
 	wait_event(module_wq,
-		   xenbus_read_driver_state(np->xbdev->otherend) ==
+		   xenbus_read_driver_state(np->xbdev, np->xbdev->otherend) ==
 		   XenbusStateReconfigured);
 	np->netfront_xdp_enabled = true;
 
@@ -1764,9 +1764,9 @@ static struct net_device *xennet_create_dev(struct xenbus_device *dev)
 	do {
 		xenbus_switch_state(dev, XenbusStateInitialising);
 		err = wait_event_timeout(module_wq,
-				 xenbus_read_driver_state(dev->otherend) !=
+				 xenbus_read_driver_state(dev, dev->otherend) !=
 				 XenbusStateClosed &&
-				 xenbus_read_driver_state(dev->otherend) !=
+				 xenbus_read_driver_state(dev, dev->otherend) !=
 				 XenbusStateUnknown, XENNET_TIMEOUT);
 	} while (!err);
 
@@ -2627,31 +2627,31 @@ static void xennet_bus_close(struct xenbus_device *dev)
 {
 	int ret;
 
-	if (xenbus_read_driver_state(dev->otherend) == XenbusStateClosed)
+	if (xenbus_read_driver_state(dev, dev->otherend) == XenbusStateClosed)
 		return;
 	do {
 		xenbus_switch_state(dev, XenbusStateClosing);
 		ret = wait_event_timeout(module_wq,
-				   xenbus_read_driver_state(dev->otherend) ==
-				   XenbusStateClosing ||
-				   xenbus_read_driver_state(dev->otherend) ==
-				   XenbusStateClosed ||
-				   xenbus_read_driver_state(dev->otherend) ==
-				   XenbusStateUnknown,
-				   XENNET_TIMEOUT);
+				xenbus_read_driver_state(dev, dev->otherend) ==
+				XenbusStateClosing ||
+				xenbus_read_driver_state(dev, dev->otherend) ==
+				XenbusStateClosed ||
+				xenbus_read_driver_state(dev, dev->otherend) ==
+				XenbusStateUnknown,
+				XENNET_TIMEOUT);
 	} while (!ret);
 
-	if (xenbus_read_driver_state(dev->otherend) == XenbusStateClosed)
+	if (xenbus_read_driver_state(dev, dev->otherend) == XenbusStateClosed)
 		return;
 
 	do {
 		xenbus_switch_state(dev, XenbusStateClosed);
 		ret = wait_event_timeout(module_wq,
-				   xenbus_read_driver_state(dev->otherend) ==
-				   XenbusStateClosed ||
-				   xenbus_read_driver_state(dev->otherend) ==
-				   XenbusStateUnknown,
-				   XENNET_TIMEOUT);
+				xenbus_read_driver_state(dev, dev->otherend) ==
+				XenbusStateClosed ||
+				xenbus_read_driver_state(dev, dev->otherend) ==
+				XenbusStateUnknown,
+				XENNET_TIMEOUT);
 	} while (!ret);
 }
 
diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c
index 11636634ae51..cd22bf984024 100644
--- a/drivers/pci/xen-pcifront.c
+++ b/drivers/pci/xen-pcifront.c
@@ -856,7 +856,7 @@ static void pcifront_try_connect(struct pcifront_device *pdev)
 	int err;
 
 	/* Only connect once */
-	if (xenbus_read_driver_state(pdev->xdev->nodename) !=
+	if (xenbus_read_driver_state(pdev->xdev, pdev->xdev->nodename) !=
 	    XenbusStateInitialised)
 		return;
 
@@ -876,7 +876,7 @@ static int pcifront_try_disconnect(struct pcifront_device *pdev)
 	enum xenbus_state prev_state;
 
 
-	prev_state = xenbus_read_driver_state(pdev->xdev->nodename);
+	prev_state = xenbus_read_driver_state(pdev->xdev, pdev->xdev->nodename);
 
 	if (prev_state >= XenbusStateClosing)
 		goto out;
@@ -895,7 +895,7 @@ static int pcifront_try_disconnect(struct pcifront_device *pdev)
 
 static void pcifront_attach_devices(struct pcifront_device *pdev)
 {
-	if (xenbus_read_driver_state(pdev->xdev->nodename) ==
+	if (xenbus_read_driver_state(pdev->xdev, pdev->xdev->nodename) ==
 	    XenbusStateReconfiguring)
 		pcifront_connect(pdev);
 }
@@ -909,7 +909,7 @@ static int pcifront_detach_devices(struct pcifront_device *pdev)
 	struct pci_dev *pci_dev;
 	char str[64];
 
-	state = xenbus_read_driver_state(pdev->xdev->nodename);
+	state = xenbus_read_driver_state(pdev->xdev, pdev->xdev->nodename);
 	if (state == XenbusStateInitialised) {
 		dev_dbg(&pdev->xdev->dev, "Handle skipped connect.\n");
 		/* We missed Connected and need to initialize. */
diff --git a/drivers/scsi/xen-scsifront.c b/drivers/scsi/xen-scsifront.c
index 924025305753..ef74d4da5ab0 100644
--- a/drivers/scsi/xen-scsifront.c
+++ b/drivers/scsi/xen-scsifront.c
@@ -1175,7 +1175,7 @@ static void scsifront_backend_changed(struct xenbus_device *dev,
 			return;
 		}
 
-		if (xenbus_read_driver_state(dev->nodename) ==
+		if (xenbus_read_driver_state(dev, dev->nodename) ==
 		    XenbusStateInitialised)
 			scsifront_do_lun_hotplug(info, VSCSIFRONT_OP_ADD_LUN);
 
diff --git a/drivers/xen/xen-pciback/xenbus.c b/drivers/xen/xen-pciback/xenbus.c
index b11e401f1b1e..4bd1c7a8957e 100644
--- a/drivers/xen/xen-pciback/xenbus.c
+++ b/drivers/xen/xen-pciback/xenbus.c
@@ -149,12 +149,12 @@ static int xen_pcibk_attach(struct xen_pcibk_device *pdev)
 
 	mutex_lock(&pdev->dev_lock);
 	/* Make sure we only do this setup once */
-	if (xenbus_read_driver_state(pdev->xdev->nodename) !=
+	if (xenbus_read_driver_state(pdev->xdev, pdev->xdev->nodename) !=
 	    XenbusStateInitialised)
 		goto out;
 
 	/* Wait for frontend to state that it has published the configuration */
-	if (xenbus_read_driver_state(pdev->xdev->otherend) !=
+	if (xenbus_read_driver_state(pdev->xdev, pdev->xdev->otherend) !=
 	    XenbusStateInitialised)
 		goto out;
 
@@ -374,7 +374,7 @@ static int xen_pcibk_reconfigure(struct xen_pcibk_device *pdev,
 	dev_dbg(&pdev->xdev->dev, "Reconfiguring device ...\n");
 
 	mutex_lock(&pdev->dev_lock);
-	if (xenbus_read_driver_state(pdev->xdev->nodename) != state)
+	if (xenbus_read_driver_state(pdev->xdev, pdev->xdev->nodename) != state)
 		goto out;
 
 	err = xenbus_scanf(XBT_NIL, pdev->xdev->nodename, "num_devs", "%d",
@@ -572,7 +572,7 @@ static int xen_pcibk_setup_backend(struct xen_pcibk_device *pdev)
 	/* It's possible we could get the call to setup twice, so make sure
 	 * we're not already connected.
 	 */
-	if (xenbus_read_driver_state(pdev->xdev->nodename) !=
+	if (xenbus_read_driver_state(pdev->xdev, pdev->xdev->nodename) !=
 	    XenbusStateInitWait)
 		goto out;
 
@@ -662,7 +662,7 @@ static void xen_pcibk_be_watch(struct xenbus_watch *watch,
 	struct xen_pcibk_device *pdev =
 	    container_of(watch, struct xen_pcibk_device, be_watch);
 
-	switch (xenbus_read_driver_state(pdev->xdev->nodename)) {
+	switch (xenbus_read_driver_state(pdev->xdev, pdev->xdev->nodename)) {
 	case XenbusStateInitWait:
 		xen_pcibk_setup_backend(pdev);
 		break;
diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c
index 2dc874fb5506..e502435145ae 100644
--- a/drivers/xen/xenbus/xenbus_client.c
+++ b/drivers/xen/xenbus/xenbus_client.c
@@ -931,12 +931,14 @@ static int xenbus_unmap_ring_hvm(struct xenbus_device *dev, void *vaddr)
 
 /**
  * xenbus_read_driver_state - read state from a store path
+ * @dev: xenbus device pointer
  * @path: path for driver
  *
  * Returns: the state of the driver rooted at the given store path, or
  * XenbusStateUnknown if no state can be read.
  */
-enum xenbus_state xenbus_read_driver_state(const char *path)
+enum xenbus_state xenbus_read_driver_state(const struct xenbus_device *dev,
+					   const char *path)
 {
 	enum xenbus_state result;
 	int err = xenbus_gather(XBT_NIL, path, "state", "%d", &result, NULL);
diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c
index 9f9011cd7447..2eed06ba5d38 100644
--- a/drivers/xen/xenbus/xenbus_probe.c
+++ b/drivers/xen/xenbus/xenbus_probe.c
@@ -191,7 +191,7 @@ void xenbus_otherend_changed(struct xenbus_watch *watch,
 		return;
 	}
 
-	state = xenbus_read_driver_state(dev->otherend);
+	state = xenbus_read_driver_state(dev, dev->otherend);
 
 	dev_dbg(&dev->dev, "state is %d, (%s), %s, %s\n",
 		state, xenbus_strstate(state), dev->otherend_watch.node, path);
@@ -364,7 +364,7 @@ void xenbus_dev_remove(struct device *_dev)
 	 * closed.
 	 */
 	if (!drv->allow_rebind ||
-	    xenbus_read_driver_state(dev->nodename) == XenbusStateClosing)
+	    xenbus_read_driver_state(dev, dev->nodename) == XenbusStateClosing)
 		xenbus_switch_state(dev, XenbusStateClosed);
 }
 EXPORT_SYMBOL_GPL(xenbus_dev_remove);
@@ -514,7 +514,7 @@ int xenbus_probe_node(struct xen_bus_type *bus,
 	size_t stringlen;
 	char *tmpstring;
 
-	enum xenbus_state state = xenbus_read_driver_state(nodename);
+	enum xenbus_state state = xenbus_read_driver_state(NULL, nodename);
 
 	if (state != XenbusStateInitialising) {
 		/* Device is not new, so ignore it.  This can happen if a
diff --git a/drivers/xen/xenbus/xenbus_probe_frontend.c b/drivers/xen/xenbus/xenbus_probe_frontend.c
index f04707d1f667..ca04609730df 100644
--- a/drivers/xen/xenbus/xenbus_probe_frontend.c
+++ b/drivers/xen/xenbus/xenbus_probe_frontend.c
@@ -253,7 +253,7 @@ static int print_device_status(struct device *dev, void *data)
 	} else if (xendev->state < XenbusStateConnected) {
 		enum xenbus_state rstate = XenbusStateUnknown;
 		if (xendev->otherend)
-			rstate = xenbus_read_driver_state(xendev->otherend);
+			rstate = xenbus_read_driver_state(xendev, xendev->otherend);
 		pr_warn("Timeout connecting to device: %s (local state %d, remote state %d)\n",
 			xendev->nodename, xendev->state, rstate);
 	}
diff --git a/include/xen/xenbus.h b/include/xen/xenbus.h
index c94caf852aea..15319da65b7f 100644
--- a/include/xen/xenbus.h
+++ b/include/xen/xenbus.h
@@ -228,7 +228,8 @@ int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr);
 int xenbus_alloc_evtchn(struct xenbus_device *dev, evtchn_port_t *port);
 int xenbus_free_evtchn(struct xenbus_device *dev, evtchn_port_t port);
 
-enum xenbus_state xenbus_read_driver_state(const char *path);
+enum xenbus_state xenbus_read_driver_state(const struct xenbus_device *dev,
+					   const char *path);
 
 __printf(3, 4)
 void xenbus_dev_error(struct xenbus_device *dev, int err, const char *fmt, ...);
-- 
2.53.0

Re: [PATCH v2 1/2] xenbus: add xenbus_device parameter to xenbus_read_driver_state()

[Bjorn Helgaas]

On Wed, Feb 18, 2026 at 10:52:04AM +0100, Juergen Gross wrote:
> In order to prepare checking the xenbus device status in
> xenbus_read_driver_state(), add the pointer to struct xenbus_device
> as a parameter.
> 
> Signed-off-by: Juergen Gross <jgross@suse.com>
> Tested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
> Signed-off-by: Juergen Gross <jgross@suse.com>
> ---
> V2:
> - add dev parameter description (kernel test robot)
> ---
>  drivers/net/xen-netfront.c                 | 34 +++++++++++-----------
>  drivers/pci/xen-pcifront.c                 |  8 ++---

Acked-by: Bjorn Helgaas <bhelgaas@google.com>	# drivers/pci/xen-pcifront.c

>  drivers/scsi/xen-scsifront.c               |  2 +-
>  drivers/xen/xen-pciback/xenbus.c           | 10 +++----
>  drivers/xen/xenbus/xenbus_client.c         |  4 ++-
>  drivers/xen/xenbus/xenbus_probe.c          |  6 ++--
>  drivers/xen/xenbus/xenbus_probe_frontend.c |  2 +-
>  include/xen/xenbus.h                       |  3 +-
>  8 files changed, 36 insertions(+), 33 deletions(-)
> 
> diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
> index 0969d5c9f6b7..2c414b77dd0f 100644
> --- a/drivers/net/xen-netfront.c
> +++ b/drivers/net/xen-netfront.c
> @@ -1646,7 +1646,7 @@ static int xennet_xdp_set(struct net_device *dev, struct bpf_prog *prog,
>  
>  	/* avoid the race with XDP headroom adjustment */
>  	wait_event(module_wq,
> -		   xenbus_read_driver_state(np->xbdev->otherend) ==
> +		   xenbus_read_driver_state(np->xbdev, np->xbdev->otherend) ==
>  		   XenbusStateReconfigured);
>  	np->netfront_xdp_enabled = true;
>  
> @@ -1764,9 +1764,9 @@ static struct net_device *xennet_create_dev(struct xenbus_device *dev)
>  	do {
>  		xenbus_switch_state(dev, XenbusStateInitialising);
>  		err = wait_event_timeout(module_wq,
> -				 xenbus_read_driver_state(dev->otherend) !=
> +				 xenbus_read_driver_state(dev, dev->otherend) !=
>  				 XenbusStateClosed &&
> -				 xenbus_read_driver_state(dev->otherend) !=
> +				 xenbus_read_driver_state(dev, dev->otherend) !=
>  				 XenbusStateUnknown, XENNET_TIMEOUT);
>  	} while (!err);
>  
> @@ -2627,31 +2627,31 @@ static void xennet_bus_close(struct xenbus_device *dev)
>  {
>  	int ret;
>  
> -	if (xenbus_read_driver_state(dev->otherend) == XenbusStateClosed)
> +	if (xenbus_read_driver_state(dev, dev->otherend) == XenbusStateClosed)
>  		return;
>  	do {
>  		xenbus_switch_state(dev, XenbusStateClosing);
>  		ret = wait_event_timeout(module_wq,
> -				   xenbus_read_driver_state(dev->otherend) ==
> -				   XenbusStateClosing ||
> -				   xenbus_read_driver_state(dev->otherend) ==
> -				   XenbusStateClosed ||
> -				   xenbus_read_driver_state(dev->otherend) ==
> -				   XenbusStateUnknown,
> -				   XENNET_TIMEOUT);
> +				xenbus_read_driver_state(dev, dev->otherend) ==
> +				XenbusStateClosing ||
> +				xenbus_read_driver_state(dev, dev->otherend) ==
> +				XenbusStateClosed ||
> +				xenbus_read_driver_state(dev, dev->otherend) ==
> +				XenbusStateUnknown,
> +				XENNET_TIMEOUT);
>  	} while (!ret);
>  
> -	if (xenbus_read_driver_state(dev->otherend) == XenbusStateClosed)
> +	if (xenbus_read_driver_state(dev, dev->otherend) == XenbusStateClosed)
>  		return;
>  
>  	do {
>  		xenbus_switch_state(dev, XenbusStateClosed);
>  		ret = wait_event_timeout(module_wq,
> -				   xenbus_read_driver_state(dev->otherend) ==
> -				   XenbusStateClosed ||
> -				   xenbus_read_driver_state(dev->otherend) ==
> -				   XenbusStateUnknown,
> -				   XENNET_TIMEOUT);
> +				xenbus_read_driver_state(dev, dev->otherend) ==
> +				XenbusStateClosed ||
> +				xenbus_read_driver_state(dev, dev->otherend) ==
> +				XenbusStateUnknown,
> +				XENNET_TIMEOUT);
>  	} while (!ret);
>  }
>  
> diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c
> index 11636634ae51..cd22bf984024 100644
> --- a/drivers/pci/xen-pcifront.c
> +++ b/drivers/pci/xen-pcifront.c
> @@ -856,7 +856,7 @@ static void pcifront_try_connect(struct pcifront_device *pdev)
>  	int err;
>  
>  	/* Only connect once */
> -	if (xenbus_read_driver_state(pdev->xdev->nodename) !=
> +	if (xenbus_read_driver_state(pdev->xdev, pdev->xdev->nodename) !=
>  	    XenbusStateInitialised)
>  		return;
>  
> @@ -876,7 +876,7 @@ static int pcifront_try_disconnect(struct pcifront_device *pdev)
>  	enum xenbus_state prev_state;
>  
>  
> -	prev_state = xenbus_read_driver_state(pdev->xdev->nodename);
> +	prev_state = xenbus_read_driver_state(pdev->xdev, pdev->xdev->nodename);
>  
>  	if (prev_state >= XenbusStateClosing)
>  		goto out;
> @@ -895,7 +895,7 @@ static int pcifront_try_disconnect(struct pcifront_device *pdev)
>  
>  static void pcifront_attach_devices(struct pcifront_device *pdev)
>  {
> -	if (xenbus_read_driver_state(pdev->xdev->nodename) ==
> +	if (xenbus_read_driver_state(pdev->xdev, pdev->xdev->nodename) ==
>  	    XenbusStateReconfiguring)
>  		pcifront_connect(pdev);
>  }
> @@ -909,7 +909,7 @@ static int pcifront_detach_devices(struct pcifront_device *pdev)
>  	struct pci_dev *pci_dev;
>  	char str[64];
>  
> -	state = xenbus_read_driver_state(pdev->xdev->nodename);
> +	state = xenbus_read_driver_state(pdev->xdev, pdev->xdev->nodename);
>  	if (state == XenbusStateInitialised) {
>  		dev_dbg(&pdev->xdev->dev, "Handle skipped connect.\n");
>  		/* We missed Connected and need to initialize. */
> diff --git a/drivers/scsi/xen-scsifront.c b/drivers/scsi/xen-scsifront.c
> index 924025305753..ef74d4da5ab0 100644
> --- a/drivers/scsi/xen-scsifront.c
> +++ b/drivers/scsi/xen-scsifront.c
> @@ -1175,7 +1175,7 @@ static void scsifront_backend_changed(struct xenbus_device *dev,
>  			return;
>  		}
>  
> -		if (xenbus_read_driver_state(dev->nodename) ==
> +		if (xenbus_read_driver_state(dev, dev->nodename) ==
>  		    XenbusStateInitialised)
>  			scsifront_do_lun_hotplug(info, VSCSIFRONT_OP_ADD_LUN);
>  
> diff --git a/drivers/xen/xen-pciback/xenbus.c b/drivers/xen/xen-pciback/xenbus.c
> index b11e401f1b1e..4bd1c7a8957e 100644
> --- a/drivers/xen/xen-pciback/xenbus.c
> +++ b/drivers/xen/xen-pciback/xenbus.c
> @@ -149,12 +149,12 @@ static int xen_pcibk_attach(struct xen_pcibk_device *pdev)
>  
>  	mutex_lock(&pdev->dev_lock);
>  	/* Make sure we only do this setup once */
> -	if (xenbus_read_driver_state(pdev->xdev->nodename) !=
> +	if (xenbus_read_driver_state(pdev->xdev, pdev->xdev->nodename) !=
>  	    XenbusStateInitialised)
>  		goto out;
>  
>  	/* Wait for frontend to state that it has published the configuration */
> -	if (xenbus_read_driver_state(pdev->xdev->otherend) !=
> +	if (xenbus_read_driver_state(pdev->xdev, pdev->xdev->otherend) !=
>  	    XenbusStateInitialised)
>  		goto out;
>  
> @@ -374,7 +374,7 @@ static int xen_pcibk_reconfigure(struct xen_pcibk_device *pdev,
>  	dev_dbg(&pdev->xdev->dev, "Reconfiguring device ...\n");
>  
>  	mutex_lock(&pdev->dev_lock);
> -	if (xenbus_read_driver_state(pdev->xdev->nodename) != state)
> +	if (xenbus_read_driver_state(pdev->xdev, pdev->xdev->nodename) != state)
>  		goto out;
>  
>  	err = xenbus_scanf(XBT_NIL, pdev->xdev->nodename, "num_devs", "%d",
> @@ -572,7 +572,7 @@ static int xen_pcibk_setup_backend(struct xen_pcibk_device *pdev)
>  	/* It's possible we could get the call to setup twice, so make sure
>  	 * we're not already connected.
>  	 */
> -	if (xenbus_read_driver_state(pdev->xdev->nodename) !=
> +	if (xenbus_read_driver_state(pdev->xdev, pdev->xdev->nodename) !=
>  	    XenbusStateInitWait)
>  		goto out;
>  
> @@ -662,7 +662,7 @@ static void xen_pcibk_be_watch(struct xenbus_watch *watch,
>  	struct xen_pcibk_device *pdev =
>  	    container_of(watch, struct xen_pcibk_device, be_watch);
>  
> -	switch (xenbus_read_driver_state(pdev->xdev->nodename)) {
> +	switch (xenbus_read_driver_state(pdev->xdev, pdev->xdev->nodename)) {
>  	case XenbusStateInitWait:
>  		xen_pcibk_setup_backend(pdev);
>  		break;
> diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c
> index 2dc874fb5506..e502435145ae 100644
> --- a/drivers/xen/xenbus/xenbus_client.c
> +++ b/drivers/xen/xenbus/xenbus_client.c
> @@ -931,12 +931,14 @@ static int xenbus_unmap_ring_hvm(struct xenbus_device *dev, void *vaddr)
>  
>  /**
>   * xenbus_read_driver_state - read state from a store path
> + * @dev: xenbus device pointer
>   * @path: path for driver
>   *
>   * Returns: the state of the driver rooted at the given store path, or
>   * XenbusStateUnknown if no state can be read.
>   */
> -enum xenbus_state xenbus_read_driver_state(const char *path)
> +enum xenbus_state xenbus_read_driver_state(const struct xenbus_device *dev,
> +					   const char *path)
>  {
>  	enum xenbus_state result;
>  	int err = xenbus_gather(XBT_NIL, path, "state", "%d", &result, NULL);
> diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c
> index 9f9011cd7447..2eed06ba5d38 100644
> --- a/drivers/xen/xenbus/xenbus_probe.c
> +++ b/drivers/xen/xenbus/xenbus_probe.c
> @@ -191,7 +191,7 @@ void xenbus_otherend_changed(struct xenbus_watch *watch,
>  		return;
>  	}
>  
> -	state = xenbus_read_driver_state(dev->otherend);
> +	state = xenbus_read_driver_state(dev, dev->otherend);
>  
>  	dev_dbg(&dev->dev, "state is %d, (%s), %s, %s\n",
>  		state, xenbus_strstate(state), dev->otherend_watch.node, path);
> @@ -364,7 +364,7 @@ void xenbus_dev_remove(struct device *_dev)
>  	 * closed.
>  	 */
>  	if (!drv->allow_rebind ||
> -	    xenbus_read_driver_state(dev->nodename) == XenbusStateClosing)
> +	    xenbus_read_driver_state(dev, dev->nodename) == XenbusStateClosing)
>  		xenbus_switch_state(dev, XenbusStateClosed);
>  }
>  EXPORT_SYMBOL_GPL(xenbus_dev_remove);
> @@ -514,7 +514,7 @@ int xenbus_probe_node(struct xen_bus_type *bus,
>  	size_t stringlen;
>  	char *tmpstring;
>  
> -	enum xenbus_state state = xenbus_read_driver_state(nodename);
> +	enum xenbus_state state = xenbus_read_driver_state(NULL, nodename);
>  
>  	if (state != XenbusStateInitialising) {
>  		/* Device is not new, so ignore it.  This can happen if a
> diff --git a/drivers/xen/xenbus/xenbus_probe_frontend.c b/drivers/xen/xenbus/xenbus_probe_frontend.c
> index f04707d1f667..ca04609730df 100644
> --- a/drivers/xen/xenbus/xenbus_probe_frontend.c
> +++ b/drivers/xen/xenbus/xenbus_probe_frontend.c
> @@ -253,7 +253,7 @@ static int print_device_status(struct device *dev, void *data)
>  	} else if (xendev->state < XenbusStateConnected) {
>  		enum xenbus_state rstate = XenbusStateUnknown;
>  		if (xendev->otherend)
> -			rstate = xenbus_read_driver_state(xendev->otherend);
> +			rstate = xenbus_read_driver_state(xendev, xendev->otherend);
>  		pr_warn("Timeout connecting to device: %s (local state %d, remote state %d)\n",
>  			xendev->nodename, xendev->state, rstate);
>  	}
> diff --git a/include/xen/xenbus.h b/include/xen/xenbus.h
> index c94caf852aea..15319da65b7f 100644
> --- a/include/xen/xenbus.h
> +++ b/include/xen/xenbus.h
> @@ -228,7 +228,8 @@ int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr);
>  int xenbus_alloc_evtchn(struct xenbus_device *dev, evtchn_port_t *port);
>  int xenbus_free_evtchn(struct xenbus_device *dev, evtchn_port_t port);
>  
> -enum xenbus_state xenbus_read_driver_state(const char *path);
> +enum xenbus_state xenbus_read_driver_state(const struct xenbus_device *dev,
> +					   const char *path);
>  
>  __printf(3, 4)
>  void xenbus_dev_error(struct xenbus_device *dev, int err, const char *fmt, ...);
> -- 
> 2.53.0
> 

Re: [PATCH v2 1/2] xenbus: add xenbus_device parameter to xenbus_read_driver_state()

[Jakub Kicinski]

On Wed, 18 Feb 2026 10:52:04 +0100 Juergen Gross wrote:
>  drivers/net/xen-netfront.c                 | 34 +++++++++++-----------

Acked-by: Jakub Kicinski <kuba@kernel.org>
-- 
pw-bot: nap

Re: [PATCH v2 1/2] xenbus: add xenbus_device parameter to xenbus_read_driver_state()

[Martin K. Petersen]

Juergen,

> In order to prepare checking the xenbus device status in
> xenbus_read_driver_state(), add the pointer to struct xenbus_device
> as a parameter.

Acked-by: Martin K. Petersen <martin.petersen@oracle.com> # SCSI

-- 
Martin K. Petersen