[driver-core,v9,1/9] driver core: Establish order of operations for device_add and device_del via bitflag

Commit Message

Alexander Duyck Dec. 13, 2018, 12:44 a.m. UTC

Add an additional bit flag to the device struct named "dead".

This additional flag provides a guarantee that when a device_del is
executed on a given interface an async worker will not attempt to attach
the driver following the earlier device_del call. Previously this
guarantee was not present and could result in the device_del call
attempting to remove a driver from an interface only to have the async
worker attempt to probe the driver later when it finally completes the
asynchronous probe call.

One additional change added was that I pulled the check for dev->driver
out of the __device_attach_driver call and instead placed it in the
__device_attach_async_helper call. This was motivated by the fact that the
only other caller of this, __device_attach, had already taken the
device_lock() and checked for dev->driver. Instead of testing for this
twice in this path it makes more sense to just consolidate the dev->dead
and dev->driver checks together into one set of checks.

Reviewed-by: Dan Williams <[e-mail]>
Signed-off-by: Alexander Duyck <[e-mail]>
---
 drivers/base/core.c    |   11 +++++++++++
 drivers/base/dd.c      |   22 +++++++++++-----------
 include/linux/device.h |    5 +++++
 3 files changed, 27 insertions(+), 11 deletions(-)

Comments

Rafael J. Wysocki Dec. 19, 2018, 2:27 p.m. UTC | #1

On Thu, Dec 13, 2018 at 1:45 AM Alexander Duyck
<[e-mail]> wrote:
>
> Add an additional bit flag to the device struct named "dead".
>
> This additional flag provides a guarantee that when a device_del is
> executed on a given interface an async worker will not attempt to attach
> the driver following the earlier device_del call. Previously this
> guarantee was not present and could result in the device_del call
> attempting to remove a driver from an interface only to have the async
> worker attempt to probe the driver later when it finally completes the
> asynchronous probe call.
>
> One additional change added was that I pulled the check for dev->driver
> out of the __device_attach_driver call and instead placed it in the
> __device_attach_async_helper call. This was motivated by the fact that the
> only other caller of this, __device_attach, had already taken the
> device_lock() and checked for dev->driver. Instead of testing for this
> twice in this path it makes more sense to just consolidate the dev->dead
> and dev->driver checks together into one set of checks.
>
> Reviewed-by: Dan Williams <[e-mail]>
> Signed-off-by: Alexander Duyck <[e-mail]>

Reviewed-by: Rafael J. Wysocki <[e-mail]>

> ---
>  drivers/base/core.c    |   11 +++++++++++
>  drivers/base/dd.c      |   22 +++++++++++-----------
>  include/linux/device.h |    5 +++++
>  3 files changed, 27 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/base/core.c b/drivers/base/core.c
> index 0073b09bb99f..950e25495726 100644
> --- a/drivers/base/core.c
> +++ b/drivers/base/core.c
> @@ -2080,6 +2080,17 @@ void device_del(struct device *dev)
>         struct kobject *glue_dir = NULL;
>         struct class_interface *class_intf;
>
> +       /*
> +        * Hold the device lock and set the "dead" flag to guarantee that
> +        * the update behavior is consistent with the other bitfields near
> +        * it and that we cannot have an asynchronous probe routine trying
> +        * to run while we are tearing out the bus/class/sysfs from
> +        * underneath the device.
> +        */
> +       device_lock(dev);
> +       dev->dead = true;
> +       device_unlock(dev);
> +
>         /* Notify clients of device removal.  This call must come
>          * before dpm_sysfs_remove().
>          */
> diff --git a/drivers/base/dd.c b/drivers/base/dd.c
> index 88713f182086..74c194ac99df 100644
> --- a/drivers/base/dd.c
> +++ b/drivers/base/dd.c
> @@ -731,15 +731,6 @@ static int __device_attach_driver(struct device_driver *drv, void *_data)
>         bool async_allowed;
>         int ret;
>
> -       /*
> -        * Check if device has already been claimed. This may
> -        * happen with driver loading, device discovery/registration,
> -        * and deferred probe processing happens all at once with
> -        * multiple threads.
> -        */
> -       if (dev->driver)
> -               return -EBUSY;
> -
>         ret = driver_match_device(drv, dev);
>         if (ret == 0) {
>                 /* no match */
> @@ -774,6 +765,15 @@ static void __device_attach_async_helper(void *_dev, async_cookie_t cookie)
>
>         device_lock(dev);
>
> +       /*
> +        * Check if device has already been removed or claimed. This may
> +        * happen with driver loading, device discovery/registration,
> +        * and deferred probe processing happens all at once with
> +        * multiple threads.
> +        */
> +       if (dev->dead || dev->driver)
> +               goto out_unlock;
> +
>         if (dev->parent)
>                 pm_runtime_get_sync(dev->parent);
>
> @@ -784,7 +784,7 @@ static void __device_attach_async_helper(void *_dev, async_cookie_t cookie)
>
>         if (dev->parent)
>                 pm_runtime_put(dev->parent);
> -
> +out_unlock:
>         device_unlock(dev);
>
>         put_device(dev);
> @@ -897,7 +897,7 @@ static int __driver_attach(struct device *dev, void *data)
>         if (dev->parent && dev->bus->need_parent_lock)
>                 device_lock(dev->parent);
>         device_lock(dev);
> -       if (!dev->driver)
> +       if (!dev->dead && !dev->driver)
>                 driver_probe_device(drv, dev);
>         device_unlock(dev);
>         if (dev->parent && dev->bus->need_parent_lock)
> diff --git a/include/linux/device.h b/include/linux/device.h
> index 1b25c7a43f4c..f73dad81e811 100644
> --- a/include/linux/device.h
> +++ b/include/linux/device.h
> @@ -957,6 +957,10 @@ struct dev_links_info {
>   *              device.
>   * @dma_coherent: this particular device is dma coherent, even if the
>   *             architecture supports non-coherent devices.
> + * @dead:      This device is currently either in the process of or has
> + *             been removed from the system. Any asynchronous events
> + *             scheduled for this device should exit without taking any
> + *             action.
>   *
>   * At the lowest level, every device in a Linux system is represented by an
>   * instance of struct device. The device structure contains the information
> @@ -1051,6 +1055,7 @@ struct device {
>      defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
>         bool                    dma_coherent:1;
>  #endif
> +       bool                    dead:1;
>  };
>
>  static inline struct device *kobj_to_dev(struct kobject *kobj)
>

Greg Kroah-Hartman Dec. 20, 2018, 3:28 p.m. UTC | #2

On Wed, Dec 19, 2018 at 03:27:48PM +0100, Rafael J. Wysocki wrote:
> On Thu, Dec 13, 2018 at 1:45 AM Alexander Duyck
> <[e-mail]> wrote:
> >
> > Add an additional bit flag to the device struct named "dead".
> >
> > This additional flag provides a guarantee that when a device_del is
> > executed on a given interface an async worker will not attempt to attach
> > the driver following the earlier device_del call. Previously this
> > guarantee was not present and could result in the device_del call
> > attempting to remove a driver from an interface only to have the async
> > worker attempt to probe the driver later when it finally completes the
> > asynchronous probe call.
> >
> > One additional change added was that I pulled the check for dev->driver
> > out of the __device_attach_driver call and instead placed it in the
> > __device_attach_async_helper call. This was motivated by the fact that the
> > only other caller of this, __device_attach, had already taken the
> > device_lock() and checked for dev->driver. Instead of testing for this
> > twice in this path it makes more sense to just consolidate the dev->dead
> > and dev->driver checks together into one set of checks.
> >
> > Reviewed-by: Dan Williams <[e-mail]>
> > Signed-off-by: Alexander Duyck <[e-mail]>
> 
> Reviewed-by: Rafael J. Wysocki <[e-mail]>

It's too late for 4.21-rc1 as my tree should be closed by now.

So I'll hold on to these in my queue until 4.21-rc1 is out and then
queue them up and see what breaks in linux-next :)

thanks,

greg k-h

Alexander Duyck Jan. 10, 2019, 5:37 p.m. UTC | #3

On Thu, 2018-12-20 at 16:28 +0100, Greg Kroah-Hartman wrote:
> On Wed, Dec 19, 2018 at 03:27:48PM +0100, Rafael J. Wysocki wrote:
> > On Thu, Dec 13, 2018 at 1:45 AM Alexander Duyck
> > <[e-mail]> wrote:
> > > 
> > > Add an additional bit flag to the device struct named "dead".
> > > 
> > > This additional flag provides a guarantee that when a device_del is
> > > executed on a given interface an async worker will not attempt to attach
> > > the driver following the earlier device_del call. Previously this
> > > guarantee was not present and could result in the device_del call
> > > attempting to remove a driver from an interface only to have the async
> > > worker attempt to probe the driver later when it finally completes the
> > > asynchronous probe call.
> > > 
> > > One additional change added was that I pulled the check for dev->driver
> > > out of the __device_attach_driver call and instead placed it in the
> > > __device_attach_async_helper call. This was motivated by the fact that the
> > > only other caller of this, __device_attach, had already taken the
> > > device_lock() and checked for dev->driver. Instead of testing for this
> > > twice in this path it makes more sense to just consolidate the dev->dead
> > > and dev->driver checks together into one set of checks.
> > > 
> > > Reviewed-by: Dan Williams <[e-mail]>
> > > Signed-off-by: Alexander Duyck <[e-mail]>
> > 
> > Reviewed-by: Rafael J. Wysocki <[e-mail]>
> 
> It's too late for 4.21-rc1 as my tree should be closed by now.
> 
> So I'll hold on to these in my queue until 4.21-rc1 is out and then
> queue them up and see what breaks in linux-next :)
> 
> thanks,
> 
> greg k-h

I just wanted to check on on this patch set in terms of workflow. Since
it looks like we now have 5.0-rc1 out I was wondering what the ETA for
this patch set being pulled was, or if I need to resubmit the set.

Thanks.

- Alex

Greg Kroah-Hartman Jan. 18, 2019, 3:50 p.m. UTC | #4

On Thu, Jan 10, 2019 at 09:37:32AM -0800, Alexander Duyck wrote:
> On Thu, 2018-12-20 at 16:28 +0100, Greg Kroah-Hartman wrote:
> > On Wed, Dec 19, 2018 at 03:27:48PM +0100, Rafael J. Wysocki wrote:
> > > On Thu, Dec 13, 2018 at 1:45 AM Alexander Duyck
> > > <[e-mail]> wrote:
> > > > 
> > > > Add an additional bit flag to the device struct named "dead".
> > > > 
> > > > This additional flag provides a guarantee that when a device_del is
> > > > executed on a given interface an async worker will not attempt to attach
> > > > the driver following the earlier device_del call. Previously this
> > > > guarantee was not present and could result in the device_del call
> > > > attempting to remove a driver from an interface only to have the async
> > > > worker attempt to probe the driver later when it finally completes the
> > > > asynchronous probe call.
> > > > 
> > > > One additional change added was that I pulled the check for dev->driver
> > > > out of the __device_attach_driver call and instead placed it in the
> > > > __device_attach_async_helper call. This was motivated by the fact that the
> > > > only other caller of this, __device_attach, had already taken the
> > > > device_lock() and checked for dev->driver. Instead of testing for this
> > > > twice in this path it makes more sense to just consolidate the dev->dead
> > > > and dev->driver checks together into one set of checks.
> > > > 
> > > > Reviewed-by: Dan Williams <[e-mail]>
> > > > Signed-off-by: Alexander Duyck <[e-mail]>
> > > 
> > > Reviewed-by: Rafael J. Wysocki <[e-mail]>
> > 
> > It's too late for 4.21-rc1 as my tree should be closed by now.
> > 
> > So I'll hold on to these in my queue until 4.21-rc1 is out and then
> > queue them up and see what breaks in linux-next :)
> > 
> > thanks,
> > 
> > greg k-h
> 
> I just wanted to check on on this patch set in terms of workflow. Since
> it looks like we now have 5.0-rc1 out I was wondering what the ETA for
> this patch set being pulled was, or if I need to resubmit the set.

I'm reviewing it now, no need to resend...

thanks,

greg k-h

Greg Kroah-Hartman Jan. 18, 2019, 3:54 p.m. UTC | #5

On Wed, Dec 12, 2018 at 04:44:58PM -0800, Alexander Duyck wrote:
> Add an additional bit flag to the device struct named "dead".
> 
> This additional flag provides a guarantee that when a device_del is
> executed on a given interface an async worker will not attempt to attach
> the driver following the earlier device_del call. Previously this
> guarantee was not present and could result in the device_del call
> attempting to remove a driver from an interface only to have the async
> worker attempt to probe the driver later when it finally completes the
> asynchronous probe call.
> 
> One additional change added was that I pulled the check for dev->driver
> out of the __device_attach_driver call and instead placed it in the
> __device_attach_async_helper call. This was motivated by the fact that the
> only other caller of this, __device_attach, had already taken the
> device_lock() and checked for dev->driver. Instead of testing for this
> twice in this path it makes more sense to just consolidate the dev->dead
> and dev->driver checks together into one set of checks.
> 
> Reviewed-by: Dan Williams <[e-mail]>
> Signed-off-by: Alexander Duyck <[e-mail]>
> Reviewed-by: Rafael J. Wysocki <[e-mail]>
> ---
>  drivers/base/core.c    |   11 +++++++++++
>  drivers/base/dd.c      |   22 +++++++++++-----------
>  include/linux/device.h |    5 +++++
>  3 files changed, 27 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/base/core.c b/drivers/base/core.c
> index 0073b09bb99f..950e25495726 100644
> --- a/drivers/base/core.c
> +++ b/drivers/base/core.c
> @@ -2080,6 +2080,17 @@ void device_del(struct device *dev)
>  	struct kobject *glue_dir = NULL;
>  	struct class_interface *class_intf;
>  
> +	/*
> +	 * Hold the device lock and set the "dead" flag to guarantee that
> +	 * the update behavior is consistent with the other bitfields near
> +	 * it and that we cannot have an asynchronous probe routine trying
> +	 * to run while we are tearing out the bus/class/sysfs from
> +	 * underneath the device.
> +	 */
> +	device_lock(dev);
> +	dev->dead = true;
> +	device_unlock(dev);
> +
>  	/* Notify clients of device removal.  This call must come
>  	 * before dpm_sysfs_remove().
>  	 */
> diff --git a/drivers/base/dd.c b/drivers/base/dd.c
> index 88713f182086..74c194ac99df 100644
> --- a/drivers/base/dd.c
> +++ b/drivers/base/dd.c
> @@ -731,15 +731,6 @@ static int __device_attach_driver(struct device_driver *drv, void *_data)
>  	bool async_allowed;
>  	int ret;
>  
> -	/*
> -	 * Check if device has already been claimed. This may
> -	 * happen with driver loading, device discovery/registration,
> -	 * and deferred probe processing happens all at once with
> -	 * multiple threads.
> -	 */
> -	if (dev->driver)
> -		return -EBUSY;
> -
>  	ret = driver_match_device(drv, dev);
>  	if (ret == 0) {
>  		/* no match */
> @@ -774,6 +765,15 @@ static void __device_attach_async_helper(void *_dev, async_cookie_t cookie)
>  
>  	device_lock(dev);
>  
> +	/*
> +	 * Check if device has already been removed or claimed. This may
> +	 * happen with driver loading, device discovery/registration,
> +	 * and deferred probe processing happens all at once with
> +	 * multiple threads.
> +	 */
> +	if (dev->dead || dev->driver)
> +		goto out_unlock;
> +
>  	if (dev->parent)
>  		pm_runtime_get_sync(dev->parent);
>  
> @@ -784,7 +784,7 @@ static void __device_attach_async_helper(void *_dev, async_cookie_t cookie)
>  
>  	if (dev->parent)
>  		pm_runtime_put(dev->parent);
> -
> +out_unlock:
>  	device_unlock(dev);
>  
>  	put_device(dev);
> @@ -897,7 +897,7 @@ static int __driver_attach(struct device *dev, void *data)
>  	if (dev->parent && dev->bus->need_parent_lock)
>  		device_lock(dev->parent);
>  	device_lock(dev);
> -	if (!dev->driver)
> +	if (!dev->dead && !dev->driver)
>  		driver_probe_device(drv, dev);
>  	device_unlock(dev);
>  	if (dev->parent && dev->bus->need_parent_lock)
> diff --git a/include/linux/device.h b/include/linux/device.h
> index 1b25c7a43f4c..f73dad81e811 100644
> --- a/include/linux/device.h
> +++ b/include/linux/device.h
> @@ -957,6 +957,10 @@ struct dev_links_info {
>   *              device.
>   * @dma_coherent: this particular device is dma coherent, even if the
>   *		architecture supports non-coherent devices.
> + * @dead:	This device is currently either in the process of or has
> + *		been removed from the system. Any asynchronous events
> + *		scheduled for this device should exit without taking any
> + *		action.
>   *
>   * At the lowest level, every device in a Linux system is represented by an
>   * instance of struct device. The device structure contains the information
> @@ -1051,6 +1055,7 @@ struct device {
>      defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
>  	bool			dma_coherent:1;
>  #endif
> +	bool			dead:1;

This really should live in the struct device_private structure, as
nothing outside of the driver core should care about this, or touch it.

A number of other bitfields should also move there as well, your's isn't
the only one that I missed this for.

So can you make that quick change, and rebase (you needed to for patch 2
anyway), and resend so I can get this into my -next tree for people to
start testing and basing their work on?

sorry this has taken so long, and thanks for sticking with it.

greg k-h

Alexander Duyck Jan. 18, 2019, 7 p.m. UTC | #6

On Fri, 2019-01-18 at 16:54 +0100, Greg KH wrote:
> On Wed, Dec 12, 2018 at 04:44:58PM -0800, Alexander Duyck wrote:
> > Add an additional bit flag to the device struct named "dead".
> > 
> > This additional flag provides a guarantee that when a device_del is
> > executed on a given interface an async worker will not attempt to attach
> > the driver following the earlier device_del call. Previously this
> > guarantee was not present and could result in the device_del call
> > attempting to remove a driver from an interface only to have the async
> > worker attempt to probe the driver later when it finally completes the
> > asynchronous probe call.
> > 
> > One additional change added was that I pulled the check for dev->driver
> > out of the __device_attach_driver call and instead placed it in the
> > __device_attach_async_helper call. This was motivated by the fact that the
> > only other caller of this, __device_attach, had already taken the
> > device_lock() and checked for dev->driver. Instead of testing for this
> > twice in this path it makes more sense to just consolidate the dev->dead
> > and dev->driver checks together into one set of checks.
> > 
> > Reviewed-by: Dan Williams <[e-mail]>
> > Signed-off-by: Alexander Duyck <[e-mail]>
> > Reviewed-by: Rafael J. Wysocki <[e-mail]>
> > ---
> >  drivers/base/core.c    |   11 +++++++++++
> >  drivers/base/dd.c      |   22 +++++++++++-----------
> >  include/linux/device.h |    5 +++++
> >  3 files changed, 27 insertions(+), 11 deletions(-)
> > 
> > diff --git a/drivers/base/core.c b/drivers/base/core.c
> > index 0073b09bb99f..950e25495726 100644
> > --- a/drivers/base/core.c
> > +++ b/drivers/base/core.c
> > @@ -2080,6 +2080,17 @@ void device_del(struct device *dev)
> >  	struct kobject *glue_dir = NULL;
> >  	struct class_interface *class_intf;
> >  
> > +	/*
> > +	 * Hold the device lock and set the "dead" flag to guarantee that
> > +	 * the update behavior is consistent with the other bitfields near
> > +	 * it and that we cannot have an asynchronous probe routine trying
> > +	 * to run while we are tearing out the bus/class/sysfs from
> > +	 * underneath the device.
> > +	 */
> > +	device_lock(dev);
> > +	dev->dead = true;
> > +	device_unlock(dev);
> > +
> >  	/* Notify clients of device removal.  This call must come
> >  	 * before dpm_sysfs_remove().
> >  	 */
> > diff --git a/drivers/base/dd.c b/drivers/base/dd.c
> > index 88713f182086..74c194ac99df 100644
> > --- a/drivers/base/dd.c
> > +++ b/drivers/base/dd.c
> > @@ -731,15 +731,6 @@ static int __device_attach_driver(struct device_driver *drv, void *_data)
> >  	bool async_allowed;
> >  	int ret;
> >  
> > -	/*
> > -	 * Check if device has already been claimed. This may
> > -	 * happen with driver loading, device discovery/registration,
> > -	 * and deferred probe processing happens all at once with
> > -	 * multiple threads.
> > -	 */
> > -	if (dev->driver)
> > -		return -EBUSY;
> > -
> >  	ret = driver_match_device(drv, dev);
> >  	if (ret == 0) {
> >  		/* no match */
> > @@ -774,6 +765,15 @@ static void __device_attach_async_helper(void *_dev, async_cookie_t cookie)
> >  
> >  	device_lock(dev);
> >  
> > +	/*
> > +	 * Check if device has already been removed or claimed. This may
> > +	 * happen with driver loading, device discovery/registration,
> > +	 * and deferred probe processing happens all at once with
> > +	 * multiple threads.
> > +	 */
> > +	if (dev->dead || dev->driver)
> > +		goto out_unlock;
> > +
> >  	if (dev->parent)
> >  		pm_runtime_get_sync(dev->parent);
> >  
> > @@ -784,7 +784,7 @@ static void __device_attach_async_helper(void *_dev, async_cookie_t cookie)
> >  
> >  	if (dev->parent)
> >  		pm_runtime_put(dev->parent);
> > -
> > +out_unlock:
> >  	device_unlock(dev);
> >  
> >  	put_device(dev);
> > @@ -897,7 +897,7 @@ static int __driver_attach(struct device *dev, void *data)
> >  	if (dev->parent && dev->bus->need_parent_lock)
> >  		device_lock(dev->parent);
> >  	device_lock(dev);
> > -	if (!dev->driver)
> > +	if (!dev->dead && !dev->driver)
> >  		driver_probe_device(drv, dev);
> >  	device_unlock(dev);
> >  	if (dev->parent && dev->bus->need_parent_lock)
> > diff --git a/include/linux/device.h b/include/linux/device.h
> > index 1b25c7a43f4c..f73dad81e811 100644
> > --- a/include/linux/device.h
> > +++ b/include/linux/device.h
> > @@ -957,6 +957,10 @@ struct dev_links_info {
> >   *              device.
> >   * @dma_coherent: this particular device is dma coherent, even if the
> >   *		architecture supports non-coherent devices.
> > + * @dead:	This device is currently either in the process of or has
> > + *		been removed from the system. Any asynchronous events
> > + *		scheduled for this device should exit without taking any
> > + *		action.
> >   *
> >   * At the lowest level, every device in a Linux system is represented by an
> >   * instance of struct device. The device structure contains the information
> > @@ -1051,6 +1055,7 @@ struct device {
> >      defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
> >  	bool			dma_coherent:1;
> >  #endif
> > +	bool			dead:1;
> 
> This really should live in the struct device_private structure, as
> nothing outside of the driver core should care about this, or touch it.
> 
> A number of other bitfields should also move there as well, your's isn't
> the only one that I missed this for.
> 
> So can you make that quick change, and rebase (you needed to for patch 2
> anyway), and resend so I can get this into my -next tree for people to
> start testing and basing their work on?
> 
> sorry this has taken so long, and thanks for sticking with it.
> 
> greg k-h

Okay. I will try to work it into my schedule and hopefully have the
updated patches ready sometime early next week.

Thanks.

- Alex

Patch

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 0073b09bb99f..950e25495726 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -2080,6 +2080,17 @@  void device_del(struct device *dev)
 	struct kobject *glue_dir = NULL;
 	struct class_interface *class_intf;
 
+	/*
+	 * Hold the device lock and set the "dead" flag to guarantee that
+	 * the update behavior is consistent with the other bitfields near
+	 * it and that we cannot have an asynchronous probe routine trying
+	 * to run while we are tearing out the bus/class/sysfs from
+	 * underneath the device.
+	 */
+	device_lock(dev);
+	dev->dead = true;
+	device_unlock(dev);
+
 	/* Notify clients of device removal.  This call must come
 	 * before dpm_sysfs_remove().
 	 */
diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index 88713f182086..74c194ac99df 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -731,15 +731,6 @@  static int __device_attach_driver(struct device_driver *drv, void *_data)
 	bool async_allowed;
 	int ret;
 
-	/*
-	 * Check if device has already been claimed. This may
-	 * happen with driver loading, device discovery/registration,
-	 * and deferred probe processing happens all at once with
-	 * multiple threads.
-	 */
-	if (dev->driver)
-		return -EBUSY;
-
 	ret = driver_match_device(drv, dev);
 	if (ret == 0) {
 		/* no match */
@@ -774,6 +765,15 @@  static void __device_attach_async_helper(void *_dev, async_cookie_t cookie)
 
 	device_lock(dev);
 
+	/*
+	 * Check if device has already been removed or claimed. This may
+	 * happen with driver loading, device discovery/registration,
+	 * and deferred probe processing happens all at once with
+	 * multiple threads.
+	 */
+	if (dev->dead || dev->driver)
+		goto out_unlock;
+
 	if (dev->parent)
 		pm_runtime_get_sync(dev->parent);
 
@@ -784,7 +784,7 @@  static void __device_attach_async_helper(void *_dev, async_cookie_t cookie)
 
 	if (dev->parent)
 		pm_runtime_put(dev->parent);
-
+out_unlock:
 	device_unlock(dev);
 
 	put_device(dev);
@@ -897,7 +897,7 @@  static int __driver_attach(struct device *dev, void *data)
 	if (dev->parent && dev->bus->need_parent_lock)
 		device_lock(dev->parent);
 	device_lock(dev);
-	if (!dev->driver)
+	if (!dev->dead && !dev->driver)
 		driver_probe_device(drv, dev);
 	device_unlock(dev);
 	if (dev->parent && dev->bus->need_parent_lock)
diff --git a/include/linux/device.h b/include/linux/device.h
index 1b25c7a43f4c..f73dad81e811 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -957,6 +957,10 @@  struct dev_links_info {
  *              device.
  * @dma_coherent: this particular device is dma coherent, even if the
  *		architecture supports non-coherent devices.
+ * @dead:	This device is currently either in the process of or has
+ *		been removed from the system. Any asynchronous events
+ *		scheduled for this device should exit without taking any
+ *		action.
  *
  * At the lowest level, every device in a Linux system is represented by an
  * instance of struct device. The device structure contains the information
@@ -1051,6 +1055,7 @@  struct device {
     defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
 	bool			dma_coherent:1;
 #endif
+	bool			dead:1;
 };
 
 static inline struct device *kobj_to_dev(struct kobject *kobj)