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Subject[PATCH 1/3] driver core: Avoid binding drivers to dead devices
Commit 3451a495ef24 ("driver core: Establish order of operations for
device_add and device_del via bitflag") sought to prevent asynchronous
driver binding to a device which is being removed. It added a
per-device "dead" flag which is checked in the following code paths:

* asynchronous binding in __driver_attach_async_helper()
* synchronous binding in device_driver_attach()
* asynchronous binding in __device_attach_async_helper()

It did *not* check the flag upon:

* synchronous binding in __device_attach()

However __device_attach() may also be called asynchronously from:

deferred_probe_work_func()
bus_probe_device()
device_initial_probe()
__device_attach()

So if the commit's intention was to check the "dead" flag in all
asynchronous code paths, then a check is also necessary in
__device_attach(). Add the missing check.

Fixes: 3451a495ef24 ("driver core: Establish order of operations for device_add and device_del via bitflag")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v5.1+
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
---
drivers/base/dd.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index 9a1d940342ac4..31c668651e824 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -848,7 +848,9 @@ static int __device_attach(struct device *dev, bool allow_async)
int ret = 0;

device_lock(dev);
- if (dev->driver) {
+ if (dev->p->dead) {
+ goto out_unlock;
+ } else if (dev->driver) {
if (device_is_bound(dev)) {
ret = 1;
goto out_unlock;
--
2.27.0
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