Commits
Konrad Rzeszutek Wilk committed a96d627abaa
pci: Introduce __pci_reset_function_locked to be used when holding device_lock.
The use case of this is when a driver wants to call FLR when a device
is attached to it using the SysFS "bind" or "unbind" functionality.
The call chain when a user does "bind" looks as so:
echo "0000:01.07.0" > /sys/bus/pci/drivers/XXXX/bind
and ends up calling:
driver_bind:
device_lock(dev); <=== TAKES LOCK
XXXX_probe:
.. pci_enable_device()
...__pci_reset_function(), which calls
pci_dev_reset(dev, 0):
if (!0) {
device_lock(dev) <==== DEADLOCK
The __pci_reset_function_locked function allows the the drivers
'probe' function to call the "pci_reset_function" while still holding
the driver mutex lock.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>