Commits
Sebastian Andrzej Siewior committed 2df69484285
USB: cdc-wdm: don't enable interrupts in USB-giveback
In the code path
__usb_hcd_giveback_urb()
-> wdm_in_callback()
-> service_outstanding_interrupt()
The function service_outstanding_interrupt() will unconditionally enable
interrupts during unlock and invoke usb_submit_urb() with GFP_KERNEL.
If the HCD completes in BH (like ehci does) then the context remains
atomic due local_bh_disable() and enabling interrupts does not change
this.
Defer the error case handling to a workqueue as suggested by Oliver
Neukum. In case of an error the worker performs the read out and wakes
the user.
Fixes: c1da59dad0eb ("cdc-wdm: Clear read pipeline in case of error")
Cc: Robert Foss <robert.foss@collabora.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>