openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

usb: usbfs: use irqsave() in USB's complete callback 

The USB completion callback does not disable interrupts while acquiring
the lock. We want to remove the local_irq_disable() invocation from
__usb_hcd_giveback_urb() and therefore it is required for the callback
handler to disable the interrupts while acquiring the lock.
The callback may be invoked either in IRQ or BH context depending on the
USB host controller.
Use the _irqsave() variant of the locking primitives.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Sebastian Andrzej Siewior 2018-06-25 00:08:37 +02:00 committed by Greg Kroah-Hartman
parent 31adcb0a9c
commit 3f38dace1a
1 changed files with 3 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
drivers/usb/core/devio.c
View File

@ -585,9 +585,10 @@ static void async_completed(struct urb *urb)
struct siginfo sinfo;
struct pid *pid = NULL;
const struct cred *cred = NULL;
unsigned long flags;
int signr;
spin_lock(&ps->lock);
spin_lock_irqsave(&ps->lock, flags);
list_move_tail(&as->asynclist, &ps->async_completed);
as->status = urb->status;
signr = as->signr;
@ -611,7 +612,7 @@ static void async_completed(struct urb *urb)
cancel_bulk_urbs(ps, as->bulk_addr);
wake_up(&ps->wait);
spin_unlock(&ps->lock);
spin_unlock_irqrestore(&ps->lock, flags);
if (signr) {
kill_pid_info_as_cred(sinfo.si_signo, &sinfo, pid, cred);