commit 44d9b3f584c59a606b521e7274e658d5b866c699 upstream.
When `jr3_pci_detach()` is called during device removal, it calls `del_timer_sync()` to stop the timer, but the timer expiry function always reschedules the timer, so the synchronization is ineffective.
Add a member `bool timer_enable` to the device private data to indicate whether the timer should be restarted. Use the main comedi device spin-lock for synchronization, as that is already used by the timer expiry function. (The upstream commit called `timer_shutdown_sync()` instead of `del_timer_sync()`, but that is not available.)
Fixes: 07b509e6584a5 ("Staging: comedi: add jr3_pci driver") Cc: stable stable@kernel.org Signed-off-by: Ian Abbott abbotti@mev.co.uk Link: https://lore.kernel.org/r/20250415123901.13483-1-abbotti@mev.co.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/staging/comedi/drivers/jr3_pci.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/staging/comedi/drivers/jr3_pci.c b/drivers/staging/comedi/drivers/jr3_pci.c index 7a02c4fa3cda..cc1232609f32 100644 --- a/drivers/staging/comedi/drivers/jr3_pci.c +++ b/drivers/staging/comedi/drivers/jr3_pci.c @@ -88,6 +88,7 @@ struct jr3_pci_poll_delay { struct jr3_pci_dev_private { struct timer_list timer; struct comedi_device *dev; + bool timer_enable; };
union jr3_pci_single_range { @@ -612,10 +613,11 @@ static void jr3_pci_poll_dev(struct timer_list *t) delay = sub_delay.max; } } + if (devpriv->timer_enable) { + devpriv->timer.expires = jiffies + msecs_to_jiffies(delay); + add_timer(&devpriv->timer); + } spin_unlock_irqrestore(&dev->spinlock, flags); - - devpriv->timer.expires = jiffies + msecs_to_jiffies(delay); - add_timer(&devpriv->timer); }
static struct jr3_pci_subdev_private * @@ -764,6 +766,7 @@ static int jr3_pci_auto_attach(struct comedi_device *dev, devpriv->dev = dev; timer_setup(&devpriv->timer, jr3_pci_poll_dev, 0); devpriv->timer.expires = jiffies + msecs_to_jiffies(1000); + devpriv->timer_enable = true; add_timer(&devpriv->timer);
return 0; @@ -773,8 +776,12 @@ static void jr3_pci_detach(struct comedi_device *dev) { struct jr3_pci_dev_private *devpriv = dev->private;
- if (devpriv) + if (devpriv) { + spin_lock_bh(&dev->spinlock); + devpriv->timer_enable = false; + spin_unlock_bh(&dev->spinlock); del_timer_sync(&devpriv->timer); + }
comedi_pci_detach(dev); }