diff options
| author | Andy Shevchenko | 2020-07-23 16:02:46 +0300 |
|---|---|---|
| committer | Lee Jones | 2020-08-13 07:50:56 +0100 |
| commit | 3d858942250820b9adc35f963a257481d6d4c81d (patch) | |
| tree | c7a5416aa7013be8a92621c41d580ef1ebb8fb83 | |
| parent | 77b3ddab713a2276c789a8e1beb339ce185cebc2 (diff) | |
mfd: dln2: Run event handler loop under spinlock
The event handler loop must be run with interrupts disabled.
Otherwise we will have a warning:
[ 1970.785649] irq 31 handler lineevent_irq_handler+0x0/0x20 enabled interrupts
[ 1970.792739] WARNING: CPU: 0 PID: 0 at kernel/irq/handle.c:159 __handle_irq_event_percpu+0x162/0x170
[ 1970.860732] RIP: 0010:__handle_irq_event_percpu+0x162/0x170
...
[ 1970.946994] Call Trace:
[ 1970.949446] <IRQ>
[ 1970.951471] handle_irq_event_percpu+0x2c/0x80
[ 1970.955921] handle_irq_event+0x23/0x43
[ 1970.959766] handle_simple_irq+0x57/0x70
[ 1970.963695] generic_handle_irq+0x42/0x50
[ 1970.967717] dln2_rx+0xc1/0x210 [dln2]
[ 1970.971479] ? usb_hcd_unmap_urb_for_dma+0xa6/0x1c0
[ 1970.976362] __usb_hcd_giveback_urb+0x77/0xe0
[ 1970.980727] usb_giveback_urb_bh+0x8e/0xe0
[ 1970.984837] tasklet_action_common.isra.0+0x4a/0xe0
...
Recently xHCI driver switched to tasklets in the commit 36dc01657b49
("usb: host: xhci: Support running urb giveback in tasklet context").
The handle_irq_event_* functions are expected to be called with interrupts
disabled and they rightfully complain here because we run in tasklet context
with interrupts enabled.
Use a event spinlock to protect event handler from being interrupted.
Note, that there are only two users of this GPIO and ADC drivers and both of
them are using generic_handle_irq() which makes above happen.
Fixes: 338a12814297 ("mfd: Add support for Diolan DLN-2 devices")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
| -rw-r--r-- | drivers/mfd/dln2.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/mfd/dln2.c b/drivers/mfd/dln2.c index 39276fa626d2..83e676a096dc 100644 --- a/drivers/mfd/dln2.c +++ b/drivers/mfd/dln2.c @@ -287,7 +287,11 @@ static void dln2_rx(struct urb *urb) len = urb->actual_length - sizeof(struct dln2_header); if (handle == DLN2_HANDLE_EVENT) { + unsigned long flags; + + spin_lock_irqsave(&dln2->event_cb_lock, flags); dln2_run_event_callbacks(dln2, id, echo, data, len); + spin_unlock_irqrestore(&dln2->event_cb_lock, flags); } else { /* URB will be re-submitted in _dln2_transfer (free_rx_slot) */ if (dln2_transfer_complete(dln2, urb, handle, echo)) |