[PATCH 2/2] soc: qcom: aoss: qmp_send() can't handle interruptions so stop pretending

From: Douglas Anderson
Date: Wed Aug 05 2020 - 16:13:00 EST

The function qmp_send() called wait_event_interruptible_timeout() to
wait for its interrupt. However, this function did not check for
-ERESTARTSYS and assumed that any non-zero return value meant that the
event happened.

While we could try to figure out how to handle interruptions by
figuring out how to cancel and/or undo our transfer in a race-free way
and then communicating this status back to all of our callers, that
seems like a whole lot of complexity. As I understand it the transfer
should happen rather quickly and if we're really hitting the 1 second
timeout we're in deep doggy doodoo anyway. Let's just use the
non-interruptible version of the function and call it good enough.

Found by code inspection. No known test cases expose the problem
described here.

Fixes: 2209481409b7 ("soc: qcom: Add AOSS QMP driver")
Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>

drivers/soc/qcom/qcom_aoss.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/soc/qcom/qcom_aoss.c b/drivers/soc/qcom/qcom_aoss.c
index 818cdf74a267..897f9f1c33ba 100644
--- a/drivers/soc/qcom/qcom_aoss.c
+++ b/drivers/soc/qcom/qcom_aoss.c
@@ -257,8 +257,8 @@ static int qmp_send(struct qmp *qmp, const void *data, size_t len, bool noirq)
time_left = readx_poll_timeout_atomic(qmp_message_empty, qmp,
is_empty, is_empty, 1U, 1000000U);
- time_left = wait_event_interruptible_timeout(qmp->event,
- qmp_message_empty(qmp), HZ);
+ time_left = wait_event_timeout(qmp->event, qmp_message_empty(qmp), HZ);
if (!time_left) {
dev_err(qmp->dev, "ucore did not ack channel\n");