From: Nicolas Frayer <nfrayer@xxxxxxxxxxxx>
[ Upstream commit 5f1732a8683c1da8faaa90d6ffc3bd6d33013a58 ]
When the k3 ring accelerator driver has been modified to add module build
support, try_module_get() and module_put() have been added to update the
module refcnt. One code path has not been updated and it has introduced
an issue where the refcnt is decremented by module_put() in
k3_ringacc_ring_free() without being incremented previously.
Adding try_module_get() to k3_dmaring_request_dual_ring() ensures the
refcnt is kept up to date.
Fixes: c07f216a8b72 ("soc: ti: k3-ringacc: Allow the driver to be built as module")
Signed-off-by: Nicolas Frayer <nfrayer@xxxxxxxxxxxx>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@xxxxxxxxx>
Link: https://lore.kernel.org/r/20221230001404.10902-1-nfrayer@xxxxxxxxxxxx
Signed-off-by: Nishanth Menon <nm@xxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/soc/ti/k3-ringacc.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/soc/ti/k3-ringacc.c b/drivers/soc/ti/k3-ringacc.c
index e01e4d815230a..8f131368a7586 100644
--- a/drivers/soc/ti/k3-ringacc.c
+++ b/drivers/soc/ti/k3-ringacc.c
@@ -406,6 +406,11 @@ static int k3_dmaring_request_dual_ring(struct k3_ringacc *ringacc, int fwd_id,
mutex_lock(&ringacc->req_lock);
+ if (!try_module_get(ringacc->dev->driver->owner)) {
+ ret = -EINVAL;
+ goto err_module_get;
+ }
+
if (test_bit(fwd_id, ringacc->rings_inuse)) {
ret = -EBUSY;
goto error;
@@ -421,6 +426,8 @@ static int k3_dmaring_request_dual_ring(struct k3_ringacc *ringacc, int fwd_id,
return 0;
error:
+ module_put(ringacc->dev->driver->owner);
+err_module_get:
mutex_unlock(&ringacc->req_lock);
return ret;
}
--
2.39.2
