From: Nicolas Frayer nfrayer@baylibre.com
[ 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@baylibre.com Reviewed-by: Peter Ujfalusi peter.ujfalusi@gmail.com Link: https://lore.kernel.org/r/20221230001404.10902-1-nfrayer@baylibre.com Signed-off-by: Nishanth Menon nm@ti.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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; }