[PATCH v6 01/19] dmaengine: ti: k3-udma: Fix sporadic crash on AM62x

[Sai Sree Kartheek Adivi]

From: Vignesh Raghavendra <vigneshr at ti.com>

ring_init_data is declared on stack and thus can contain garbage which
can lead to k3_ringacc_dmarings use junk address for ringrt base leading
to below crash during ring pop

[    1.998239] cadence-qspi fc40000.spi: couldn't determine phase-detect-selector
[    2.532106] Unable to handle kernel paging request at virtual address ffff800081a84b98
[    2.540051] Mem abort info:
[...]
[    2.629987] Workqueue: events_unbound deferred_probe_work_func
[    2.635832] pstate: 800000c5 (Nzcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[    2.642787] pc : k3_ringacc_ring_pop+0x48/0x94
[    2.647234] lr : udma_pop_from_ring+0x7c/0xb4
[...]
[    2.726250] Call trace:
[    2.728691]  k3_ringacc_ring_pop+0x48/0x94
[    2.732786]  udma_ring_irq_handler+0x34/0x218
[    2.737141]  __handle_irq_event_percpu+0x60/0x14c
[    2.741846]  handle_irq_event+0x4c/0xa8

Fix this by explicitly initializing the variable to 0.

Reported-by: Rishikesh Donadkar <r-donadkar at ti.com>
Reported-by: Kendall Willis <k-willis at ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr at ti.com>
Signed-off-by: Sai Sree Kartheek Adivi <s-adivi at ti.com>
---
 drivers/dma/ti/k3-udma.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/dma/ti/k3-udma.c b/drivers/dma/ti/k3-udma.c
index c964ebfcf3b68..3e9792136906a 100644
--- a/drivers/dma/ti/k3-udma.c
+++ b/drivers/dma/ti/k3-udma.c
@@ -5484,7 +5484,7 @@ static int udma_probe(struct platform_device *pdev)
 	if (ud->match_data->type == DMA_TYPE_UDMA) {
 		ud->ringacc = of_k3_ringacc_get_by_phandle(dev->of_node, "ti,ringacc");
 	} else {
-		struct k3_ringacc_init_data ring_init_data;
+		struct k3_ringacc_init_data ring_init_data = { 0 };
 
 		ring_init_data.tisci = ud->tisci_rm.tisci;
 		ring_init_data.tisci_dev_id = ud->tisci_rm.tisci_dev_id;
-- 
2.53.0