[PATCH v2][linux-next] dmaengine: dw-axi-dmac: Fix uninitialized variable in axi_chan_block_xfer_start()

From: Tim Gardner
Date: Mon Oct 25 2021 - 14:17:25 EST


Coverity complains of an uninitialized variable:

5. uninit_use_in_call: Using uninitialized value config.dst_per when calling axi_chan_config_write. [show details]
6. uninit_use_in_call: Using uninitialized value config.hs_sel_src when calling axi_chan_config_write. [show details]
CID 121164 (#1-3 of 3): Uninitialized scalar variable (UNINIT)
7. uninit_use_in_call: Using uninitialized value config.src_per when calling axi_chan_config_write. [show details]
418 axi_chan_config_write(chan, &config);

Fix this by initializing the structure to 0 which should at least be benign in axi_chan_config_write(). Also fix
what looks like a cut-n-paste error when initializing config.hs_sel_dst.

Fixes: 824351668a413 ("dmaengine: dw-axi-dmac: support DMAX_NUM_CHANNELS > 8")
Cc: Eugeniy Paltsev <Eugeniy.Paltsev@xxxxxxxxxxxx>
Cc: Vinod Koul <vkoul@xxxxxxxxxx>
Cc: dmaengine@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Tim Gardner <tim.gardner@xxxxxxxxxxxxx>
---

v2 - Use static initializer for 'config'. Drop the memset() call.

---
drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
index 79572ec532ef..9a9194da0dcb 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
@@ -373,7 +373,7 @@ static void axi_chan_block_xfer_start(struct axi_dma_chan *chan,
struct axi_dma_desc *first)
{
u32 priority = chan->chip->dw->hdata->priority[chan->id];
- struct axi_dma_chan_config config;
+ struct axi_dma_chan_config config = {};
u32 irq_mask;
u8 lms = 0; /* Select AXI0 master for LLI fetching */

@@ -391,7 +391,7 @@ static void axi_chan_block_xfer_start(struct axi_dma_chan *chan,
config.tt_fc = DWAXIDMAC_TT_FC_MEM_TO_MEM_DMAC;
config.prior = priority;
config.hs_sel_dst = DWAXIDMAC_HS_SEL_HW;
- config.hs_sel_dst = DWAXIDMAC_HS_SEL_HW;
+ config.hs_sel_src = DWAXIDMAC_HS_SEL_HW;
switch (chan->direction) {
case DMA_MEM_TO_DEV:
dw_axi_dma_set_byte_halfword(chan, true);
--
2.33.1