Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Junxiao Chang <junxiao.chang@intel.com>
To:     peppe.cavallaro@st.com, alexandre.torgue@foss.st.com,
        joabreu@synopsys.com, davem@davemloft.net, edumazet@google.com,
        kuba@kernel.org, pabeni@redhat.com, mcoquelin.stm32@gmail.com,
        Joao.Pinto@synopsys.com, netdev@vger.kernel.org,
        linux-stm32@st-md-mailman.stormreply.com,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
Cc:     junxiao.chang@intel.com
Subject: [PATCH net-next 1/2] net: stmmac: fix unsafe MTL DMA macro
Date:   Fri, 21 Oct 2022 19:47:10 +0800
Message-Id: <20221021114711.1610797-1-junxiao.chang@intel.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Macro like "#define abc(x) (x, x)" is unsafe which might introduce
side effects. Each MTL RxQ DMA channel mask is 4 bits, so using
(0xf << chan) instead of GENMASK(x + 3, x) to avoid unsafe macro.

Fixes: d43042f4da3e ("net: stmmac: mapping mtl rx to dma channel")
Signed-off-by: Junxiao Chang <junxiao.chang@intel.com>
---
 drivers/net/ethernet/stmicro/stmmac/dwmac4.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4.h b/drivers/net/ethernet/stmicro/stmmac/dwmac4.h
index 71dad409f78b0..3c1490408a1c3 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4.h
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4.h
@@ -333,7 +333,7 @@ enum power_event {
 #define MTL_RXQ_DMA_MAP1		0x00000c34 /* queue 4 to 7 */
 #define MTL_RXQ_DMA_Q04MDMACH_MASK	GENMASK(3, 0)
 #define MTL_RXQ_DMA_Q04MDMACH(x)	((x) << 0)
-#define MTL_RXQ_DMA_QXMDMACH_MASK(x)	GENMASK(11 + (8 * ((x) - 1)), 8 * (x))
+#define MTL_RXQ_DMA_QXMDMACH_MASK(x)	(0xf << 8 * (x))
 #define MTL_RXQ_DMA_QXMDMACH(chan, q)	((chan) << (8 * (q)))
 
 #define MTL_CHAN_BASE_ADDR		0x00000d00
-- 
2.25.1