[PATCH] EDAC/bluefield: dont use bluefield_edac_readl result on error

[David Thompson]

The "bluefield_edac_readl()" routine returns an uninitialized result
during error paths. In those cases the calling routine should not use
the uninitialized result. The driver should simply log the error, and
then return early.

Fixes: e41967575474 ("EDAC/bluefield: Use Arm SMC for EMI access on BlueField-2")
Signed-off-by: David Thompson <davthompson@xxxxxxxxxx>
Reviewed-by: Shravan Kumar Ramani <shravankr@xxxxxxxxxx>
---
 drivers/edac/bluefield_edac.c | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/drivers/edac/bluefield_edac.c b/drivers/edac/bluefield_edac.c
index 4942a240c30f..ae3bb7afa103 100644
--- a/drivers/edac/bluefield_edac.c
+++ b/drivers/edac/bluefield_edac.c
@@ -199,8 +199,10 @@ static void bluefield_gather_report_ecc(struct mem_ctl_info *mci,
 	 * error without the detailed information.
 	 */
 	err = bluefield_edac_readl(priv, MLXBF_SYNDROM, &dram_syndrom);
-	if (err)
+	if (err) {
 		dev_err(priv->dev, "DRAM syndrom read failed.\n");
+		return;
+	}
 
 	serr = FIELD_GET(MLXBF_SYNDROM__SERR, dram_syndrom);
 	derr = FIELD_GET(MLXBF_SYNDROM__DERR, dram_syndrom);
@@ -213,20 +215,26 @@ static void bluefield_gather_report_ecc(struct mem_ctl_info *mci,
 	}
 
 	err = bluefield_edac_readl(priv, MLXBF_ADD_INFO, &dram_additional_info);
-	if (err)
+	if (err) {
 		dev_err(priv->dev, "DRAM additional info read failed.\n");
+		return;
+	}
 
 	err_prank = FIELD_GET(MLXBF_ADD_INFO__ERR_PRANK, dram_additional_info);
 
 	ecc_dimm = (err_prank >= 2 && priv->dimm_ranks[0] <= 2) ? 1 : 0;
 
 	err = bluefield_edac_readl(priv, MLXBF_ERR_ADDR_0, &edea0);
-	if (err)
+	if (err) {
 		dev_err(priv->dev, "Error addr 0 read failed.\n");
+		return;
+	}
 
 	err = bluefield_edac_readl(priv, MLXBF_ERR_ADDR_1, &edea1);
-	if (err)
+	if (err) {
 		dev_err(priv->dev, "Error addr 1 read failed.\n");
+		return;
+	}
 
 	ecc_dimm_addr = ((u64)edea1 << 32) | edea0;
 
@@ -250,8 +258,10 @@ static void bluefield_edac_check(struct mem_ctl_info *mci)
 		return;
 
 	err = bluefield_edac_readl(priv, MLXBF_ECC_CNT, &ecc_count);
-	if (err)
+	if (err) {
 		dev_err(priv->dev, "ECC count read failed.\n");
+		return;
+	}
 
 	single_error_count = FIELD_GET(MLXBF_ECC_CNT__SERR_CNT, ecc_count);
 	double_error_count = FIELD_GET(MLXBF_ECC_CNT__DERR_CNT, ecc_count);
-- 
2.43.2