[PATCH 2/2] mtd: nand: ecc-hamming: Fix the double counting of ECC stat

From: YouChing Lin
Date: Mon May 10 2021 - 22:17:39 EST


If you use SPI-NAND with SW-ECC engine, the ECC related statistics
(ecc_stats.failed & ecc_stats.corrected) will be doubled, because
those numbers will be double-counted in ecc-sw-hamming.c and
drivers/mtd/nand/spi/core.c.

This can be found by using nandtest/nandbiterrs validation.

Signed-off-by: YouChing Lin <ycllin@xxxxxxxxxxx>
---
drivers/mtd/nand/ecc-sw-hamming.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/mtd/nand/ecc-sw-hamming.c b/drivers/mtd/nand/ecc-sw-hamming.c
index a7655b6..e8a30cf 100644
--- a/drivers/mtd/nand/ecc-sw-hamming.c
+++ b/drivers/mtd/nand/ecc-sw-hamming.c
@@ -625,11 +625,12 @@ static int nand_ecc_sw_hamming_finish_io_req(struct nand_device *nand,
&ecccode[i],
&ecccalc[i]);
if (stat < 0) {
- mtd->ecc_stats.failed++;
- } else {
- mtd->ecc_stats.corrected += stat;
- max_bitflips = max_t(unsigned int, max_bitflips, stat);
+ nand_ecc_restore_req(&engine_conf->req_ctx, req);
+
+ return -EBADMSG;
}
+
+ max_bitflips = max_t(unsigned int, max_bitflips, stat);
}

nand_ecc_restore_req(&engine_conf->req_ctx, req);
--
1.9.1