* [PATCH v2 1/3] mtd: spinand: Stop using spinand->oobbuf for buffering bad block markers
[not found] <20200217155213.5594-1-frieder.schrempf@kontron.de>
@ 2020-02-17 15:53 ` Schrempf Frieder
2020-02-17 15:54 ` [PATCH v2 3/3] mtd: spinand: Don not erase the block before writing a bad block marker Schrempf Frieder
1 sibling, 0 replies; 3+ messages in thread
From: Schrempf Frieder @ 2020-02-17 15:53 UTC (permalink / raw)
To: Boris Brezillon, Schrempf Frieder, Jeff Kletsky, liaoweixiong,
Miquel Raynal
Cc: stable@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-mtd@lists.infradead.org, Richard Weinberger
From: Frieder Schrempf <frieder.schrempf@kontron.de>
For reading and writing the bad block markers, spinand->oobbuf is
currently used as a buffer for the marker bytes. During the
underlying read and write operations to actually get/set the content
of the OOB area, the content of spinand->oobbuf is reused and changed
by accessing it through spinand->oobbuf and/or spinand->databuf.
This is a flaw in the original design of the SPI MEM core and at the
latest from 13c15e07eedf ("mtd: spinand: Handle the case where
PROGRAM LOAD does not reset the cache") on, it results in not having
the bad block marker written at all, as the spinand->oobbuf is
cleared to 0xff after setting the marker bytes to zero.
To fix it, we now just store the two bytes for the marker on the
stack and let the read/write operations copy it from/to the page
buffer later.
Fixes: 7529df465248 ("mtd: nand: Add core infrastructure to support SPI NANDs")
Cc: stable@vger.kernel.org
Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
---
Changes in v2:
* Incorporate small improvements proposed by Boris
* Add Boris' R-b tag
---
drivers/mtd/nand/spi/core.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/drivers/mtd/nand/spi/core.c b/drivers/mtd/nand/spi/core.c
index 89f6beefb01c..de36cd7a5d7e 100644
--- a/drivers/mtd/nand/spi/core.c
+++ b/drivers/mtd/nand/spi/core.c
@@ -568,18 +568,18 @@ static int spinand_mtd_write(struct mtd_info *mtd, loff_t to,
static bool spinand_isbad(struct nand_device *nand, const struct nand_pos *pos)
{
struct spinand_device *spinand = nand_to_spinand(nand);
+ u8 marker[2] = { };
struct nand_page_io_req req = {
.pos = *pos,
- .ooblen = 2,
+ .ooblen = sizeof(marker),
.ooboffs = 0,
- .oobbuf.in = spinand->oobbuf,
+ .oobbuf.in = marker,
.mode = MTD_OPS_RAW,
};
- memset(spinand->oobbuf, 0, 2);
spinand_select_target(spinand, pos->target);
spinand_read_page(spinand, &req, false);
- if (spinand->oobbuf[0] != 0xff || spinand->oobbuf[1] != 0xff)
+ if (marker[0] != 0xff || marker[1] != 0xff)
return true;
return false;
@@ -603,11 +603,12 @@ static int spinand_mtd_block_isbad(struct mtd_info *mtd, loff_t offs)
static int spinand_markbad(struct nand_device *nand, const struct nand_pos *pos)
{
struct spinand_device *spinand = nand_to_spinand(nand);
+ u8 marker[2] = { };
struct nand_page_io_req req = {
.pos = *pos,
.ooboffs = 0,
- .ooblen = 2,
- .oobbuf.out = spinand->oobbuf,
+ .ooblen = sizeof(marker),
+ .oobbuf.out = marker,
};
int ret;
@@ -622,7 +623,6 @@ static int spinand_markbad(struct nand_device *nand, const struct nand_pos *pos)
spinand_erase_op(spinand, pos);
- memset(spinand->oobbuf, 0, 2);
return spinand_write_page(spinand, &req);
}
--
2.17.1
^ permalink raw reply related [flat|nested] 3+ messages in thread* [PATCH v2 3/3] mtd: spinand: Don not erase the block before writing a bad block marker
[not found] <20200217155213.5594-1-frieder.schrempf@kontron.de>
2020-02-17 15:53 ` [PATCH v2 1/3] mtd: spinand: Stop using spinand->oobbuf for buffering bad block markers Schrempf Frieder
@ 2020-02-17 15:54 ` Schrempf Frieder
2020-02-17 17:24 ` Boris Brezillon
1 sibling, 1 reply; 3+ messages in thread
From: Schrempf Frieder @ 2020-02-17 15:54 UTC (permalink / raw)
To: Boris Brezillon, Schrempf Frieder, Jeff Kletsky, liaoweixiong,
Miquel Raynal
Cc: stable@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-mtd@lists.infradead.org, Richard Weinberger
From: Frieder Schrempf <frieder.schrempf@kontron.de>
Currently when marking a block, we use spinand_erase_op() to erase
the block before writing the marker to the OOB area. Doing so without
waiting for the operation to finish can lead to the marking failing
silently and no bad block marker being written to the flash.
In fact we don't need to do an erase at all before writing the BBM.
The ECC is disabled for the raw access to the OOB data and we don't
need to work around any issues with chips reporting ECC errors as it
is known to be the case for raw NAND.
Fixes: 7529df465248 ("mtd: nand: Add core infrastructure to support SPI NANDs")
Cc: stable@vger.kernel.org
Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
---
Changes in v2:
* Instead of waiting for the erase operation to finish, just don't
do an erase at all, as it is not needed.
* Update the commit message
---
drivers/mtd/nand/spi/core.c | 3 ---
1 file changed, 3 deletions(-)
diff --git a/drivers/mtd/nand/spi/core.c b/drivers/mtd/nand/spi/core.c
index a94287884453..8dda51bbdd11 100644
--- a/drivers/mtd/nand/spi/core.c
+++ b/drivers/mtd/nand/spi/core.c
@@ -613,7 +613,6 @@ static int spinand_markbad(struct nand_device *nand, const struct nand_pos *pos)
};
int ret;
- /* Erase block before marking it bad. */
ret = spinand_select_target(spinand, pos->target);
if (ret)
return ret;
@@ -622,8 +621,6 @@ static int spinand_markbad(struct nand_device *nand, const struct nand_pos *pos)
if (ret)
return ret;
- spinand_erase_op(spinand, pos);
-
return spinand_write_page(spinand, &req);
}
--
2.17.1
^ permalink raw reply related [flat|nested] 3+ messages in thread