Messages in this thread Patch in this message | | | From | Greg Kroah-Hartman <> | Subject | [PATCH 3.18 03/24] mtd: nand: gpmi: Fix failure when a erased page has a bitflip at BBM | Date | Fri, 2 Mar 2018 09:51:00 +0100 |
| |
3.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: Sascha Hauer <s.hauer@pengutronix.de>
[ Upstream commit fdf2e821052958a114618a95ab18a300d0b080cb ]
When erased subpages are read then the BCH decoder returns STATUS_ERASED if they are all empty, or STATUS_UNCORRECTABLE if there are bitflips. When there are bitflips, we have to set these bits again to show the upper layers a completely erased page. When a bitflip happens in the exact byte where the bad block marker is, then this byte is swapped with another byte in block_mark_swapping(). The correction code then detects a bitflip in another subpage and no longer corrects the bitflip where it really happens.
Correct this behaviour by calling block_mark_swapping() after the bitflips have been corrected.
In our case UBIFS failed with this bug because it expects erased pages to be really empty:
UBIFS error (pid 187): ubifs_scan: corrupt empty space at LEB 36:118735 UBIFS error (pid 187): ubifs_scanned_corruption: corruption at LEB 36:118735 UBIFS error (pid 187): ubifs_scanned_corruption: first 8192 bytes from LEB 36:118735 UBIFS error (pid 187): ubifs_scan: LEB 36 scanning failed UBIFS error (pid 187): do_commit: commit failed, error -117
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Reviewed-by: Richard Weinberger <richard@nod.at> Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- drivers/mtd/nand/gpmi-nand/gpmi-nand.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
--- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c +++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c @@ -1025,9 +1025,6 @@ static int gpmi_ecc_read_page(struct mtd return ret; } - /* handle the block mark swapping */ - block_mark_swapping(this, payload_virt, auxiliary_virt); - /* Loop over status bytes, accumulating ECC status. */ status = auxiliary_virt + nfc_geo->auxiliary_status_offset; @@ -1043,6 +1040,9 @@ static int gpmi_ecc_read_page(struct mtd max_bitflips = max_t(unsigned int, max_bitflips, *status); } + /* handle the block mark swapping */ + block_mark_swapping(this, buf, auxiliary_virt); + if (oob_required) { /* * It's time to deliver the OOB bytes. See gpmi_ecc_read_oob()
| |