On 2021-01-05 11:40, Miquel Raynal wrote:
Hello,
Greg KH gregkh@linuxfoundation.org wrote on Tue, 5 Jan 2021 11:31:26 +0100:
On Tue, Jan 05, 2021 at 11:18:21AM +0100, Felix Fietkau wrote:
This reverts stable commit baad618d078c857f99cc286ea249e9629159901f.
This commit is adding lines to spinand_write_to_cache_op, wheras the upstream commit 868cbe2a6dcee451bd8f87cbbb2a73cf463b57e5 that this was supposed to backport was touching spinand_read_from_cache_op. It causes a crash on writing OOB data by attempting to write to read-only kernel memory.
Cc: Miquel Raynal miquel.raynal@bootlin.com Signed-off-by: Felix Fietkau nbd@nbd.name
drivers/mtd/nand/spi/core.c | 4 ---- 1 file changed, 4 deletions(-)
So the backport to 5.10.y broke, but not the backport to 4.19.y or 5.4.y? Can you provide a "correct" backport for this instead of just removing this fix?
Agreed, I think the proper way to handle the situation would be to move these three lines to spinand_read_from_cache_op() instead of just getting rid of them.
But they have a similar line in spinand_read_from_cache_op already (in addition to some extra code for dealing with MTD_OPS_AUTO_OOB).
Please take another look at your commit 3d1f08b032dc, it really looks to me like you were just adding back a part of what you removed there. Maybe the proper solution is to add back the rest of it as well (the part that deals with MTD_OPS_AUTO_OOB) and leave the stable kernels alone.
- Felix