Hi Boris, On Fri, 11 May 2018 14:44:07 +0200, Boris Brezillon <boris.brezillon@xxxxxxxxxxx> wrote: > The ONFI spec clearly says that FAIL bit is only valid for PROGRAM, > ERASE and READ-with-on-die-ECC operations, and should be ignored > otherwise. > > It seems that checking it after sending a SET_FEATURES is a bad idea > because a previous READ, PROGRAM or ERASE op may have failed, and > depending on the implementation, the FAIL bit is not cleared until a > new READ, PROGRAM or ERASE is started. > > This leads to ->set_features() returning -EIO while it actually worked, > which can sometimes stop a batch of READ/PROGRAM ops. > > Note that we only fix the ->exec_op() path here, because some drivers > are abusing the NAND_STATUS_FAIL flag in their ->waitfunc() > implementation to propagate other kind of errors, like > wait-ready-timeout or controller-related errors. Let's not try to fix > those drivers since they worked fine so far. > > Fixes: 8878b126df76 ("mtd: nand: add ->exec_op() implementation") > Cc: stable@xxxxxxxxxxxxxxx > Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxx> > --- So we have no real way to know if a SET_FEATURES actually succeeded. I checked the ONFI spec and could not find anything. A GET_FEATURES will do the trick though (when supported). Acked-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>