So, just reverted this patch. On Wed, Jul 20, 2016 at 06:59:23AM +0800, tom.t...@gmail.com wrote: > From: Tom Yan <tom.t...@gmail.com> > > Commit 7780081c1f04 ("libata-scsi: Set information sense field for > invalid parameter") changed how ata_mselect_*() make sure read-only > bits are not modified. The new implementation introduced a bug that > the read-only bits in the byte that has a changeable bit will not > be checked. > > Added the necessary check, with comments explaining the heuristic. > > Signed-off-by: Tom Yan <tom.t...@gmail.com> > > diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c > index 06afe63..b47c3ce 100644 > --- a/drivers/ata/libata-scsi.c > +++ b/drivers/ata/libata-scsi.c > @@ -3617,8 +3617,18 @@ static int ata_mselect_caching(struct ata_queued_cmd > *qc, > */ > ata_msense_caching(dev->id, mpage, false); > for (i = 0; i < CACHE_MPAGE_LEN - 2; i++) { > - if (i == 0) > - continue; > + /* Check the first byte */ > + if (i == 0) { > + /* except the WCE bit */ > + if (mpage[i + 2] & 0xfb != buf[i] & 0xfb) {
This not only triggered compiler warning but is actually wrong. The above is mpage[i + 1] & (0xfb != buf[i]) & 0xfb which is non-sensical. So, this patch wasn't tested at all. Not even compile test. Please don't do this. Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html