Re: [PATCH] ide: ide_port_wait_ready() fix

[Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>]

David Miller wrote:

> From: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
> Date: Tue, 11 Oct 2011 19:13:18 +0200
> 
> > From: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
> > Subject: [PATCH] ide: ide_port_wait_ready() fix
> > 
> > Fix for commit a20b2a4 ("ide: skip probe if there are no devices on
> > the port (v2)").  We must check for slave device before failing.
> > 
> > Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
> 
> This will mishandle the case where there is no slave in the device
> list.

I don't see it:

@ -598,7 +598,7 @@ static int ide_port_wait_ready(ide_hwif_
 {
 	const struct ide_tp_ops *tp_ops = hwif->tp_ops;
 	ide_drive_t *drive;
-	int i, rc;
+	int i, rc, prev_rc = 0;
 
 	printk(KERN_DEBUG "Probing IDE interface %s...\n", hwif->name);
 
@@ -623,8 +623,10 @@ static int ide_port_wait_ready(ide_hwif_
 			tp_ops->write_devctl(hwif, ATA_DEVCTL_OBS);
 			mdelay(2);
 			rc = ide_wait_not_busy(hwif, 35000);
-			if (rc)
+			if (prev_rc && rc)
 				goto out;
+			prev_rc = rc;
+			rc = 0;
 		} else
 			printk(KERN_DEBUG "%s: ide_wait_not_busy() skipped\n",
 					  drive->name);

If there is no slave device but there is a master device the code falls-through
and returns a success.

The patch fixes regression introduced in commit a20b2a4 as some esoteric
setups return ide_wait_not_busy() -ENODEV error on master device while there
is slave device present in the system.