[PATCH 4.9 15/24] ata: pata_marvell: Check the bmdma_addr beforing reading

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

From: Zheyu Ma <zheyuma97@gmail.com>

commit aafa9f958342db36c17ac2a7f1b841032c96feb4 upstream.

Before detecting the cable type on the dma bar, the driver should check
whether the 'bmdma_addr' is zero, which means the adapter does not
support DMA, otherwise we will get the following error:

[    5.146634] Bad IO access at port 0x1 (return inb(port))
[    5.147206] WARNING: CPU: 2 PID: 303 at lib/iomap.c:44 ioread8+0x4a/0x60
[    5.150856] RIP: 0010:ioread8+0x4a/0x60
[    5.160238] Call Trace:
[    5.160470]  <TASK>
[    5.160674]  marvell_cable_detect+0x6e/0xc0 [pata_marvell]
[    5.161728]  ata_eh_recover+0x3520/0x6cc0
[    5.168075]  ata_do_eh+0x49/0x3c0

Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/ata/pata_marvell.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/ata/pata_marvell.c
+++ b/drivers/ata/pata_marvell.c
@@ -82,6 +82,8 @@ static int marvell_cable_detect(struct a
 	switch(ap->port_no)
 	{
 	case 0:
+		if (!ap->ioaddr.bmdma_addr)
+			return ATA_CBL_PATA_UNK;
 		if (ioread8(ap->ioaddr.bmdma_addr + 1) & 1)
 			return ATA_CBL_PATA40;
 		return ATA_CBL_PATA80;