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>
---Changes in v2:
    - Delete the useless 'else'
---
 drivers/ata/pata_marvell.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/ata/pata_marvell.c b/drivers/ata/pata_marvell.c
index 0c5a51970fbf..014ccb0f45dc 100644
--- a/drivers/ata/pata_marvell.c
+++ b/drivers/ata/pata_marvell.c
@@ -77,6 +77,8 @@ static int marvell_cable_detect(struct ata_port *ap)
 	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;
-- 
2.25.1

On 4/21/22 10:39, Zheyu Ma wrote:
> 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>
> ---Changes in v2:
>      - Delete the useless 'else'

Note for future contributions: The change log should be placed *after* 
the "---" that comes before the "diff" line below. Otherwise, the change 
log pollutes the commit message.

I fixed that and applied to for-5.18-fixes. Thanks.

> ---
>   drivers/ata/pata_marvell.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/ata/pata_marvell.c b/drivers/ata/pata_marvell.c
> index 0c5a51970fbf..014ccb0f45dc 100644
> --- a/drivers/ata/pata_marvell.c
> +++ b/drivers/ata/pata_marvell.c
> @@ -77,6 +77,8 @@ static int marvell_cable_detect(struct ata_port *ap)
>   	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;


-- 
Damien Le Moal
Western Digital Research

On Fri, Apr 22, 2022 at 7:48 AM Damien Le Moal
<damien.lemoal@opensource.wdc.com> wrote:
>
> On 4/21/22 10:39, Zheyu Ma wrote:
> > 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>
> > ---Changes in v2:
> >      - Delete the useless 'else'
>
> Note for future contributions: The change log should be placed *after*
> the "---" that comes before the "diff" line below. Otherwise, the change
> log pollutes the commit message.

Thank you for the reminder, I'll pay attention to this problem next time!

Zheyu Ma