Question about HighPoint RocketRAID 642L SCSI driver conflict with Linux AHCI driver

Question about HighPoint RocketRAID 642L SCSI driver conflict with Linux AHCI driver

[linux]

Dear Tejun Heo,

  This is HighPoint Linux Team. We found Linux AHCI driver since kernel 3.16
has added ID (0x06421103) to support RocketRAID 642L which is not what we
expected. If we want to load HighPoint RR642L RAID version Linux SCSI
driver, it becomes conflict each other. This affects our customers who need
to use our RAID version driver stack.
  
  Hence,  this is to ask Linux how to solve this conflict with AHCI driver?
and why Linux wants to add RR642L ID (0x06421103) into AHCI driver? Is there
any way to prevent this in the future?

Best Regards,
HighPoint Linux Team

Question about HighPoint RocketRAID 642L SCSI driver conflict with Linux AHCI driver

[linux]

Dear Tejun Heo,

  This is HighPoint Linux Team. We found Linux AHCI driver since kernel 3.16
has added ID (0x06421103) to support RocketRAID 642L which is not what we
expected. If we want to load HighPoint RR642L RAID version Linux SCSI
driver, it becomes conflict each other. This affects our customers who need
to use our RAID version driver stack.
  
  Hence,  this is to ask Linux how to solve this conflict with AHCI driver?
and why Linux wants to add RR642L ID (0x06421103) into AHCI driver? Is there
any way to prevent this in the future?

Best Regards,
HighPoint Linux Team

Re: Question about HighPoint RocketRAID 642L SCSI driver conflict with Linux AHCI driver

[Tejun Heo]

Hello,

On Thu, Jun 04, 2015 at 01:05:49PM +0800, linux wrote:
> Dear Tejun Heo,
> 
>   This is HighPoint Linux Team. We found Linux AHCI driver since kernel 3.16
> has added ID (0x06421103) to support RocketRAID 642L which is not what we
> expected. If we want to load HighPoint RR642L RAID version Linux SCSI
> driver, it becomes conflict each other. This affects our customers who need
> to use our RAID version driver stack.
>
>   Hence,  this is to ask Linux how to solve this conflict with AHCI driver?
> and why Linux wants to add RR642L ID (0x06421103) into AHCI driver? Is there
> any way to prevent this in the future?

Hmmm... so, you're trying to load a proprietary driver but you're
having problem because in-kernel ahci attaches to the driver?

* If the driver is built-in, putting the proprietary driver before
  ahci in Makefile will make that driver probe before ahci.

* If module, ahci can be unbound by echoing the PCI bus ID to
  /sys/bus/pci/drivers/ahci/unbind and then bind that to the
  proprietary driver.

* Or you can tell pci-stub driver do grab the PCI ID so that ahci
  doesn't probe it at all.  Once the proprietary driver becomes
  available, the device can be rebound to the driver.

Thanks.

-- 
tejun

Re: Question about HighPoint RocketRAID 642L SCSI driver conflict with Linux AHCI driver

[One Thousand Gnomes]

On Thu, 4 Jun 2015 13:05:49 +0800
"linux" <linux@highpoint-tech.com> wrote:

> Dear Tejun Heo,
> 
>   This is HighPoint Linux Team. We found Linux AHCI driver since kernel 3.16
> has added ID (0x06421103) to support RocketRAID 642L which is not what we
> expected. If we want to load HighPoint RR642L RAID version Linux SCSI
> driver, it becomes conflict each other. This affects our customers who need
> to use our RAID version driver stack.

If your stack existed in full open source form upstream we might be able
to add it the supported raid formats, which would make life even easier
for your customers.

>   Hence,  this is to ask Linux how to solve this conflict with AHCI driver?
> and why Linux wants to add RR642L ID (0x06421103) into AHCI driver? 

So that users can use the hardware with the standard kernel AHCI drivers
because they are best freely available and integrated driver available.

> Is there > any way to prevent this in the future?

Apart from having your customers reconfigure their kernel or carefully
set stuff up at boot time, no.

Alan

Re: Question about HighPoint RocketRAID 642L SCSI driver conflict with Linux AHCI driver

[One Thousand Gnomes]

On Thu, 4 Jun 2015 13:05:49 +0800
"linux" <linux@highpoint-tech.com> wrote:

> Dear Tejun Heo,
> 
>   This is HighPoint Linux Team. We found Linux AHCI driver since kernel 3.16
> has added ID (0x06421103) to support RocketRAID 642L which is not what we
> expected. If we want to load HighPoint RR642L RAID version Linux SCSI
> driver, it becomes conflict each other. This affects our customers who need
> to use our RAID version driver stack.

If your stack existed in full open source form upstream we might be able
to add it the supported raid formats, which would make life even easier
for your customers.

>   Hence,  this is to ask Linux how to solve this conflict with AHCI driver?
> and why Linux wants to add RR642L ID (0x06421103) into AHCI driver? 

So that users can use the hardware with the standard kernel AHCI drivers
because they are best freely available and integrated driver available.

> Is there > any way to prevent this in the future?

Apart from having your customers reconfigure their kernel or carefully
set stuff up at boot time, no.

Alan