linux-kernel - Re: Hack to fix not working spindown over Firewire

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 30 Apr 2008 15:36:36 +0200
From:	Stefan Richter <stefanr@...6.in-berlin.de>
To:	linux-kernel@...r.kernel.org, linux-scsi@...r.kernel.org
Subject: Re: Hack to fix not working spindown over Firewire

I wrote:
> Tino Keitel wrote:
>> @@ -1788,8 +1788,16 @@ static int sd_start_stop_device(struct scsi_disk *sdkp, int start)
>>  	struct scsi_device *sdp = sdkp->device;
>>  	int res;
>>  
>> -	if (start)
>> +	if (start) {
>>  		cmd[4] |= 1;	/* START */
>> +		if(!strncmp(sdp->vendor, "WDC WD32", 8)) {
>> +			cmd[4] |= (1 << 4); /* power condition */
>> +		}
>> +	} else {
>> +		if(!strncmp(sdp->vendor, "WDC WD32", 8)) {
>> +			cmd[4] |= (2 << 4); /* power condition */
>> +		}
>> +	}
>>  
>>  	if (!scsi_device_online(sdp))
>>  		return -ENODEV;
> 
[...]
> The traditional way to handle things like this is:
> 
>    - Implement this as a workaround in sd.
> 
>    - Make this workaround conditional on a quirks flag in
>      struct scsi_device.
> 
>    - Switch this flag on in a place where it can be reliably
>      detected that this device needs it.  There is an interface
>      to do this in userspace.  But in this particular case, the
>      best place is the sbp2 driver (ond firewire-sbp2 driver),
>      because it can detect PL-3507 firmwares by means of firmware
>      identifiers.
[...]
> On the other hand, perhaps we can enable the workaround unconditional
> for all firewire disks (switch in the flag in sbp2 and firewire-sbp2
> without looking at the device) or for all RBC disks (switch on the flag
> in sd.c if sdev->type == TYPE_RBC).

PS:
If it works for all RBC devices (it should according to the spec...) &&
your ICY Box exposes itself as RBC device (it should do so), then we
don't need any changes to struct scsi_device and to sbp2/ firewire-sbp2.
-- 
Stefan Richter
-=====-==--- -=-- ====-
http://arcgraph.de/sr/
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/