Re: [PATCH] libata: warn if speed limited due to 40-wire cable (v2)

[Bill Davidsen <davidsen@tmr.com>]

Stephen Clark wrote:
> Bill Davidsen wrote:
>
>> Alan Cox wrote:
>>  
>>
>>>> it seems broken to manipulate xfer_mask after returning from the 
>>>> driver's ->mode_filter hook.
>>>>
>>>> this patch is more than just a speed-limited warning printk, afaics
>>>>     
>>> I actually suggested that order because the only way the printk can be
>>> done correctly is for it to be the very last test made. Since the mode
>>> filter is not told what mode will be used but just subtracts modes that
>>> are not allowed this should be safe.
>>>   
>>
>> Far better to have a drive which works slowly than one which works 
>> unreliably.
>>
>>  
>>
> That would be true if the 40 wire detection was 100% accurate!
The statement is completely correct, even though the detection may not 
be. ;-)

With the current set(s) of patches to do better detection, cable 
evaluation should be better. But even if not, a slow system is more 
useful than one which doesn't work, crashes because of swap i/o errors, etc.

-- 
bill davidsen <davidsen@tmr.com>
  CTO TMR Associates, Inc
  Doing interesting things with small computers since 1979