Re: Suspend to ram regression (2.6.24-rc1-git)

[Jeff Garzik <jeff@garzik.org>]

Jens Axboe wrote:
> On Thu, Nov 01 2007, Jeff Garzik wrote:
>> Jens Axboe wrote:
>>> Reverting just the default AHCI flags makes it work again. IOW, with the
>>> below patch I can suspend properly with current -git.
>>> diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
>>> index ed9b407..77f7631 100644
>>> --- a/drivers/ata/ahci.c
>>> +++ b/drivers/ata/ahci.c
>>> @@ -190,8 +190,7 @@ enum {
>>>   	AHCI_FLAG_COMMON		= ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
>>>  					  ATA_FLAG_MMIO | ATA_FLAG_PIO_DMA |
>>> -					  ATA_FLAG_ACPI_SATA | ATA_FLAG_AN |
>>> -					  ATA_FLAG_IPM,
>>> +					  ATA_FLAG_ACPI_SATA | ATA_FLAG_AN,
>>>  	AHCI_LFLAG_COMMON		= ATA_LFLAG_SKIP_D2H_BSY,
>>
>> sounds like the easy thing to do, in light of this breakage, might be to 
>> default it to off, add a module parameter turning it on by setting that 
>> flag.
> 
> Wouldn't it be better to just get this bug fixed? IOW, is there a reason
> for disabling ALPM if it's Bug Free?
> 
> I'd suggest committing the patch disabling IPM, then Kristen can debug
> the thing in piece in quiet. Once confident it works with ahci again, we
> can revert that commit.

Right -- if you are going to commit a patch "disabling" it, it is best 
to do so via a simple module option, which allows users to easily try 
the feature in parallel with Intel's debugging.

	Jeff