Re: MWDMA Issue: sda: unknown partition table

[viresh kumar <viresh.kumar@st.com>]

Tejun,

On 01/21/2011 10:09 PM, Tejun Heo wrote:
>> > As suggested by you earlier, i am doing following on card insertion and removal,
>> > after resetting card through controller.
>> > 
>> > 		ata_ehi_hotplugged(ehi);
>> > 		ata_port_freeze(ap);
>> > 
>> > and after that only i get that error message through following path:
>> > Kthread()->scsi_error_handler()->ata_scsi_error()->ata_bmdma_error_handler()
>> > ->ata_sff_error_handler()->ata_do_eh()
> Hmmm... okay, so that's from the hotplugging.
> 
>> > I tried again, but couldn't find why i am getting these two issues:
>> > 	ata1: exception Emask 0x10 SAct 0x0 SErr 0x0 action 0xe frozen
> Yeah, it should be possible to avoid the above if it's coming from
> hotplug.  Identify where and why AC_ERR_ATA_BUS is being set and work
> around it.  There's no reason for it to be set after a hotplug anyway.
> 

I debugged it further, ehi->err_mask |= AC_ERR_ATA_BUS is done in
ata_ehi_hotplugged(). I tried to find the place where it should be cleared in
code path, but couldn't find it.

Further i checked the order in which code is executed and taken dump of that:
ata_ehi_hotplugged, ata_port_freeze, ata_port_abort, ata_do_link_abort,
ata_port_schedule_eh, scsi_schedule_eh.

And just after this following error was printed:
ata1: exception Emask 0x10 SAct 0x0 SErr 0x0 action 0xe frozen

I feel ata_port_schedule_eh() shouldn't have been called. It is called because
there were no qc's in ata_port.

--
viresh