Re: [patch 09/15] libata: Improved ata_exec_internal timeout handling

[Tejun Heo <htejun@gmail.com>]

brking@us.ibm.com wrote:
> Currently ata_exec_internal does very minimal cleanup if
> the executing command times out. This works for most usage
> scenarios, but can cause problems for hosts that set
> ATA_FLAG_PIO_DMA. For these users, the DMA buffer gets unmapped
> while the timed out out command is still active, which has
> the potential to cause PCI DMA errors if the command is
> still in progress. The following patch modifies ata_exec_internal
> to invoke eng_timeout on a timeout to allow for the timed out
> command to be cleaned up better before proceeding further.
> This patch is also in preparation for SAS attached SATA devices.
> 

Hello, again.

ata_exec_internal() will be used during EH, so if you call error handler
from ata_exec_internal()....  In my pending EH patchset, there's a patch
to implement ->post_internal() callback which cleans up after an
internal command (successful or not).  Hopefully, it will be merged in
not too distant future.  Can ata_exec_internal() timeout handling wait
till then?

-- 
tejun