Re: [PATCH] ata: fix a race condition when internal cmd time out

[Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>]

Hello!

On 16.02.2019 6:42, Jason Yan wrote:

> For internal cmds, we will unmap DMA memory associated with the cmd
> before we abort the cmd. If DMA transfering data before the aborting,

    Transferring.

> bus error will occured.

    Occur.

> ata_exec_internal_sg
>    ->ata_port_freeze if timeout
>      ->ata_qc_complete
>        ->ata_sg_clean
>                                        dma transfering data = bus error
>    ->ap->ops->post_internal_cmd
>      ->sas_ata_post_internal
>        ->sas_ata_internal_abort
>          ->abort the cmd
> 
> Fix this by move post_internal_cmd() before unmapping the DMA memory

    Moving.

> when time out. Notice that we have to set ATA_QCFLAG_FAILED flag before
> calling post_internal_cmd() so that the aborting will work.
> 
> Reported-by: luojian <luojian5@huawei.com>
> Signed-off-by: Jason Yan <yanaijie@huawei.com>
[...]

MBR, Sergei