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

[Jason Yan]

Hi, Sergei

Thanks for the review.

On 2019/2/16 15:45, Sergei Shtylyov wrote:
> 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,
>
>  ÂÂ Transferring.
>
> > bus error will occured.
>
>  ÂÂ Occur.
>
> > ata_exec_internal_sg
> > ÂÂ ->ata_port_freeze if timeout
> > ÂÂÂÂ ->ata_qc_complete
> > ÂÂÂÂÂÂ ->ata_sg_clean
> > ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ dma transfering data = bus error
> > ÂÂ ->ap->ops->post_internal_cmd
> > ÂÂÂÂ ->sas_ata_post_internal
> > ÂÂÂÂÂÂ ->sas_ata_internal_abort
> > ÂÂÂÂÂÂÂÂ ->abort the cmd
> >
> > Fix this by move post_internal_cmd() before unmapping the DMA memory
>
>  ÂÂ 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@xxxxxxxxxx>
> > Signed-off-by: Jason Yan <yanaijie@xxxxxxxxxx>
> [...]
>
> MBR, Sergei