Re: [PATCH] sata_sil: ignore and clear spurious IRQs while executing commands by polling

[Jeff Garzik <jeff@garzik.org>]

Tejun Heo wrote:
> sata_sil used to trigger HSM error if IRQ occurs during polling
> command.  This didn't matter because polling wasn't used in sata_sil.
> However, as of 2.6.20, all IDENTIFYs are performed by polling and
> device detection sometimes fails due to spurious IRQ.  This patch
> makes sata_sil ignore and clear spurious IRQ while executing commands
> by polling.
> 
> Signed-off-by: Tejun Heo <htejun@gmail.com>
> ---
> This fixes bug#7996 and IMHO should also be included in -stable.
> Thanks.
> 
> diff --git a/drivers/ata/sata_sil.c b/drivers/ata/sata_sil.c
> index 1487255..aaff357 100644
> --- a/drivers/ata/sata_sil.c
> +++ b/drivers/ata/sata_sil.c
> @@ -386,9 +386,15 @@ static void sil_host_intr(struct ata_port *ap, u32 bmdma2)
>  		goto freeze;
>  	}
>  
> -	if (unlikely(!qc || qc->tf.ctl & ATA_NIEN))
> +	if (unlikely(!qc))
>  		goto freeze;
>  
> +	if (unlikely(qc->tf.flags & ATA_TFLAG_POLLING)) {
> +		/* this sometimes happens, just clear IRQ */
> +		ata_chk_status(ap);
> +		return;

applied