On 07/15/2010 11:20 AM, Tejun Heo wrote:
> Hmm... it looks like SStatus and SControl are swapped here. Maybe
> there's a race condition in SIDPR code. I'll look into it a bit more.
So, something like this. Can you please apply the patch and see
whether the problem goes away?
Thanks.
--
tejun
diff --git a/drivers/ata/ata_piix.c b/drivers/ata/ata_piix.c
index 7409f98..3971bc0 100644
--- a/drivers/ata/ata_piix.c
+++ b/drivers/ata/ata_piix.c
@@ -158,6 +158,7 @@ struct piix_map_db {
struct piix_host_priv {
const int *map;
u32 saved_iocfg;
+ spinlock_t sidpr_lock; /* FIXME: remove once locking in EH is fixed */
void __iomem *sidpr;
};
@@ -951,12 +952,15 @@ static int piix_sidpr_scr_read(struct ata_link *link,
unsigned int reg, u32 *val)
{
struct piix_host_priv *hpriv = link->ap->host->private_data;
+ unsigned long flags;
if (reg >= ARRAY_SIZE(piix_sidx_map))
return -EINVAL;
+ spin_lock_irqsave(&hpriv->sidpr_lock, flags);
piix_sidpr_sel(link, reg);
*val = ioread32(hpriv->sidpr + PIIX_SIDPR_DATA);
+ spin_unlock_irqrestore(&hpriv->sidpr_lock, flags);
return 0;
}
@@ -964,12 +968,15 @@ static int piix_sidpr_scr_write(struct ata_link *link,
unsigned int reg, u32 val)
{
struct piix_host_priv *hpriv = link->ap->host->private_data;
+ unsigned long flags;
if (reg >= ARRAY_SIZE(piix_sidx_map))
return -EINVAL;
+ spin_lock_irqsave(&hpriv->sidpr_lock, flags);
piix_sidpr_sel(link, reg);
iowrite32(val, hpriv->sidpr + PIIX_SIDPR_DATA);
+ spin_unlock_irqrestore(&hpriv->sidpr_lock, flags);
return 0;
}
@@ -1566,6 +1573,7 @@ static int __devinit piix_init_one(struct pci_dev *pdev,
hpriv = devm_kzalloc(dev, sizeof(*hpriv), GFP_KERNEL);
if (!hpriv)
return -ENOMEM;
+ spin_lock_init(&hpriv->sidpr_lock);
/* Save IOCFG, this will be used for cable detection, quirk
* detection and restoration on detach. This is necessary
