ahci: fix Null pointer dereference in achi_host_active()

commit b29900e6 (AHCI: Make distinct names for ports in /proc/interrupts)
introuded a regression, which resulted Null pointer dereference for achi
host with dummy ports. For ahci ports, when the port is dummy port, its
private_data will be NULL, as ata_dummy_port_ops doesn't support ->port_start.

changes in v2: use pp to check dummy ports, update comments

Reported-and-tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Xiaotian Feng <xtfeng@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Alexander Gordeev <agordeev@redhat.com>
Cc: linux-ide@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
This commit is contained in:
Xiaotian Feng 2013-07-23 11:54:10 +08:00 коммит произвёл Tejun Heo
Родитель bb96961928
Коммит c91bc6ccd1
1 изменённых файлов: 8 добавлений и 1 удалений

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@ -1146,11 +1146,18 @@ int ahci_host_activate(struct ata_host *host, int irq, unsigned int n_msis)
return rc; return rc;
for (i = 0; i < host->n_ports; i++) { for (i = 0; i < host->n_ports; i++) {
const char* desc;
struct ahci_port_priv *pp = host->ports[i]->private_data; struct ahci_port_priv *pp = host->ports[i]->private_data;
/* pp is NULL for dummy ports */
if (pp)
desc = pp->irq_desc;
else
desc = dev_driver_string(host->dev);
rc = devm_request_threaded_irq(host->dev, rc = devm_request_threaded_irq(host->dev,
irq + i, ahci_hw_interrupt, ahci_thread_fn, IRQF_SHARED, irq + i, ahci_hw_interrupt, ahci_thread_fn, IRQF_SHARED,
pp->irq_desc, host->ports[i]); desc, host->ports[i]);
if (rc) if (rc)
goto out_free_irqs; goto out_free_irqs;
} }