On 2012/9/19 13:13, Huang Ying wrote:
> On Wed, 2012-09-19 at 10:40 +0800, Yijing Wang wrote:
>> When we inject aer errors to the target pcie device by aer_inject module, the pci_ops of pci
>> bus which the target device is on will be assigned to pci_ops_aer.So if the target pci device
>> is a bridge, once we hot-remove and hot-add the bridge, the newly created child bus's pci_ops
>> will be assigned to pci_ops_aer too.Now every access to the child bus's devices will result to
>> system panic, because it get a NULL pci_ops in pci_read_aer/pci_write_aer.
>>
>> Signed-off-by: Yijing Wang <wangyijing@xxxxxxxxxx>
>> Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxx>
>> Reviewed-by: Sven Dietrich <Sven.Dietrich@xxxxxxxxxx>
>> ---
>> drivers/pci/pcie/aer/aer_inject.c | 27 ++++++++++++++++++++++++++-
>> 1 files changed, 26 insertions(+), 1 deletions(-)
>>
>> diff --git a/drivers/pci/pcie/aer/aer_inject.c b/drivers/pci/pcie/aer/aer_inject.c
>> index 4e24cb8..0f00a27 100644
>> --- a/drivers/pci/pcie/aer/aer_inject.c
>> +++ b/drivers/pci/pcie/aer/aer_inject.c
>> @@ -109,6 +109,26 @@ static struct aer_error *__find_aer_error_by_dev(struct pci_dev *dev)
>> return __find_aer_error((u16)domain, dev->bus->number, dev->devfn);
>> }
>>
>> +/* find pci_ops of the nearest parent bus */
>> +static struct pci_ops *__find_pci_bus_ops_parent(struct pci_bus *bus)
>> +{
>> + struct pci_bus_ops *bus_ops;
>> + struct pci_bus *pbus = bus->parent;
>> +
>> + if (!pbus)
>> + return NULL;
>> +
>> + while (pbus) {
>> + list_for_each_entry(bus_ops, &pci_bus_ops_list, list)
>> + if (bus_ops->bus == pbus)
>> + return bus_ops->ops;
>> +
>> + pbus = pbus->parent;
>> + }
>> +
>> + return NULL;
>> +}
>> +
>> /* inject_lock must be held before calling */
>> static struct pci_ops *__find_pci_bus_ops(struct pci_bus *bus)
>> {
>> @@ -118,7 +138,9 @@ static struct pci_ops *__find_pci_bus_ops(struct pci_bus *bus)
>> if (bus_ops->bus == bus)
>> return bus_ops->ops;
>> }
>> - return NULL;
>> +
>> + /* can't find bus_ops, fall back to get bus_ops of upstream bus */
>> + return __find_pci_bus_ops_parent(bus);
>> }
>>
>> static struct pci_bus_ops *pci_bus_ops_pop(void)
>> @@ -208,6 +230,7 @@ static int pci_read_aer(struct pci_bus *bus, unsigned int devfn, int where,
>> }
>> out:
>> ops = __find_pci_bus_ops(bus);
>> + BUG_ON(!ops);
>> spin_unlock_irqrestore(&inject_lock, flags);
>> return ops->read(bus, devfn, where, size, val);
>> }
>> @@ -243,6 +266,7 @@ int pci_write_aer(struct pci_bus *bus, unsigned int devfn, int where, int size,
>> }
>> out:
>> ops = __find_pci_bus_ops(bus);
>> + BUG_ON(!ops);
>> spin_unlock_irqrestore(&inject_lock, flags);
>> return ops->write(bus, devfn, where, size, val);
>> }
>> @@ -506,6 +530,7 @@ static struct miscdevice aer_inject_device = {
>> .fops = &aer_inject_fops,
>> };
>>
>> +
>
> unnecessary new line?
>
Yes, it's unnecessary, I will clean this later.
Thanks
Yijing
> Best Regards,
> Huang Ying
>
>> static int __init aer_inject_init(void)
>> {
>> return misc_register(&aer_inject_device);
>
>
>
> .
>
--
Thanks!
Yijing
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
