Re: [PATCH -next] tty: moxa: add missing pci_disable_device()

[Ruan Jinjie]

On 2022/9/23 19:25, Greg KH wrote:
> On Fri, Sep 23, 2022 at 06:12:03PM +0800, Ruan Jinjie wrote:
>>
>>
>> On 2022/9/23 17:56, Greg KH wrote:
>>> On Fri, Sep 23, 2022 at 05:25:30PM +0800, ruanjinjie wrote:
>>>> Driver should call pci_disable_device() if it returns from
>>>> moxa_pci_probe() with error.
>>>
>>> Why?
>>>
>>> That is not a normal thing to do, as you can disable other PCI devices
>>> attached to it, right?
>>>
>>>> Meanwhile, the driver calls pci_enable_device() in
>>>> moxa_pci_probe(), but never calls pci_disable_device() during removal.
>>>
>>> And is that really a problem?
>>>
>>>>
>>>> Signed-off-by: ruanjinjie <ruanjinjie@xxxxxxxxxx>
>>>> ---
>>>>  drivers/tty/moxa.c | 4 +++-
>>>>  1 file changed, 3 insertions(+), 1 deletion(-)
>>>
>>> Do you have this hardware to test with?
>>>
>>> How did you find this issue?
>>>
>>
>> We use static analysis via coccinelle to find the above issue. The
>> command we use is below:
>>
>> spatch -I include -timeout 60 -very_quiet -sp_file
>> pci_disable_device_missing.cocci drivers/tty/moxa.c
> 
> Please test with real hardware and look up what pci_disable_device()
> does.

Thank you very much for your sincere advice! we will deeply experiment
with this issue.

> 
> greg k-h