[PATCH] drm/hisilicon: Use pcim_enable_device()

[tiantao (H)]

在 2020/12/22 16:27, Daniel Vetter 写道:
> On Tue, Dec 22, 2020 at 1:38 AM tiantao (H) <tiantao6 at huawei.com> wrote:
>>
>> 在 2020/12/22 6:02, Daniel Vetter 写道:
>>> On Mon, Dec 21, 2020 at 08:45:22AM +0800, Tian Tao wrote:
>>>> Using the managed function simplifies the error handling. After
>>>> unloading the driver, the PCI device should now get disabled as
>>>> well.
>>>>
>>>> Signed-off-by: Tian Tao <tiantao6 at hisilicon.com>
>>>> ---
>>>>    drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c | 6 ++----
>>>>    1 file changed, 2 insertions(+), 4 deletions(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c b/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c
>>>> index 02f3bd1..7159018 100644
>>>> --- a/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c
>>>> +++ b/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c
>>>> @@ -329,7 +329,7 @@ static int hibmc_pci_probe(struct pci_dev *pdev,
>>>>       dev->pdev = pdev;
>>>>       pci_set_drvdata(pdev, dev);
>>>>
>>>> -    ret = pci_enable_device(pdev);
>>>> +    ret = pcim_enable_device(pdev);
>>>>       if (ret) {
>>>>               drm_err(dev, "failed to enable pci device: %d\n", ret);
>>>>               goto err_free;
>>>> @@ -338,7 +338,7 @@ static int hibmc_pci_probe(struct pci_dev *pdev,
>>>>       ret = hibmc_load(dev);
>>>>       if (ret) {
>>>>               drm_err(dev, "failed to load hibmc: %d\n", ret);
>>>> -            goto err_disable;
>>>> +            goto err_free;
>>>>       }
>>>>
>>>>       ret = drm_dev_register(dev, 0);
>>>> @@ -354,8 +354,6 @@ static int hibmc_pci_probe(struct pci_dev *pdev,
>>>>
>>>>    err_unload:
>>>>       hibmc_unload(dev);
>>>> -err_disable:
>>>> -    pci_disable_device(pdev);
>>>>    err_free:
>>>>       drm_dev_put(dev);
>>> The drm_dev_put here and in hibmc_pci_remove is wrong, devm_drm_dev_alloc
>>> takes care of that already. I'm kinda suprised you don't have a refcount
>>> underrun already - do you test module unload with KASAN enabled?
>> Thanks for helping to review the code，and kindly giving me advice。
>>
>> this problem have been fixed。
>>
>> c855af2f9c5c60760fd1bed7889a81bc37d2591d drm/hisilicon: Fix use-after-free
> Sorry, I was on an older tree. Note that this fix is incomplete, the
> drm_dev_put in the error path of hibmc_pci_probe still exists.
> -Daniel
I also found the problem, has raised the patch in the internal review 
and testing, to confirm that there is no problem, it will be sent out.
Thanks for the reminder.
>>> The pcim patch looks ok, so Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>
>>>
>>> Cheers, Daniel
>>>
>>>> --
>>>> 2.7.4
>>>>
>