Hi Manivannan,
> From: Manivannan Sadhasivam, Sent: Wednesday, June 22, 2022 5:49 PM
>
> On Wed, Jun 22, 2022 at 11:50:31AM +0900, Yoshihiro Shimoda wrote:
> > Add pci_epc_release() for epc->dev.release and move kfree(epc)
> > to the release function. Otherwise, WARN() happened when a PCIe
> > endpoint driver is removed.
>
> So you have mentioned why you are adding the release callback but not justified
> the move of kfree() to release callback.
>
> The commit message should clearly state what the patch does and why.
>
> You can use something like below:
>
> Since there is no release callback defined for the PCI EPC device, the below
> warning is thrown by driver core when a PCI endpoint driver is removed:
>
> Device 'e65d0000.pcie-ep' does not have a release() function, it is broken and must be fixed. See
> Documentation/core-api/kobject.rst.
> WARNING: CPU: 0 PID: 139 at drivers/base/core.c:2232 device_release+0x78/0x8c
>
> Hence, add the release callback and also move the kfree(epc) from
> pci_epc_destroy() so that the epc memory is freed when all references are
> dropped.
Thank you for your suggestion! This description looks the best to me.
> >
> > Device 'e65d0000.pcie-ep' does not have a release() function, it is broken and must be fixed. See
> Documentation/core-api/kobject.rst.
> > WARNING: CPU: 0 PID: 139 at drivers/base/core.c:2232 device_release+0x78/0x8c
> >
> > Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
>
> With the commit message fixed,
>
> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
Thank you!
Best regards,
Yoshihiro Shimoda
> Thanks,
> Mani
>
> > ---
> > Changes from v1:
> > - Move kfree(epc) to the release function.
> > - Revised the commit description.
> >
> >
> > drivers/pci/endpoint/pci-epc-core.c | 7 ++++++-
> > 1 file changed, 6 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
> > index 3bc9273d0a08..2542196e8c3d 100644
> > --- a/drivers/pci/endpoint/pci-epc-core.c
> > +++ b/drivers/pci/endpoint/pci-epc-core.c
> > @@ -724,7 +724,6 @@ void pci_epc_destroy(struct pci_epc *epc)
> > {
> > pci_ep_cfs_remove_epc_group(epc->group);
> > device_unregister(&epc->dev);
> > - kfree(epc);
> > }
> > EXPORT_SYMBOL_GPL(pci_epc_destroy);
> >
> > @@ -746,6 +745,11 @@ void devm_pci_epc_destroy(struct device *dev, struct pci_epc *epc)
> > }
> > EXPORT_SYMBOL_GPL(devm_pci_epc_destroy);
> >
> > +static void pci_epc_release(struct device *dev)
> > +{
> > + kfree(to_pci_epc(dev));
> > +}
> > +
> > /**
> > * __pci_epc_create() - create a new endpoint controller (EPC) device
> > * @dev: device that is creating the new EPC
> > @@ -779,6 +783,7 @@ __pci_epc_create(struct device *dev, const struct pci_epc_ops *ops,
> > device_initialize(&epc->dev);
> > epc->dev.class = pci_epc_class;
> > epc->dev.parent = dev;
> > + epc->dev.release = pci_epc_release;
> > epc->ops = ops;
> >
> > ret = dev_set_name(&epc->dev, "%s", dev_name(dev));
> > --
> > 2.25.1
> >
>
> --
> மணிவண்ணன் சதாசிவம்
