Re: [PATCH v2 7/7] cxl/memdev: Register for and process CPER events

From: Ira Weiny
Date: Tue Dec 12 2023 - 19:18:19 EST


Dan Williams wrote:
> Ira Weiny wrote:

[snip]

> > diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
> > index e5d770e26e02..7a891b4641cc 100644
> > --- a/drivers/cxl/cxlmem.h
> > +++ b/drivers/cxl/cxlmem.h
> > @@ -481,6 +481,8 @@ struct cxl_memdev_state {
> > struct cxl_security_state security;
> > struct cxl_fw_state fw;
> >
> > + struct notifier_block cxl_cper_nb;

delete this...


[snip]

> >
> > +#define CXL_EVENT_HDR_FLAGS_REC_SEVERITY GENMASK(1, 0)
> > +static void cxl_cper_event_call(struct cxl_cper_event_data *ev_data)
> > +{
> > + struct cper_cxl_event_devid *device_id = &ev_data->rec->hdr.device_id;
> > + struct cxl_dev_state *cxlds = NULL;
> > + enum cxl_event_log_type log_type;
> > + struct pci_dev *pdev;
> > + unsigned int devfn;
> > + u32 hdr_flags;
> > +
> > + devfn = PCI_DEVFN(device_id->device_num, device_id->func_num);
> > + pdev = pci_get_domain_bus_and_slot(device_id->segment_num,
> > + device_id->bus_num, devfn);
>
> What if pci_get_domain_bus_and_slot() returned NULL?

:-/ yep.

>
> > +
> > + guard(mutex)(&pdev->dev.mutex);
>
> Lets not open code this since device_lock() is so prevalent it deserves
> its own guard() type:
>
> DEFINE_GUARD(device, struct device *, device_lock(_T), device_unlock(_T))

Good idea.

>
> > + if (pdev->driver == &cxl_pci_driver)
> > + cxlds = pci_get_drvdata(pdev);
> > + if (!cxlds)
> > + goto out;
>
> Lets not mix usage of cleanup.h helpers with usage of goto. The helpers
> are there to eliminate goto errors. Just add a new helper:
>
> DEFINE_FREE(pci_dev_put, struct pci_dev *, if (_T) pci_dev_put(_T))
>
> ...and declare @pdev as:
>
> struct pci_dev *pdev __free(pci_dev_put) = NULL;
>

Even better idea. Done.

Thanks,
Ira