On Mon, 2024-08-19 at 21:28 +0300, Andy Shevchenko wrote:

On Mon, Aug 19, 2024 at 06:51:47PM +0200, Philipp Stanner wrote:

quoted

stmicro uses PCI devres in the wrong way. Resources requested
through pcim_* functions don't need to be cleaned up manually in
the
remove() callback or in the error unwind path of a probe()
function.

Moreover, there is an unnecessary loop which only requests and
ioremaps
BAR 0, but iterates over all BARs nevertheless.

Furthermore, pcim_iomap_regions() and pcim_iomap_table() have been
deprecated by the PCI subsystem in commit e354bb84a4c1 ("PCI:
Deprecate
pcim_iomap_table(), pcim_iomap_regions_request_all()").

Replace these functions with pcim_iomap_region().

Remove the unnecessary manual pcim_* cleanup calls.

Remove the unnecessary loop over all BARs.

...

loongson_dwmac_probe()

quoted

+	memset(&res, 0, sizeof(res));
+	res.addr = pcim_iomap_region(pdev, 0, pci_name(pdev));
+	if (IS_ERR(res.addr)) {
+		ret = PTR_ERR(res.addr);
+		goto err_disable_device;

It seems your series reveals issues in the error paths of .probe():s
in many drivers...

If we use pcim variant to enable device, why do we need to explicitly
disable it?

No.

quoted

 	}

...

loongson_dwmac_remove()

quoted

 	pci_disable_msi(pdev);
 	pci_disable_device(pdev);

Not sure why we need these either...

It's complicated.

The code uses pciM_enable_device(), but here in remove
pci_disable_device().

pcim_enable_device() sets up a disable callback which only calls
pci_disable_device() if pcim_pin_device() has not been called.

This code doesn't seem to call pcim_pin_device(), so I think
pci_disable_device() could be removed.


I definitely would not feel confident touching pci_disable_msi(),
though. The AFAIK biggest problem remaining in PCI devres is that the
MSI code base implicitly calls into devres, see here [1]


P.


[1] https://lore.kernel.org/all/ee44ea7ac760e73edad3f20b30b4d2fff66c1a85.camel@redhat.com/ (local)