On Wed, Mar 24, 2021 at 09:15:46AM +0000, Gustavo Pimentel wrote:

Hi Greg,

On Tue, Mar 23, 2021 at 13:0:4, Greg Kroah-Hartman 
[off-list ref] wrote:

quoted

On Fri, Feb 12, 2021 at 06:28:03PM +0100, Gustavo Pimentel wrote:

quoted

+static const struct attribute_group xdata_attr_group = {
+	.attrs = default_attrs,
+	.name = DW_XDATA_DRIVER_NAME,
+};

ATTRIBUTE_GROUPS()?

Nicely catched!

quoted

quoted

+static int dw_xdata_pcie_probe(struct pci_dev *pdev,
+			       const struct pci_device_id *pid)
+{
+	const struct dw_xdata_pcie_data *pdata = (void *)pid->driver_data;
+	struct dw_xdata *dw;
+	u64 addr;
+	int err;
+
+	/* Enable PCI device */
+	err = pcim_enable_device(pdev);
+	if (err) {
+		pci_err(pdev, "enabling device failed\n");
+		return err;
+	}
+
+	/* Mapping PCI BAR regions */
+	err = pcim_iomap_regions(pdev, BIT(pdata->rg_bar), pci_name(pdev));
+	if (err) {
+		pci_err(pdev, "xData BAR I/O remapping failed\n");
+		return err;
+	}
+
+	pci_set_master(pdev);
+
+	/* Allocate memory */
+	dw = devm_kzalloc(&pdev->dev, sizeof(*dw), GFP_KERNEL);
+	if (!dw)
+		return -ENOMEM;
+
+	/* Data structure initialization */
+	mutex_init(&dw->mutex);
+
+	dw->rg_region.vaddr = pcim_iomap_table(pdev)[pdata->rg_bar];
+	if (!dw->rg_region.vaddr)
+		return -ENOMEM;
+
+	dw->rg_region.vaddr += pdata->rg_off;
+	dw->rg_region.paddr = pdev->resource[pdata->rg_bar].start;
+	dw->rg_region.paddr += pdata->rg_off;
+	dw->rg_region.sz = pdata->rg_sz;
+
+	dw->max_wr_len = pcie_get_mps(pdev);
+	dw->max_wr_len >>= 2;
+
+	dw->max_rd_len = pcie_get_readrq(pdev);
+	dw->max_rd_len >>= 2;
+
+	dw->pdev = pdev;
+
+	writel(0x0, &(__dw_regs(dw)->RAM_addr));
+	writel(0x0, &(__dw_regs(dw)->RAM_port));
+
+	addr = dw->rg_region.paddr + DW_XDATA_EP_MEM_OFFSET;
+	writel(lower_32_bits(addr), &(__dw_regs(dw)->addr_lsb));
+	writel(upper_32_bits(addr), &(__dw_regs(dw)->addr_msb));
+	pci_dbg(pdev, "xData: target address = 0x%.16llx\n", addr);
+
+	pci_dbg(pdev, "xData: wr_len=%zu, rd_len=%zu\n",
+		dw->max_wr_len * 4, dw->max_rd_len * 4);
+
+	/* Saving data structure reference */
+	pci_set_drvdata(pdev, dw);
+
+	/* Sysfs */
+	err = sysfs_create_group(&pdev->dev.kobj, &xdata_attr_group);

You just raced with userspace and lost :(

Have the driver core properly create/remove your sysfs files, set the
default groups pointer in your driver and all will be fine.

I've gone around and around, searched in other drivers, but I'm not 
understanding your PoV or what I should do. Can you throw me a bone here?
I'm starting to pull my hair off, lol

Set the dev_groups field of the struct device_driver in your pci driver
structure and all should be fine.

But wait, why are you adding attributes to a pci device and not your
"own" device?  You should make a sub-device for this device-specific
things, otherwise it will be impossible to find these types of
attributes anywhere in sysfs.

I would like to ask you about something, it's you the maintainer of misc 
drivers right?

MAINTAINERS shows this so I guess it must be true...

After fixing this issue, does this driver have a chance to be pulled on 
5.13?

No idea, I do not promise anything :)

thanks,

greg k-h