Re: [PATCH v7 2/8] PCI/VGA: Deal only with VGA class devices
From: "Maciej W. Rozycki" <macro@orcam.me.uk>
Date: 2023-06-19 03:03:17
Also in:
amd-gfx, dri-devel, intel-gfx, kvm, linux-pci, lkml, nouveau
On Tue, 13 Jun 2023, Sui Jingfeng wrote:
Deal only with the VGA devcie(pdev->class == 0x0300), so replace the
Typo here: s/devcie/device/.
pci_get_subsys() function with pci_get_class(). Filter the non-PCI display device(pdev->class != 0x0300) out. There no need to process the non-display PCI device.
I've only come across this patch series now. Without diving into what this code actually does I have just one question as a matter of interest.
quoted hunk ↗ jump to hunk
diff --git a/drivers/pci/vgaarb.c b/drivers/pci/vgaarb.c index c1bc6c983932..22a505e877dc 100644 --- a/drivers/pci/vgaarb.c +++ b/drivers/pci/vgaarb.c@@ -1500,7 +1496,9 @@ static int pci_notify(struct notifier_block *nb, unsigned long action, struct pci_dev *pdev = to_pci_dev(dev); bool notify = false; - vgaarb_dbg(dev, "%s\n", __func__); + /* Only deal with VGA class devices */ + if (pdev->class != PCI_CLASS_DISPLAY_VGA << 8) + return 0;
Hmm, shouldn't this also handle PCI_CLASS_NOT_DEFINED_VGA? As far as I know it is the equivalent of PCI_CLASS_DISPLAY_VGA for PCI <= 2.0 devices that were implemented before the idea of PCI device classes has developed into its current form. I may have such a VGA device somewhere. Maciej