Re: [PATCH] PCI: Remove redudant calls to pci_create_sysfs_dev_files() and pci_proc_attach_device()
From: Lukas Wunner
Date: Wed Jul 23 2025 - 08:56:10 EST
On Wed, Jul 23, 2025 at 04:41:24PM +0530, Manivannan Sadhasivam wrote:
> Both pci_create_sysfs_dev_files() and pci_proc_attach_device() are called
> from pci_bus_add_device(). Calling these APIs from other places is prone to
> a race condition as nothing prevents the callers from racing against
> each other.
>
> Moreover, the proper place to create SYSFS and PROCFS entries is during
> the 'pci_dev' creation. So there is no real need to call these APIs
> elsewhere.
The raison d'être for the call to pci_create_sysfs_dev_files() in
pci_sysfs_init() is that PCI_ROM_RESOURCEs may appear after device
enumeration but before the late_initcall stage:
https://lore.kernel.org/r/20231019200110.GA1410324@bhelgaas/
Your patch will regress those platforms.
The proper solution is to make the resource files in sysfs static
and call sysfs_update_group() from pci_sysfs_init().
Krzysztof has an old branch where he started working on this:
https://github.com/kwilczynski/linux/commits/kwilczynski/sysfs-static-resource-attributes/
Thanks,
Lukas