On Wed, 2019-01-30 at 14:21 +0000, bugzilla-daemon@xxxxxxxxxxxxxxxxxxx wrote: > https://bugzilla.kernel.org/show_bug.cgi?id=201609 > > Bjorn Helgaas (bhelgaas@xxxxxxxxxx) changed: > > What |Removed |Added > ------------------------------------------------------------------- > --------- > CC| |bhelgaas@xxxxxxxxxx > > --- Comment #7 from Bjorn Helgaas (bhelgaas@xxxxxxxxxx) --- > I don't know what the sysfs namespace rules are (if there are > any). It doesn't sound ideal for the PCI core to prefix all the > files in a PCI device directory with "pci_" or similar, since we > already know by the path (/sys/devices/pci0000:00, > /sys/bus/pci/devices, etc) that they are PCI-related). In the early days, we all simply grabbed files in the directory. This resulted in a complete lack of namespacing for everything. Arguably this was the really silly thing to do but we stuck with it. What it means is that now we have to be very careful about adding files because things like this can easily happen. In particular, if you add a generic name like "revision" there's a really good chance some driver already has it. THere's nothing we can do about the prior lack of namespacing, but if you don't want to check every driver in the kernel, using a namespace prefix is a good way of avoiding clashes like this. You can still add a non-namespaced file, it's just you're on the hook to check every driver to prevent cockups like this. The key point is that if the file you clashed with is in use by userspace, we can't rename it because it's an ABI, so now the conflict is unresolvable. I don't think this applies in the aic driver, but it's the reason why you need to be very careful about adding files. James
