* Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>: > On Wed, 18 Mar 2009 16:40:16 -0600 Alex Chiang <achiang@xxxxxx> wrote: > > > A complete re-implementation of fakephp is necessary if it is to > > present its former interface (pre-2.6.27, when it broke). > > We broke an existing interface? wtf? When I introduced physical PCI slots in 2.6.27, one of the changes was that the interface we presented in /sys/bus/pci/slots/ was supposed to represent _physical_ slots only. Before the change, fakephp "abused" that directory by presenting all the PCI devices, independent of any notions of physical slots. No one thought much of changing what fakephp did during review because we thought it was a developer/debug feature only. After the change, instead of presenting a PCI bus address in sysfs, fakephp present something like "fake%d" where %d is the order that we discovered the device. The thought process was that, "this is a debug feature only, so let's make it more obvious". This was an incorrect assumption, it turns out. :( People like embedded were using it for various things, and it was also the only way to remove (and rediscover) PCI devices (if they weren't supported by platform hotplug). You can read the thread here: http://thread.gmane.org/gmane.linux.kernel/761944 The interesting stuff starts in the middle. > If it's been broken for this long then do we actually need to > resurrect it? This entire patch series is about fixing the mess that I helped create. At the time, it was indicated that there was existing software that depended on finding 2.6.26-style (and older) fakephp stuff in /sys/bus/pci/slots/ After some discussion, we thought it would be better for the functionality to live in the new sysfs interfaces I'm introducing in this series. The legacy fakephp stuff is to help transition existing software. Since the only use case of existing software that I know of is in embedded, I think their workaround was to not move to 2.6.27. > If so, do we need to resurrect it in its old form? This would appear > to be an opportunity to improve that interface, unless the old one > was perfect? Well, the goal is to get people away from fakephp completely and move them to these new interfaces. The legacy fakephp stuff is just a transition aid. Thanks. /ac -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
