On Fri, Aug 17, 2012 at 02:39:34PM -0600, Bjorn Helgaas wrote: > On Fri, Aug 17, 2012 at 2:07 PM, Thierry Reding > <thierry.reding@xxxxxxxxxxxxxxxxx> wrote: > > On Fri, Aug 17, 2012 at 01:32:45PM -0600, Bjorn Helgaas wrote: > >> On Fri, Aug 17, 2012 at 12:29 PM, Thierry Reding > >> <thierry.reding@xxxxxxxxxxxxxxxxx> wrote: > >> > On Fri, Aug 17, 2012 at 11:44:31AM -0600, Bjorn Helgaas wrote: > >> >> On Fri, Aug 17, 2012 at 11:36 AM, David Daney <ddaney.cavm@xxxxxxxxx> wrote: > >> >> > For MIPS, Thierry Reding's patch in linux-next (PCI: Keep pci_fixup_irqs() > >> >> > around after init) causes: > >> >> > > >> >> > WARNING: vmlinux.o(.text+0x22c784): Section mismatch in reference from the > >> >> > function pci_fixup_irqs() to the function .init.text:pcibios_update_irq() > >> >> > > >> >> > The MIPS implementation of pcibios_update_irq() is __init, so there is > >> >> > conflict with the removal of __init from pci_fixup_irqs() and > >> >> > pdev_fixup_irq(). > >> >> > > >> >> > Can you guys either remove the patch from linux-next, or improve it to also > >> >> > fix up any architecture implementations of pdev_update_irq()? > >> >> > >> >> Crap, there are lots of arches with this issue. I'll fix it up. > >> >> Thanks for pointing it out! > >> > > >> > Oh wow... looks like I've opened a can of worms there. This requires > >> > quite a lot of other functions to have their annotations removed as > >> > well. Bjorn, how do you want to handle this? > >> > >> David said "pdev_update_irq()," but I think he meant "pcibios_update_irq()." > >> > >> Almost all the pcibios_update_irq() implementations are identical, so > >> I think I'll just supply a weak implementation and remove the > >> redundant arch versions. > > > > That makes sense. However I've just tested a build with section mismatch > > debugging enabled on ARM and there are a few more that need __init or > > __devinit removed to get rid of the warnings: > > > > pci_common_init() > > pcibios_init_hw() > > pcibios_init_resources() > > pcibios_swizzle() > > pcibios_update_irq() > > > > pci_scan_root_bus() also needs __devinit removed. I haven't checked the > > other architectures because I'll have to build cross-compilers for them > > first, but I suspect most of them will have a similar list. I'm not sure > > how well this kind of change is going to go down with the respective > > architecture maintainers, though. > > Hmm, yeah, this is a mess, isn't it? Just about everything in PCI > will need __devinit removed. We've been assuming that the only way > for things to show up after init is via hotplug. But you're breaking > that assumption by doing *all* enumeration after init. There are > approximately a bajillion __init and __devinit annotations just in > drivers/pci, not to mention those in the architectures. > > Well, maybe you just need to turn on CONFIG_HOTPLUG. How would that > affect you? I think we would still have to change some __inits to > __devinit, including pcibios_update_irq(), but it might be more > manageable. You said that depending on HOTPLUG wouldn't be enough because it would exclude reenumeration at runtime if HOTPLUG wasn't defined. Also it is theoretically possible to build a kernel without HOTPLUG but have the enumeration start after init because of deferred probing. Those cases won't work if we keep __init or __devinit respectively, right? > I started working on this, but it sounds like you're in a better > position to find problems and test fixes, so how about if I just let > you handle it? :) I won't be able to test anything beyond Tegra because I'm lacking the hardware. But with the section mismatch debugging enabled all issues should be detected at compile time anyway, so it's just a problem of getting cross-compilers for all architectures that support PCI. Thierry
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