On Fri, Mar 17, 2017 at 05:26:18PM +0100, Luis R. Rodriguez wrote: > On Fri, Mar 17, 2017 at 10:43:39AM +0000, Liviu Dudau wrote: > > On Fri, Mar 17, 2017 at 01:33:21AM +0100, Luis R. Rodriguez wrote: > > > a) should we then use a Fixes tag for this patch ? > > > > I'm not aware of issues being reported, but Lorenzo might have more info on this. > > Lorenzo ? If not what exactly made you discover this ? If it is a fix, and only > ARM64 is implicated, seems like a worthy change to consider for stable for the > sake of stable ARM64 kernels. But, that would leave the PCI config space without > a simple 1 liner fix too -- so maybe its not worth it. Distributions wanting > to support ARM64 however would like to carry these changes, so some annotations > such as Fixes should help. It started with this thread: http://lists.infradead.org/pipermail/linux-arm-kernel/2017-January/477353.html this series is not fixing any current issue I am aware of (but I am not keen on leaving code as-is either) hence adding a Fixes: tag is problematic. I would leave stable kernels alone for the time being. Lorenzo > > > b) it does not seem clear what the semantics for pgprot_device() or even > > > pgprot_noncached(). Can you add some ? > > > > > > 8b921acfeffdb ("PCI: Add pci_remap_iospace() to map bus I/O resources") > > > > > > Also this patch claims archs can override this call alone, as its __weak. > > > So is the right thing to do to change pci_remap_iospace() to pgprot_noncached() > > > or is it for archs to add their own pci_remap_iospace()? If so why ? Without > > > proper semantics defined for these helpers this is all fuzzy. > > > > That was the initial intention, to let arches / platforms overwrite the whole > > pci_remap_iospace(). I guess the reality is that no one needs to overwrite it except > > for the AArch64 quirk, so probably easier to remove the __weak and fix the attributes for arm64. > > Sounds much more reasonable to me. > > Luis
