Hi David, On Fri, Feb 15, 2013, David Herrmann wrote: > On Fri, Feb 15, 2013 at 12:29 PM, Kirill A. Shutemov > <kirill.shutemov@xxxxxxxxxxxxxxx> wrote: > > Hi David and all, > > > > There's claim in uhid.h that the interface is "compatible even between > > architectures". But it obviously is not true: struct uhid_create_req > > contains pointer which breaks everything. > > > > The easy way to demonstrate the issue is compile uhid-example.c with -m32 > > and try to run it on 64 bit kernel. Creating of the device will fail. > > Indeed, we missed that. We should probably also notify the HIDP > developers as "struct hidp_connadd_req" suffers from the same > problems. (CC'ed) > > > I don't see an easy way to fix this. Few options: > > > > 1. Replace the pointer with u64. It will fix the issue, but it breaks ABI > > which is never a good idea. Not sure how many users interface already > > has. > > The only users I am aware of is an HID debugging tool and experimental > HoG Bluetooth support (bluez). Maybe Marcel or Johan can comment > whether this is already used by bluez-5? If it is, then we shouldn't > break ABI and go with #2+#3. Otherwise, I think changing to u64 should > be ok. > On the other hand, it would break any future build for older stable > kernels so not breaking ABI is probably the best idea. Any comments? I > can add a COMPAT fix and a comment to fix this in the next version of > UHID_CREATE. The HoG code in BlueZ 5 does indeed use this API and it's also not anymore behind any kind of experimental flag (i.e. it is an officially supported feature). Johan -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
