Bastien Nocera writes: > On Fri, 2010-01-29 at 19:46 -0500, Michael Poole wrote: >> > [1]: Comments on the patch at >> > http://thread.gmane.org/gmane.linux.bluez.kernel/4279 would be >> > appreciated >> >> This patch does not work for me. Before, the first time after each >> boot >> that I tried to connect to an Apple Magic Mouse, it failed with -14 >> (EFAULT). With this patch, it fails with -22 (EINVAL) instead. The >> -EFAULT *was* due to hidp_parse()'s copy_from_user(). I have not >> looked >> yet to see where the -EINVAL is coming from -- would that help? (Both >> with and without your patch, the second attempt to connect works.) > > I don't get -EFAULT anymore (it was failing to copy the rd_data from > user-space), but I do get -EINVALs now. I haven't investigated it > though. My guess is that the hid parser fails. > > Could you compare the sizes of the data gathered in user-space? The bug mysteriously disappeared when I tried to apply kgdb to the problem. Your patch won't do the trick because the hidp_connadd_req structure has also gone out of scope by the time the hid-(whatever) probe function is called. The ioctl has returned to the user, but the new hid-(whatever) module is not yet loaded. That is, the sequence looks like this: - Application triggers hidp_sock_ioctl(socket, HIDPCONNADD, &connadd). - This starts the connection, and returns 0... - ... but also indicates that some other module needs to be loaded. - User-space loads the appropriate module does init_module()... - which calls the module_init() function... - which calls hid_register_driver()... - which eventually attaches the new driver to the device... - triggering the module's probe() function to call hid_parse()... - hid_parse() fails because its hidp_connadd_req is gone. Marcel, I think this is a case where the subsystem maintainer should make the call on how to fix it. I can write and locally test a patch, but I don't want to assume that (for example) the desired solution is to keep a copy of the Report descriptor in the hidp_session. The USB HID core sends a GET_DESCRIPTOR request for the Report descriptor, which isn't practical here because that descriptor is only available through SDP. Michael Poole -- To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
