On Friday 27 January 2017 14:26:22 Kalle Valo wrote: > Pali Rohár <pali.rohar@xxxxxxxxx> writes: > > > On Friday 27 January 2017 13:49:03 Kalle Valo wrote: > >> Pali Rohár <pali.rohar@xxxxxxxxx> writes: > >> > >> >> So > >> >> for those other platforms there will be a delay waiting for user-mode > >> >> helper to fail, before trying to get nvs file from /lib/firmware. > >> > > >> > Yes, there will be. But there is no easy way to fix this problem that > >> > kernel is trying to use default/example NVS data... > >> > >> Kernel is doing correctly and requesting NVS data as expected, the > >> problem here is that linux-firmware claims that the example NVS data is > >> real calibration data (which it is not). Distros should not use that, > >> only developers for testing purposes. We should not courage users using > >> example calibration data. > >> > >> The simple fix is to rename the NVS file in linux-firmware to something > >> like wl1251-nvs.bin.example, no need to workaround this in kernel. If > >> you send a patch to linux-firmware I'm happy to ack that. > > > > I agree with rename and fact that default/example data should not be > > used. > > > > But... > > > > 1) Kernel should not read device/model specific data from VFS where > > are stored not-device-specific files preinstalled by linux > > distributions. > > > > And linux distributions are already putting files into VFS and kernel > > cannot enforce userspace to not do that (as they are already doing it). > > I'm having problems to understand what you are saying here. I'm saying that linux distributions are putting files to /lib/firmware which comes from some sources already released. You cannot force linux distributions to stop putting particular file to /lib/firmware *now* after it was already released and recommended. > > 2) It was already tested that example NVS data can be used for N900 e.g. > > for SSH connection. If real correct data are not available it is better > > to use at least those example (and probably log warning message) so user > > can connect via SSH and start investigating where is problem. > > I disagree. Allowing default calibration data to be used can be > unnoticed by user and left her wondering why wifi works so badly. So there are only two options: 1) Disallow it and so these users will have non-working wifi. 2) Allow those data to be used as fallback mechanism. And personally I'm against 1) because it will break wifi support for *all* Nokia N900 devices right now. > > 3) If we do rename *now* we will totally break wifi support on Nokia > > N900. > > Then the distro should fix that when updating the linux-firmware > packages. Can you provide details about the setup, what distro etc? Debian stable, Ubuntu LTSs 14.04, 16.04. And I think that other LTS distributions contains that example nvs file too (I'm not going to verify others, but list will be probably long). Upgrading linux-firmware is against policy of those distributions. So no this is not an solution. -- Pali Rohár pali.rohar@xxxxxxxxx
