On 3/1/2018 11:37 PM, Hans de Goede wrote:
Hi,

On 01-03-18 20:54, Arend van Spriel wrote:
On 3/1/2018 9:35 AM, Hans de Goede wrote:
HI,

On 28-02-18 20:43, Arend van Spriel wrote:
On 2/28/2018 3:52 PM, Hans de Goede wrote:
Hi,

On 27-02-18 00:04, Arend van Spriel wrote:
On 2/26/2018 12:22 PM, Hans de Goede wrote:
Hi,

On 26-02-18 12:01, Arend van Spriel wrote:
On 2/26/2018 11:29 AM, Hans de Goede wrote:
Hi,

On 26-02-18 11:22, Arend van Spriel wrote:
On 2/25/2018 3:52 PM, Hans de Goede wrote:
Hi,

On 26-05-17 12:57, Hans de Goede wrote:
The firmware responding with -EBUSY when trying to add an extra
virtual-if
is a normal thing, do not print an error for this.

Signed-off-by: Hans de Goede <hdego...@redhat.com>

I'm now seeing this on another device too, but this time the
error
thrown is -EBADE, this seems to be new with recent kernels:

Yup. Before we were passing firmware errors up to user-space,
which
was confusing and potentially be misinterpreted. However,
looking at
the output below it would have been good to log the firmware
error as
well. And staring at it some more I suddenly realize I broke the
feature detection module with this change. Actually only the
GSCAN
feature detection.

[root@localhost ~]# dmesg | grep brcmfmac
[   34.265950] usbcore: registered new interface driver brcmfmac
[   34.266059] brcmfmac 0000:01:00.0: enabling device (0000 ->
0002)
[   34.376468] brcmfmac: brcmf_fw_map_chip_to_name: using
brcm/brcmfmac4356-pcie.bin for chip 0x004356(17238) rev 0x000002
[   34.855143] brcmfmac 0000:01:00.0: Direct firmware load for
brcm/brcmfmac4356-pcie.clm_blob failed with error -2
[   34.855147] brcmfmac: brcmf_c_process_clm_blob: no clm_blob
available(err=-2), device may have limited channels available
[   34.857029] brcmfmac: brcmf_c_preinit_dcmds: Firmware
version =
wl0:
Jun  4 2017 16:50:07 version 7.35.101.6 (r702795) FWID
01-5e8eb735
[   34.938854] brcmfmac 0000:01:00.0 wlp1s0: renamed from wlan0
[   37.086420] brcmfmac: brcmf_p2p_create_p2pdev: set p2p_disc
error
[   37.086431] brcmfmac: brcmf_cfg80211_add_iface: add iface
p2p-dev-wlp1s0 type 10 failed: err=-52

[root@localhost ~]# strings
/lib/firmware/brcm/brcmfmac4356-pcie.bin |
tail -n 1
4356a2-roml/pcie-ag-msgbuf-splitrx-p2p-pno-aoe-pktfilter-keepalive-sr-mchan-pktctx-proptxstatus-ampduhostreorder-lpc-pwropt-txbf-wl11u-mfp-tdls-amsdutx-sarctrl-proxd-hs20sta-rcc-wepso-ndoe-linkstat-gscan-hchk-logtrace-roamexp-rmon





Version: 7.35.101.6 (r702795) CRC: 4f3f65c5 Date: Sun 2017-06-04
16:51:38 PDT Ucode Ver: 963.316 FWID: 01-5e8eb735

It would be good if we can silence these errors, or maybe at a
minimum lower their log-level from error to warning?

I had a look at it and it seems to be a difference in firmware
api
that we need to support in the driver. Need to do a bit more
digging,
but it seems an actual issue. You could silence it for now, but I
prefer to wait for the fix.

Ok, what is the ETA of a fix for this?

Actually went back to an old log you sent and noticed:

[   15.714569] brcmfmac: brcmf_attach Enter
[   15.714756] brcmfmac: brcmf_fweh_register event handler
registered
for PSM_WATCHDOG
[   15.714757] brcmfmac: brcmf_proto_attach Enter
[   15.716598] brcmfmac: brcmf_bus_started
[   15.716603] brcmfmac: brcmf_add_if Enter, bsscfgidx=0, ifidx=0
[   15.716604] brcmfmac: brcmf_add_if allocate netdev interface
[   15.716622] brcmfmac: brcmf_add_if  ==== pid:2a, if:wlan%d
(00:00:00:00:00:00) created ===
[   15.716624] brcmfmac: brcmf_bus_change_state 0 -> 1
[   15.717841] brcmfmac: brcmf_fil_iovar_data_get ifidx=0,
name=cur_etheraddr, len=6
[   15.717843] brcmutil: data
[   15.717847] 00000000: 44 2c 05 9e c9 02   D,....

So mac address of the device is 44:2c:05:9e:c9. However, further
down
I see:

[   17.819113] brcmfmac: brcmf_netdev_set_mac_address Enter,
bsscfgidx=0
[   17.819122] brcmfmac: brcmf_fil_iovar_data_set ifidx=0,
name=cur_etheraddr, len=6
[   17.819127] brcmutil: data
[   17.819135] 00000000: aa 3e 81 77 bc 40   .>.w.@
[   17.819864] brcmfmac: brcmf_netdev_set_mac_address updated to
aa:3e:81:77:bc:40

So the mac address in a local admin variant.

Right, this is likely NetworkManager randomizing the mac for privacy
reasons.

Now our firmware has a requirement for the p2p-dev interface
that it
should be different from the mac address of the primary interface,
ie.
wlp1s0 in this log. In brcmfmac we try to do that by setting the
local
admin bit, but... as it is already set we end up using the same mac
address hence the -EBUSY.

Ah, that is good to know, so how can we fix this? Can userspace
specify a
different mac-address when it asks for the p2p-dev intf to be
created? Or
should we do something about this in the kernel?

So this is the patch I tested. Maybe you can verify it works for you
as well.

I can confirm that this fixes the errors, but I do not think that this
is a good
solution, using the permanent mac address for the p2p interface has
the
same
privacy problem as using it regularly. IMHO it would be best to just
generate
a random mac address if none is specified. This is what the kernel
seems
to do
in general when it needs a mac address and none is specified. You can
use the
eth_random_addr(u8 *addr) function for this, which will also set the
local
admin bit for you already.

Hi Hans,

Thanks for the suggestion. However, in wireless subsystem mac
randomization is requested by user-space upon scanning. This is still
possible with the p2p-dev interface.

The mac randomization that NetworkManager seemed to be doing is simply
changing the mac address of the network interface. I suppose it does
that repeatedly upon some interval?

I'm not familiar with the involved NetworkManager / wpa_supplicant code,
but I would assume it uses something smarter where the MAC does not
change while connected.

As the p2p-dev interface has no network interface associated with it
that is not possible. It can only specify a (random) mac address upon
creation.

Still I do not really object to use eth_random_addr() but it does not
give any real privacy so that should not be used as an argument. I
will respin the patches.

Great, thank you.

Ok. So I did sent out v3 of these patches, but now I am in doubt
because I decided to check the WFA P2P spec and here is what it says
about the P2P-Device address:

"""
The P2P Device Address of a P2P Device shall be its globally
administered MAC address, or its globally administered MAC address
with the locally administered bit set
"""

That is nice and all, but given all the efforts we've done to not make a
device uniquely identifiable to peers this seems like a bad idea. And
the peer
cannot really check this, so things should work fine anyways.

Let drop a bomb :-p MAC randomization is a stupid marketing trick to get the paranoid people into using a device so the big internet companies can keep perfect taps on them through the apps they use. Just a random thought from a different kind of paranoid guy.

I read the term "globally administered MAC address" as the permanent
mac address. Not sure if it really matters though. At least the P2P
discovery seems to be working. Did not get to setting up an actual P2P
connection yet.

Right, I don't think that this matters.

Indeed. Let's stick to v3.

Regards,
Arend

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