Hello,
after upgrading Linux from 5.13.13 to 5.14.0 on my router with this wireless
device:
03:00.0 Network controller [0280]: Qualcomm Atheros AR93xx Wireless Network Adapter [168c:0030] (rev 01)
Subsystem: Qualcomm Atheros AR93xx Wireless Network Adapter [168c:3116]
Flags: bus master, fast devsel, latency 0, IRQ 18
Memory at 81200000 (64-bit, non-prefetchable) [size=128K]
Expansion ROM at 81220000 [disabled] [size=64K]
Capabilities: [40] Power Management version 3
Capabilities: [50] MSI: Enable- Count=1/4 Maskable+ 64bit+
Capabilities: [70] Express Endpoint, MSI 00
Capabilities: [100] Advanced Error Reporting
Capabilities: [140] Virtual Channel
Capabilities: [300] Device Serial Number 00-00-00-00-00-00-00-00
Kernel driver in use: ath9k
Kernel modules: ath9k
which works as a WiFi accesspoint, I noticed that WiFi clients cannot use IPv6
anymore. The problem is that the router cannot translate an IPv6 address of
the client to a MAC address. The reason is that IPv6 multicast packets used by
ICMPv6 neighbour discovery protocol do not reach the clients. In other words
the ath9k-driven device stopped transmitting multicast frames.
This can be reproduced with "ndisc6 -r 100 fe80::217:c4ff:fe4e:1552 wlan0"
command which queries (100 times) fe80::217:c4ff:fe4e:1552 address of
my client from the router. tcpdump on the ath9k device shows the queries,
but tcpdump on the client cannot see them.
The other way works correctly. I observed this with all two WiFi clients
I have (Pixel 3a phone, and a laptop with a Realtek chip). Upgrading to 5.14.1
did not help. Once I rebooted to 5.13.13, the functionality was restored.
Therefore I conclude this is regression in 5.14.0 Linux.
-- Petr
V Sat, Sep 04, 2021 at 08:20:57PM +0200, Petr Pisar napsal(a):
Hello,
after upgrading Linux from 5.13.13 to 5.14.0 on my router with this wireless
device:
03:00.0 Network controller [0280]: Qualcomm Atheros AR93xx Wireless Network Adapter [168c:0030] (rev 01)
Subsystem: Qualcomm Atheros AR93xx Wireless Network Adapter [168c:3116]
Flags: bus master, fast devsel, latency 0, IRQ 18
Memory at 81200000 (64-bit, non-prefetchable) [size=128K]
Expansion ROM at 81220000 [disabled] [size=64K]
Capabilities: [40] Power Management version 3
Capabilities: [50] MSI: Enable- Count=1/4 Maskable+ 64bit+
Capabilities: [70] Express Endpoint, MSI 00
Capabilities: [100] Advanced Error Reporting
Capabilities: [140] Virtual Channel
Capabilities: [300] Device Serial Number 00-00-00-00-00-00-00-00
Kernel driver in use: ath9k
Kernel modules: ath9k
which works as a WiFi accesspoint, I noticed that WiFi clients cannot use IPv6
anymore. The problem is that the router cannot translate an IPv6 address of
the client to a MAC address. The reason is that IPv6 multicast packets used by
ICMPv6 neighbour discovery protocol do not reach the clients. In other words
the ath9k-driven device stopped transmitting multicast frames.
The same observation was reported here by Felix Fietkau in "[PATCH] Revert
"mac80211: do not use low data rates for data frames with no ack flag""
<https://marc.info/?l=linux-wireless&m=163091738109000&w=2> with a proposal to
revert the offending d333322361e7a099dc74df2498d3fa5fde5c4fa7 commit.
-- Petr
Petr Pisar [off-list ref] writes:
V Sat, Sep 04, 2021 at 08:20:57PM +0200, Petr Pisar napsal(a):
quoted
Hello,
after upgrading Linux from 5.13.13 to 5.14.0 on my router with this wireless
device:
03:00.0 Network controller [0280]: Qualcomm Atheros AR93xx Wireless Network Adapter [168c:0030] (rev 01)
Subsystem: Qualcomm Atheros AR93xx Wireless Network Adapter [168c:3116]
Flags: bus master, fast devsel, latency 0, IRQ 18
Memory at 81200000 (64-bit, non-prefetchable) [size=128K]
Expansion ROM at 81220000 [disabled] [size=64K]
Capabilities: [40] Power Management version 3
Capabilities: [50] MSI: Enable- Count=1/4 Maskable+ 64bit+
Capabilities: [70] Express Endpoint, MSI 00
Capabilities: [100] Advanced Error Reporting
Capabilities: [140] Virtual Channel
Capabilities: [300] Device Serial Number 00-00-00-00-00-00-00-00
Kernel driver in use: ath9k
Kernel modules: ath9k
which works as a WiFi accesspoint, I noticed that WiFi clients cannot use IPv6
anymore. The problem is that the router cannot translate an IPv6 address of
the client to a MAC address. The reason is that IPv6 multicast packets used by
ICMPv6 neighbour discovery protocol do not reach the clients. In other words
the ath9k-driven device stopped transmitting multicast frames.
The same observation was reported here by Felix Fietkau in "[PATCH] Revert
"mac80211: do not use low data rates for data frames with no ack flag""
<https://marc.info/?l=linux-wireless&m=163091738109000&w=2> with a proposal to
revert the offending d333322361e7a099dc74df2498d3fa5fde5c4fa7 commit.
Very good, thanks for the followup.
--
https://patchwork.kernel.org/project/linux-wireless/list/
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches