Re: [PATCH net-next v5 12/12] net: dsa: add driver for MaxLinear GSW1xx switch family

[Daniel Golle <daniel@makrotopia.org>]

On Thu, Oct 30, 2025 at 11:11:38PM +0000, Sverdlin, Alexander wrote:
> [...]
> For some reason with both v4 and v5 I can reliably reproduce the following
> warning (ASSERT_RTNL()) at the very beginning of
> drivers/net/dsa/local_termination.sh selftest:
> 
> RTNL: assertion failed at git/net/core/dev.c (9480)
> WARNING: CPU: 1 PID: 529 at git/net/core/dev.c:9480 __dev_set_promiscuity+0x174/0x188
> CPU: 1 UID: 996 PID: 529 Comm: systemd-resolve Tainted: G           O        6.18.0-rc2+gite9079300094d #1 PREEMPT 
> pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> pc : __dev_set_promiscuity+0x174/0x188
> lr : __dev_set_promiscuity+0x174/0x188
> Call trace:
>  __dev_set_promiscuity+0x174/0x188 (P)
>  __dev_set_rx_mode+0xa0/0xb0
>  dev_mc_del+0x94/0xc0
>  igmp6_group_dropped+0x124/0x410
>  __ipv6_dev_mc_dec+0x108/0x168
>  __ipv6_sock_mc_drop+0x64/0x188
>  ipv6_sock_mc_drop+0x140/0x170
>  do_ipv6_setsockopt+0x1408/0x1828
>  ipv6_setsockopt+0x64/0xf8
>  udpv6_setsockopt+0x28/0x58
>  sock_common_setsockopt+0x24/0x38
>  do_sock_setsockopt+0x78/0x158
>  __sys_setsockopt+0x88/0x110
>  __arm64_sys_setsockopt+0x30/0x48
>  invoke_syscall+0x50/0x120
>  el0_svc_common.constprop.0+0xc8/0xf0
>  do_el0_svc+0x24/0x38
>  el0_svc+0x50/0x2b0
>  el0t_64_sync_handler+0xa0/0xe8
>  el0t_64_sync+0x198/0x1a0
> 
> (testing with GSW145)
> I'm not sure though, if it's related to the gsw1xx code, am65-cpsw-nuss driver
> on my CPU port or if it's a fresh regression in net-next...
> 
> I can see the above splat if I apply the patchset onto bfe62db5422b1a5f25752bd0877a097d436d876d
> but not with older patchset on top of e90576829ce47a46838685153494bc12cd1bc333.
> 
> I'll try to bisect the underlying net-next...

Did you try to rebase the patches necessary for the GSW145 on top of the
last known-to-work net-next commit?

Also note that I've successfully tested local_termination.sh on top
of ea7d0d60ebc9bddf3ad768557dfa1495bc032bf6, but using the modified
RaspberryPi 4B provided by MaxLinear, so there obviously is a different
Ethernet driver on the CPU port...