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Date: Fri, 13 Jun 2025 16:56:36 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Stanislav Fomichev <stfomichev@gmail.com>
Cc: syzbot <syzbot+b8c48ea38ca27d150063@syzkaller.appspotmail.com>,
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 syzkaller-bugs@googlegroups.com
Subject: Re: [syzbot] [net?] WARNING in __linkwatch_sync_dev (2)
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On Thu, 12 Jun 2025 18:09:02 -0700 Stanislav Fomichev wrote:
> Where linkwatch_do_dev (potentially called from ethtool_op_get_link and
> bond_check_dev_link) might trigger ipv6 address assignment so I'm not
> sure how this all supposed to work under rcu and without rtnl lock.

Yeah, linkwatch seems to also try to allocate memory with GFP_KERNEL.

> Tentatively (untested uncompiled):

I think miimon recheck period may be rather frequent, but given 
the above going back to rtnl is probably the sanest way out.