Hello Oleg,
On 3/28/2025 10:30 PM, Oleg Nesterov wrote:
Dear syzbot,
On 03/28, syzbot wrote:
syzbot has tested the proposed patch and the reproducer did not trigger any issue:
Reported-by: syzbot+62262fdc0e01d99573fc@xxxxxxxxxxxxxxxxxxxxxxxxx
Tested-by: syzbot+62262fdc0e01d99573fc@xxxxxxxxxxxxxxxxxxxxxxxxx
Yours is the right approach. I was searching for p9_poll_mux()
which would wake the read collector to free pipe buffers but I
didn't dig enough and I was too lazy to open code it (guilty!)
If this gets picked, feel free to add:
Reviewed-and-tested-by: K Prateek Nayak <kprateek.nayak@xxxxxxx>
Thanks. so the previous
syzbot has tested the proposed patch but the reproducer is still triggering an issue:
unregister_netdevice: waiting for DEV to become free
unregister_netdevice: waiting for batadv0 to become free. Usage count = 3
report suggests that upstream/master has another/unrelated issue(s).
I could not reproduce this bit on mainline at commit acb4f33713b9
("Merge tag 'm68knommu-for-v6.15' of
git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu") so I too
second that it is an unrelated issue.
As for the patches from me or Prateek (thanks again!), I think that
the maintainers should take a look.
But at this point I am mostly confident that the bisected commit aaec5a95d5961
("pipe_read: don't wake up the writer if the pipe is still full") is innocent,
it just reveals yet another problem.
I guess (I hope ;) Prateek agrees.
I agree aaec5a95d5961 is not guilty! (unlike me) :)
Oleg.
--
Thanks and Regards,
Prateek
