Re: [PATCH] rhashtable: Fix potential deadlock by moving schedule_work outside lock

[Breno Leitao]

Hello Herbet,

On Fri, Jan 10, 2025 at 05:27:49PM +0800, Herbert Xu wrote:

> Sorry, I think it was my addition that broke things.  The condition
> for checking whether an entry is inserted is incorrect, thus resulting
> in an underflow of the number of entries after entry removal.

That is what I though originally as well, but I was not convinced. While
reading the code, I understood that, if new_tbl is not NULL, then
PTR_ERR(data) will be -ENOENT.

In which case `net_tbl` will not be NULL, and PTR_ERR(data) != -ENOENT?

Thanks for solving it.

> Please test this patch:

I don't have an easy reproducer yet, but, I will get this patch in ~50
hosts and see if any of them misbehave during the weekend.

Misbehaving in my case is strongly associate with messages like the
following being printed:

	kobject_uevent: unable to create netlink socket!


Thanks
--breno