Re: rtnl_mutex deadlock?

On Thu, Aug 06, 2015 at 04:50:39PM +0200, Daniel Borkmann wrote:

Then, in __rhashtable_insert_fast(), I could trigger an -EBUSY when I'm
really unlucky and exceed the ht->elasticity limit of 16. I would then
end up in rhashtable_insert_rehash() to find out there's already one
ongoing and thus, I'm getting -EBUSY via __netlink_insert().

Right, so the only way you can trigger this is if you hit a chain
longer than 16 and the number of entries in the table is less than
75% the size of the table, as well as there being an existing resize
or rehash operation.

This should be pretty much impossible.

But if we had a WARN_ON_ONCE there then we'll know for sure.

Cheers,
-- 
Email: Herbert Xu [off-list ref]
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