Re: [RFC PATCH 0/9] Move the audit netlink multicast send to the kauditd_thread

This patchset started off innocently enough with the goal of moving the netlink multicast send from audit_log_end() to kauditd_thread(). However, things escalated rather quickly as this uncovered, or made worse, a number of inherent problems in the audit backlog queues. This patchset attempts to address both the multicast and queue problems. I've spent a few weeks playing with this, stressing it a bit, and tweaking some of the logic and so far it is performing at least as well as the existing code for all the scenarios I've thrown at it; if you happen to have a particularly nasty audit test, I'd appreciate hearing about it, and I'd appreciate it even more if you could give it a test too. I'm posting this patchset as a RFC because this is a pretty big change to some rather critical code and I thought some review would be prudent; if I don't see anything substantial by next week I'll go ahead and merge this into audit#next, along with the patch from WANG Cong which started the little endeavor (see the links below). You'll note I'm not including the patch from WANG Cong in this patchset for the sake of clarity. Enough from me, please take a look at the patchset that follows and post any comments you may have to the list. In case you are running Fedora Rawhide, I've been building some kernels you can use to test at the link below: * GitHub Issue Trackers - https://github.com/linux-audit/audit-kernel/issues/23 - https://github.com/linux-audit/audit-kernel/issues/22 * Fedora Rawhide Kernel Builds - https://copr.fedorainfracloud.org/coprs/pcmoore/kernel-testing