On Saturday, April 09, 2016 06:31:24 PM Bjoern A. Zeeb wrote: > On Sat, 9 Apr 2016, John Baldwin wrote: > > trash user data. In the rest of the tree, we tend to prefer marking items > > as NOFREE instead of this approach putting a priority on stability and > > reliability over memory efficiency. > > > > For all of the zones that you removed NOFREE from, do you know why that was > > added in the first place (e.g. which stale pointers to pcbs could be > > referenced after free)? Did you verify that those conditions have been > > fixed? > > I did check. I did check a few years ago (and I think you had > reviewed that; maybe it was trouble). And the TCP bits here were > the last ones that were problematic back then. With the changes from > r281599 this should no longer be a problem. > > As for the others, a few years ago Andre already removed the NOFREE > and we unconditionally made him back the change out, which was a > mistake as otherwise some of these zones would have been "clean" for > years. Others have had KASSERTs ensuring that on VNET stack they were > actually empty.
Ok. I believe one of the old ones fixed long ago were the pcb sysctls. I couldn't recall any other cases that required NOFREE. The network stack is often fairly loose with references especially those that add per-packet overhead (at least historically, the ifnet reference in m_pkthdr is one of the "big" remaining issues IIRC), so I sort of assume it still needs NOFREE as a general rule. -- John Baldwin _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
