Hi Bruce, Thanks a lot for your reply, much appreciated. On Mon, Oct 12, 2020 at 10:26:02AM -0400, J. Bruce Fields wrote: > On Sun, Oct 11, 2020 at 09:59:13AM +0200, Salvatore Bonaccorso wrote: > > Hi > > > > On a system running 4.19.146-1 in Debian buster an issue got hit, > > while the server was under some slight load, but it does not seem > > easily reproducible, so asking if some more information can be > > provided to track/narrow this down. On the console the following was > > caught: > > Worth checking git logs of fs/nfsd/nfs4state.c and > fs/nfsd/nfs4callback.c. It might be > 2bbfed98a4d82ac4e7abfcd4eba40bddfc670b1d "nfsd: Fix races between > nfsd4_cb_release() and nfsd4_shutdown_callback()" ? That might be possible. As it was not possible to simply trigger the issue, do you know if it is possible to simply reproduce the issue fixed in the above? 2bbfed98a4d8 ("nfsd: Fix races between nfsd4_cb_release() and nfsd4_shutdown_callback()") would be missing in the v4.19.y stable series (as it was in 5.5-rc1 but not backported to other stable versions). Regards, Salvatore