From: Julian Schroeder jumaco@amazon.com
[ Upstream commit fd5e363eac77ef81542db77ddad0559fa0f9204e ]
Upon nfsd shutdown any pending DRC cache is freed. DRC cache use is tracked via a percpu counter. In the current code the percpu counter is destroyed before. If any pending cache is still present, percpu_counter_add is called with a percpu counter==NULL. This causes a kernel crash. The solution is to destroy the percpu counter after the cache is freed.
Fixes: e567b98ce9a4b (“nfsd: protect concurrent access to nfsd stats counters”) Signed-off-by: Julian Schroeder jumaco@amazon.com Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/nfsd/nfscache.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/nfsd/nfscache.c b/fs/nfsd/nfscache.c index a4a69ab6ab28..a83890950290 100644 --- a/fs/nfsd/nfscache.c +++ b/fs/nfsd/nfscache.c @@ -212,7 +212,6 @@ void nfsd_reply_cache_shutdown(struct nfsd_net *nn) struct svc_cacherep *rp; unsigned int i;
- nfsd_reply_cache_stats_destroy(nn); unregister_shrinker(&nn->nfsd_reply_cache_shrinker);
for (i = 0; i < nn->drc_hashsize; i++) { @@ -223,6 +222,7 @@ void nfsd_reply_cache_shutdown(struct nfsd_net *nn) rp, nn); } } + nfsd_reply_cache_stats_destroy(nn);
kvfree(nn->drc_hashtbl); nn->drc_hashtbl = NULL;