From: Julian Schroeder <jumaco@xxxxxxxxxx>
Date: Fri, 20 May 2022 18:33:27 +0000
Subject: [PATCH] nfsd: destroy percpu stats counters after reply cache
shutdown
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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 (â??nfsd: protect concurrent access to nfsd stats countersâ??)
Signed-off-by: Julian Schroeder <jumaco@xxxxxxxxxx>
---
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 0b3f12aa37ff..7da88bdc0d6c 100644
--- a/fs/nfsd/nfscache.c
+++ b/fs/nfsd/nfscache.c
@@ -206,7 +206,6 @@ 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++) {
@@ -217,6 +216,7 @@ 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;
--
2.32.0
