| Message ID | 20220523185226.7614-1-jumaco@dev-dsk-jumaco-1e-78723413.us-east-1.amazon.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | nfsd: destroy percpu stats counters after reply cache shutdown | expand |
> On May 23, 2022, at 2:52 PM, Julian Schroeder <jumaco@dev-dsk-jumaco-1e-78723413.us-east-1.amazon.com> wrote: > > From: Julian Schroeder <jumaco@amazon.com> > > 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> > --- > 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 > Thank you, Julian. Patch applied to the NFSD for-5.19 topic branch. -- Chuck Lever
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;