5.10-stable review patch. If anyone has any objections, please let me know.
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From: NeilBrown neilb@suse.de
[ Upstream commit 665e89ab7c5af1f2d260834c861a74b01a30f95f ]
The below-mentioned patch was intended to simplify refcounting on the svc_serv used by locked. The goal was to only ever have a single reference from the single thread. To that end we dropped a call to lockd_start_svc() (except when creating thread) which would take a reference, and dropped the svc_put(serv) that would drop that reference.
Unfortunately we didn't also remove the svc_get() from lockd_create_svc() in the case where the svc_serv already existed. So after the patch: - on the first call the svc_serv was allocated and the one reference was given to the thread, so there are no extra references - on subsequent calls svc_get() was called so there is now an extra reference. This is clearly not consistent.
The inconsistency is also clear in the current code in lockd_get() takes *two* references, one on nlmsvc_serv and one by incrementing nlmsvc_users. This clearly does not match lockd_put().
So: drop that svc_get() from lockd_get() (which used to be in lockd_create_svc().
Reported-by: Ido Schimmel idosch@idosch.org Closes: https://lore.kernel.org/linux-nfs/ZHsI%2FH16VX9kJQX1@shredder/T/#u Fixes: b73a2972041b ("lockd: move lockd_start_svc() call into lockd_create_svc()") Signed-off-by: NeilBrown neilb@suse.de Tested-by: Ido Schimmel idosch@nvidia.com Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/lockd/svc.c | 1 - 1 file changed, 1 deletion(-)
diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c index 59ef8a1f843f3..5579e67da17db 100644 --- a/fs/lockd/svc.c +++ b/fs/lockd/svc.c @@ -355,7 +355,6 @@ static int lockd_get(void) int error;
if (nlmsvc_serv) { - svc_get(nlmsvc_serv); nlmsvc_users++; return 0; }