From: J. Bruce Fields Date: Wed, 4 Feb 2009 22:35:38 +0000 (-0500) Subject: lockd: fix regression in lockd's handling of blocked locks X-Git-Tag: firefly_0821_release~15598^2 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=9d9b87c1218be78ddecbc85ec3bb91c79c1d56ab;p=firefly-linux-kernel-4.4.55.git lockd: fix regression in lockd's handling of blocked locks If a client requests a blocking lock, is denied, then requests it again, then here in nlmsvc_lock() we will call vfs_lock_file() without FL_SLEEP set, because we've already queued a block and don't need the locks code to do it again. But that means vfs_lock_file() will return -EAGAIN instead of FILE_LOCK_DENIED. So we still need to translate that -EAGAIN return into a nlm_lck_blocked error in this case, and put ourselves back on lockd's block list. The bug was introduced by bde74e4bc64415b1 "locks: add special return value for asynchronous locks". Thanks to Frank van Maarseveen for the report; his original test case was essentially for i in `seq 30`; do flock /nfsmount/foo sleep 10 & done Tested-by: Frank van Maarseveen Reported-by: Frank van Maarseveen Cc: Miklos Szeredi Signed-off-by: J. Bruce Fields --- diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c index 6063a8e4b9f3..763b78a6e9de 100644 --- a/fs/lockd/svclock.c +++ b/fs/lockd/svclock.c @@ -427,7 +427,7 @@ nlmsvc_lock(struct svc_rqst *rqstp, struct nlm_file *file, goto out; case -EAGAIN: ret = nlm_lck_denied; - goto out; + break; case FILE_LOCK_DEFERRED: if (wait) break; @@ -443,6 +443,10 @@ nlmsvc_lock(struct svc_rqst *rqstp, struct nlm_file *file, goto out; } + ret = nlm_lck_denied; + if (!wait) + goto out; + ret = nlm_lck_blocked; /* Append to list of blocked */