From: Trond Myklebust LOCKD: Fix a deadlock in nlm_traverse_files() nlm_traverse_files() is not allowed to hold the nlm_file_mutex while calling nlm_inspect file, since it may end up calling nlm_release_file() when releaseing the blocks. Signed-off-by: Trond Myklebust --- fs/lockd/svcsubs.c | 15 +++++++++------ 1 files changed, 9 insertions(+), 6 deletions(-) diff --git a/fs/lockd/svcsubs.c b/fs/lockd/svcsubs.c index 2a4df9b..01b4db9 100644 --- a/fs/lockd/svcsubs.c +++ b/fs/lockd/svcsubs.c @@ -237,19 +237,22 @@ static int nlm_traverse_files(struct nlm_host *host, int action) { struct nlm_file *file, **fp; - int i; + int i, ret = 0; mutex_lock(&nlm_file_mutex); for (i = 0; i < FILE_NRHASH; i++) { fp = nlm_files + i; while ((file = *fp) != NULL) { + file->f_count++; + mutex_unlock(&nlm_file_mutex); + /* Traverse locks, blocks and shares of this file * and update file->f_locks count */ - if (nlm_inspect_file(host, file, action)) { - mutex_unlock(&nlm_file_mutex); - return 1; - } + if (nlm_inspect_file(host, file, action)) + ret = 1; + mutex_lock(&nlm_file_mutex); + file->f_count--; /* No more references to this file. Let go of it. */ if (!file->f_blocks && !file->f_locks && !file->f_shares && !file->f_count) { @@ -262,7 +265,7 @@ nlm_traverse_files(struct nlm_host *host } } mutex_unlock(&nlm_file_mutex); - return 0; + return ret; } /*