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| author | Keir Fraser <keir.fraser@citrix.com> | 2010-05-12 08:49:13 +0100 |
|---|---|---|
| committer | Keir Fraser <keir.fraser@citrix.com> | 2010-05-12 08:49:13 +0100 |
| commit | 990e331218dba6b671854cec24f639ff45763d7d (patch) | |
| tree | e97efe2c1972c4a9bc696072f2fcadd0cdeaea3c /tools/xenstore | |
| parent | 20a817b0a72cbc330d1278552aa8d328940d1e7c (diff) | |
| download | xen-990e331218dba6b671854cec24f639ff45763d7d.tar.gz xen-990e331218dba6b671854cec24f639ff45763d7d.tar.bz2 xen-990e331218dba6b671854cec24f639ff45763d7d.zip | |
xs: avoid pthread_join deadlock in xs_daemon_close
Doing a pthread_cancel and join on the reader thread while holding all
the request/reply/watch mutexes can deadlock if the thread needs to
take any of those mutexes to exit. Kill off the reader thread before
taking any mutexes (which should be redundant if we're
single-threaded at that point).
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Diffstat (limited to 'tools/xenstore')
| -rw-r--r-- | tools/xenstore/xs.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/tools/xenstore/xs.c b/tools/xenstore/xs.c index 6a87ccf708..53e3d44345 100644 --- a/tools/xenstore/xs.c +++ b/tools/xenstore/xs.c @@ -260,10 +260,6 @@ void xs_daemon_destroy_postfork(struct xs_handle *h) void xs_daemon_close(struct xs_handle *h) { - mutex_lock(&h->request_mutex); - mutex_lock(&h->reply_mutex); - mutex_lock(&h->watch_mutex); - #ifdef USE_PTHREAD if (h->read_thr_exists) { pthread_cancel(h->read_thr); @@ -271,6 +267,10 @@ void xs_daemon_close(struct xs_handle *h) } #endif + mutex_lock(&h->request_mutex); + mutex_lock(&h->reply_mutex); + mutex_lock(&h->watch_mutex); + close_free_msgs(h); mutex_unlock(&h->request_mutex); |