If pthread_cond_wait fails and the thread worker ends, make sure to unlock retire_mutex, which has been locked for the condition. The return value of pthread_mutex_unlock is ignored, as there's nothing that can be done with it at that point. --- df/parallel.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/df/parallel.c b/df/parallel.c index 047735e..6d2e1cf 100644 --- a/df/parallel.c +++ b/df/parallel.c @@ -33,6 +33,8 @@ #include <libvirt/virterror.h> #endif +#include "ignore-value.h" + #include "guestfs.h" #include "guestfs-internal-frontend.h" #include "options.h" @@ -224,6 +226,7 @@ worker_thread (void *thread_data_vp) if (err != 0) { thread_failure ("pthread_cond_wait", err); thread_data->r = -1; + ignore_value (pthread_mutex_unlock (&retire_mutex)); return &thread_data->r; } } -- 1.9.3