From 0e0af15b84e07e6763300dcd092b980086b9b9c4 Mon Sep 17 00:00:00 2001 From: Richard Purdie Date: Tue, 15 Jun 2021 12:00:33 -1000 Subject: cooker: Avoid parser deadlocks If you make parsing fail (e.g. add something like: X := "${@d.getVar('MCMACHINES').split()[1]}" to meson.bbclass, then run "while true; do bitbake -g bash; done" it will eventually hang. It appears the cancel_join_thread() call the parsing failure triggers, breaks the results_queue badly enough that it sits in read() indefintely (called from self.result_queue.get(timeout=0.25)). The timeout only applies to lock aquisition, not the read call. I've tried various other approaches such as using cancel_join_thread() in other places but the only way things don't lock up is to avoid cancel_join_thread() entirely for results_queue. I do have a concern that this may adversely affect Ctrl+C handling but equally, its broken now already and this appears to improve things. [YOCTO #14034] Signed-off-by: Richard Purdie Signed-off-by: Steve Sakoman Signed-off-by: Richard Purdie --- lib/bb/cooker.py | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/lib/bb/cooker.py b/lib/bb/cooker.py index 4d2c62cd9..730cdc56f 100644 --- a/lib/bb/cooker.py +++ b/lib/bb/cooker.py @@ -1933,7 +1933,8 @@ class Parser(multiprocessing.Process): except queue.Empty: pass else: - self.results.cancel_join_thread() + self.results.close() + self.results.join_thread() break if pending: @@ -1942,6 +1943,8 @@ class Parser(multiprocessing.Process): try: job = self.jobs.pop() except IndexError: + self.results.close() + self.results.join_thread() break result = self.parse(*job) # Clear the siggen cache after parsing to control memory usage, its huge @@ -2060,8 +2063,6 @@ class CookerParser(object): bb.event.fire(event, self.cfgdata) - # Allow data left in the cancel queue to be discarded - self.parser_quit.cancel_join_thread() for process in self.processes: self.parser_quit.put(None) @@ -2081,7 +2082,8 @@ class CookerParser(object): process.join() self.parser_quit.close() - self.parser_quit.join_thread() + # Allow data left in the cancel queue to be discarded + self.parser_quit.cancel_join_thread() sync = threading.Thread(target=self.bb_cache.sync) self.syncthread = sync -- cgit 1.2.3-korg