From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44840) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dxP4M-0006Wb-Br for qemu-devel@nongnu.org; Wed, 27 Sep 2017 23:00:59 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dxP4L-0002Qo-Mw for qemu-devel@nongnu.org; Wed, 27 Sep 2017 23:00:58 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46552) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dxP4L-0002QQ-IA for qemu-devel@nongnu.org; Wed, 27 Sep 2017 23:00:57 -0400 From: Peter Xu Date: Thu, 28 Sep 2017 10:59:58 +0800 Message-Id: <20170928025958.1420-6-peterx@redhat.com> In-Reply-To: <20170928025958.1420-1-peterx@redhat.com> References: <20170928025958.1420-1-peterx@redhat.com> Subject: [Qemu-devel] [PATCH v4 5/5] aio: fix assert when remove poll during destroy List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Paolo Bonzini , "Daniel P . Berrange" , Stefan Hajnoczi , Fam Zheng , peterx@redhat.com, =?UTF-8?q?Andreas=20F=C3=A4rber?= , Manos Pitsidianakis , "Dr . David Alan Gilbert" , Stefan Hajnoczi From: Stefan Hajnoczi After iothread is enabled internally inside QEMU with GMainContext, we may encounter this warning when destroying the iothread: (qemu-system-x86_64:19925): GLib-CRITICAL **: g_source_remove_poll: assertion '!SOURCE_DESTROYED (source)' failed The problem is that g_source_remove_poll() does not allow to remove one source from array if the source is detached from its owner context. (peterx: which IMHO does not make much sense) Fix it on QEMU side by avoid calling g_source_remove_poll() if we know the object is during destruction, and we won't leak anything after all since the array will be gone soon cleanly even with that fd. Signed-off-by: Stefan Hajnoczi [peterx: write the commit message] Signed-off-by: Peter Xu --- util/aio-posix.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/util/aio-posix.c b/util/aio-posix.c index 2d51239ec6..5946ac09f0 100644 --- a/util/aio-posix.c +++ b/util/aio-posix.c @@ -223,7 +223,14 @@ void aio_set_fd_handler(AioContext *ctx, return; } - g_source_remove_poll(&ctx->source, &node->pfd); + /* If the GSource is in the process of being destroyed then + * g_source_remove_poll() causes an assertion failure. Skip + * removal in that case, because glib cleans up its state during + * destruction anyway. + */ + if (!g_source_is_destroyed(&ctx->source)) { + g_source_remove_poll(&ctx->source, &node->pfd); + } /* If the lock is held, just mark the node as deleted */ if (qemu_lockcnt_count(&ctx->list_lock)) { -- 2.13.5