From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff King Subject: [PATCH 4/4] send-pack: abort sideband demuxer on pack-objects error Date: Thu, 31 Mar 2011 14:44:43 -0400 Message-ID: <20110331184443.GD16906@sigill.intra.peff.net> References: <20110331184243.GA12027@sigill.intra.peff.net> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Cc: Johannes Sixt To: git@vger.kernel.org X-From: git-owner@vger.kernel.org Thu Mar 31 20:44:56 2011 Return-path: Envelope-to: gcvg-git-2@lo.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Q5MrW-0001qe-L9 for gcvg-git-2@lo.gmane.org; Thu, 31 Mar 2011 20:44:54 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759052Ab1CaSot (ORCPT ); Thu, 31 Mar 2011 14:44:49 -0400 Received: from 99-108-226-0.lightspeed.iplsin.sbcglobal.net ([99.108.226.0]:34927 "EHLO peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759048Ab1CaSot (ORCPT ); Thu, 31 Mar 2011 14:44:49 -0400 Received: (qmail 1394 invoked by uid 107); 31 Mar 2011 18:45:29 -0000 Received: from sigill.intra.peff.net (HELO sigill.intra.peff.net) (10.0.0.7) (smtp-auth username relayok, mechanism cram-md5) by peff.net (qpsmtpd/0.84) with ESMTPA; Thu, 31 Mar 2011 14:45:29 -0400 Received: by sigill.intra.peff.net (sSMTP sendmail emulation); Thu, 31 Mar 2011 14:44:43 -0400 Content-Disposition: inline In-Reply-To: <20110331184243.GA12027@sigill.intra.peff.net> Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: If pack-objects dies prematurely (for example, because there is some repo corruption), we are careful to clean up the sideband demuxer (if it is being used) with finish_async. However, for an async implementation which forks (i.e., not Windows), that means we will waitpid() for the async process. Meanwhile, the async sideband demuxer will continue trying to stream data from the remote repo until it gets EOF. Depending on what data pack-objects actually sent, the remote repo may not actually send anything (e.g., if we sent nothing and it is simply waiting for the pack). This leads to deadlock cycle in which send-pack waits on the demuxer, the demuxer waits on the remote receive-pack, and the remote receive-pack waits on send-pack to send the pack data. To break this, let's have send-pack abort the demuxer when it knows that it has failed to properly send the pack. Signed-off-by: Jeff King --- builtin-send-pack.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/builtin-send-pack.c b/builtin-send-pack.c index 2478e18..cc068ff 100644 --- a/builtin-send-pack.c +++ b/builtin-send-pack.c @@ -516,7 +516,7 @@ int send_pack(struct send_pack_args *args, for (ref = remote_refs; ref; ref = ref->next) ref->status = REF_STATUS_NONE; if (use_sideband) - finish_async(&demux); + abort_async(&demux); return -1; } } -- 1.7.4.13.g8566c