From mboxrd@z Thu Jan 1 00:00:00 1970 From: Junio C Hamano Subject: Re: [PATCH] t9010: Open backflow FIFO once to work around kernel race condition Date: Tue, 26 Jun 2012 15:58:39 -0700 Message-ID: <7vsjdh8yu8.fsf@alter.siamese.dyndns.org> References: <1340749806-22734-1-git-send-email-andersk@mit.edu> <20120626224053.GA7155@burratino> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-2022-jp Cc: Anders Kaseorg , David Barr , git@vger.kernel.org To: Jonathan Nieder X-From: git-owner@vger.kernel.org Wed Jun 27 00:58:55 2012 Return-path: Envelope-to: gcvg-git-2@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Sjeif-00077K-Hj for gcvg-git-2@plane.gmane.org; Wed, 27 Jun 2012 00:58:49 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754508Ab2FZW6p (ORCPT ); Tue, 26 Jun 2012 18:58:45 -0400 Received: from b-pb-sasl-quonix.pobox.com ([208.72.237.35]:52845 "EHLO smtp.pobox.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754357Ab2FZW6p (ORCPT ); Tue, 26 Jun 2012 18:58:45 -0400 Received: from smtp.pobox.com (unknown [127.0.0.1]) by b-sasl-quonix.pobox.com (Postfix) with ESMTP id CC29B8A89; Tue, 26 Jun 2012 18:58:44 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=pobox.com; h=from:to:cc :subject:references:date:in-reply-to:message-id:mime-version :content-type; s=sasl; bh=ZyUeVIjgDkTB+ILhrkn9/bIOqJE=; b=ad2mi7 eQoduzYQMWROoPl+2ld0D7XiybZl9uSPWFcitYzYGgZjZ7AWXF4uSKYw+D2zrNfg LjapOaPKlZGfLWnpS1rOrAR6bOPM1MkYPgZGV14PULtht5zfYlDuXa7HlTrnJERu qexkRxznxLijNfBgyjsOQCq2cTHdkSbYfMe48= DomainKey-Signature: a=rsa-sha1; c=nofws; d=pobox.com; h=from:to:cc :subject:references:date:in-reply-to:message-id:mime-version :content-type; q=dns; s=sasl; b=LkBpTLqj+Em0t0xJdg9tPPVKXxAWKjSx ovQRN/+f9lri+WRZdV0lpUgeKVtM9VwNtQsXwinGGQ2nY4w7Zq1DzyDXeoJ9dxbI cb5HDfyMiTVwxvbZBCvKKZ7wLNXAvI/znQz+g81jesHhS3Wc3k59/wu2WhJarMAU t5l7ip0nxa8= Received: from b-pb-sasl-quonix.pobox.com (unknown [127.0.0.1]) by b-sasl-quonix.pobox.com (Postfix) with ESMTP id C38568A88; Tue, 26 Jun 2012 18:58:44 -0400 (EDT) Received: from pobox.com (unknown [98.234.214.94]) (using TLSv1 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by b-sasl-quonix.pobox.com (Postfix) with ESMTPSA id 36A148A86; Tue, 26 Jun 2012 18:58:41 -0400 (EDT) In-Reply-To: <20120626224053.GA7155@burratino> (Jonathan Nieder's message of "Tue, 26 Jun 2012 17:40:53 -0500") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.2 (gnu/linux) X-Pobox-Relay-ID: 790EC2E4-BFE2-11E1-BF17-FC762E706CDE-77302942!b-pb-sasl-quonix.pobox.com Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Jonathan Nieder writes: > Hi, > > Quick first impressions: > > Anders Kaseorg wrote: > >> Sidestep this problem by opening the backflow FIFO once for >> read+write. > > Is that portable? If you mean [n]<>word, it probably is, even though it is somewhat unusual and I wouldn't be surprised if implementations get wrong. >> Also, replace the stream FIFO with a shell pipe so we >> don’t have to do manual process management. > > Doesn't this mean we wouldn't notice if test-svn-fe crashes? Very good point.