From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from out3-smtp.messagingengine.com (out3-smtp.messagingengine.com [66.111.4.27]) by sourceware.org (Postfix) with ESMTPS id 830773858D1E for ; Fri, 21 Oct 2022 01:41:04 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 830773858D1E Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=sunshowers.io Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=sunshowers.io Received: from compute3.internal (compute3.nyi.internal [10.202.2.43]) by mailout.nyi.internal (Postfix) with ESMTP id BF5715C0097; Thu, 20 Oct 2022 21:41:01 -0400 (EDT) Received: from imap49 ([10.202.2.99]) by compute3.internal (MEProxy); Thu, 20 Oct 2022 21:41:01 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sunshowers.io; h=cc:cc:content-type:date:date:from:from:in-reply-to :in-reply-to:message-id:mime-version:references:reply-to:sender :subject:subject:to:to; s=fm1; t=1666316461; x=1666402861; bh=3B oev1d/a1lqTucwgboqtqg4LCu0IlQRr3HOTyNg9Rk=; b=nxHQAkVB69umCqVEyc vj62Daa3zZqte7RjNwR9BVAgJu9XncU69BCZD2jeH0OL8kSzRpyNlBe9bVhFsV4f tEuaC3swGKRWub/Dp36F9bhL4FqWHH74rffWLwm1b4rB83lyOXuvlYWRm2VPs7vs 18JWQCbHK2Z/Gr5Ln2+a084/VTWGbuJ2e1BarX0xXLh1n7985Hf93QJy3MPkddF3 XWp58roYQGEgTh4CosLfR37zOPZYDJ0USIb7pQLjRLHJNNxdCGt0MtP1rA9c0+eA YwCELv1X28auPQspvKgyXidqul7VwvFiCE+Y4534bQwh8GJjbE3gXN3P+zk8Wsr9 F9eA== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:date:date:feedback-id :feedback-id:from:from:in-reply-to:in-reply-to:message-id :mime-version:references:reply-to:sender:subject:subject:to:to :x-me-proxy:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s= fm3; t=1666316461; x=1666402861; bh=3Boev1d/a1lqTucwgboqtqg4LCu0 IlQRr3HOTyNg9Rk=; b=Egrzlk4jpXlb0H8uKe3A1WEV5JgZLuBpbFQIbVyWD4wD OrOOLRqGXfMsYaGIW/4L5fv8Gv+IuoKLZWhYbFwts6YfqBkoFTOqZtXeCvhL+WDb TrtPJ7cBNDrDcpveZjXZ/KcyhXEc2uPv8vJFRhhoWQv2//r2E1XXABQ0qO8AfVTH q+MLHl7vcHUxF8ZX67L7NmxkzSxYeeezZnYZ+QMFgqRu+MJP76M9nxZ1ajkowSNW JqM8HS5ZNAd/o6oEA26zxWxN9PUfGJHjsXr3U3nzD7JW+Oa4CbeXX054UbRpTto1 fIbWvuLEHyylVkX+r3GuIm0sJURxafJZVVX1XrsKbw== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvfedrfeeljedgheduucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhepofgfggfkjghffffhvfevufgtsehttdertderredtnecuhfhrohhmpeftrghi nhcuoehglhhisggtsehsuhhnshhhohifvghrshdrihhoqeenucggtffrrghtthgvrhhnpe efgfejkefhvdfgfedvlefgtedugfetieffjedtheeifeetffdvtdefhfffiefgieenucev lhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpehglhhisggtse hsuhhnshhhohifvghrshdrihho X-ME-Proxy: Feedback-ID: i552946fd:Fastmail Received: by mailuser.nyi.internal (Postfix, from userid 501) id 7202D15A0087; Thu, 20 Oct 2022 21:41:01 -0400 (EDT) X-Mailer: MessagingEngine.com Webmail Interface User-Agent: Cyrus-JMAP/3.7.0-alpha0-1047-g9e4af4ada4-fm-20221005.001-g9e4af4ad Mime-Version: 1.0 Message-Id: <1ccd76de-6d37-4e77-9142-c5c330bde8ca@app.fastmail.com> In-Reply-To: <87zgdqd7zx.fsf@oldenburg.str.redhat.com> References: <2921668c-773e-465d-9480-0abb6f979bf9@www.fastmail.com> <7727e4de-a8da-1e6b-4d7c-68a132750996@linaro.org> <64917a2f-788b-4695-b799-63bbb8a4873f@www.fastmail.com> <87tu64w33v.fsf@oldenburg.str.redhat.com> <7c356365-34db-cc00-bb92-0e55e7a89118@linaro.org> <877d27vbdx.fsf@oldenburg.str.redhat.com> <5bcba9d3-7bdd-1855-afb7-1f9d63014842@linaro.org> <87leqbmwkl.fsf@oldenburg.str.redhat.com> <87leqb1f9j.fsf@oldenburg.str.redhat.com> <88e5f61f-253d-5e2a-a0bd-39beff55c82c@linaro.org> <87pmezztah.fsf@oldenburg.str.redhat.com> <47b750c6-f05c-2538-114d-3799628ebf56@linaro.org> <87zgdqd7zx.fsf@oldenburg.str.redhat.com> Date: Thu, 20 Oct 2022 18:40:41 -0700 From: Rain To: "Florian Weimer" , "Adhemerval Zanella Netto" Cc: "Christian Brauner" , "Adhemerval Zanella Netto via Libc-help" Subject: Re: posix_spawn: parent can get stuck in uninterruptible sleep if child receives SIGTSTP early enough Content-Type: text/plain X-Spam-Status: No, score=-3.2 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,JMQ_SPF_NEUTRAL,RCVD_IN_DNSWL_LOW,SPF_HELO_PASS,SPF_PASS,TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: On Thu, Oct 20, 2022, at 04:55, Florian Weimer wrote: > * Adhemerval Zanella Netto: > >>> I don't think switching back to fork by default is really an option. >>> The impact on latency is much worse than with vfork. >> >> I agree and I have been chatting with Christian if we can improve this >> with some kernel support. My idea would to add a new clone3 argument >> to define a signal mask and another options (either through clone3 >> itself or with a new execve variant) to setup the desired signal mask >> after execve call. >> >> The first features is more an optimization to avoid the sigprocmask >> (although I think we will need it anyway to proper reap the child if >> the spawni fails), while the second feature should fix the issue >> raised in this thread. > > But I think it would only work for SIGTSTP, not for SIGSTOP, right? > But maybe SIGSTOP is sufficiently unusual that fixing SIGTSP on its own > is already a welcome improvement. >From my perspective, fixing SIGTSTP is enough. However, I do care about older versions of the Linux kernel and glibc, as well as other operating systems, so I'll probably have to maintain the double-process-spawn workaround indefinitely, sadly. Thanks, Rain