From owner-svn-src-all@freebsd.org Tue Sep 22 21:50:43 2020 Return-Path: Delivered-To: svn-src-all@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 0FB0E3E0C7B for ; Tue, 22 Sep 2020 21:50:43 +0000 (UTC) (envelope-from wlosh@bsdimp.com) Received: from mail-lj1-x22f.google.com (mail-lj1-x22f.google.com [IPv6:2a00:1450:4864:20::22f]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "smtp.gmail.com", Issuer "GTS CA 1O1" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4Bww3Q2MwTz3TbH for ; Tue, 22 Sep 2020 21:50:42 +0000 (UTC) (envelope-from wlosh@bsdimp.com) Received: by mail-lj1-x22f.google.com with SMTP id y4so15423964ljk.8 for ; Tue, 22 Sep 2020 14:50:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bsdimp-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=XOwBsK4LJIB/Noe1hwndd/rUz3qsAYh1KJM2Ku11QfQ=; b=egCh3mi6iodLQDhDX6Y/20456jqBXtnJlqdEk3O/BemZTgImhbRNOSLChsyfRRGju5 a9AbfDuU9hNskvFXQGeuftqaMFz56oc+UIb+Q9R4DXtgIjibiOO4UkU1aNKpRtlUj86N aBsCrz6pJhMIE8jGFI0XxYcSiuWrewD7HQqTot/V3N5RQ3aGAOmbOdZ7iRn3vQpGFzFF CzBZDaOe02d4reciO/q4stPfKdXKNLM9XOu6XkbV2k0sKV8ec5wdXhNYk2pwY1xLkmWK 4+jiQ1ysfJm85omREE+BTRVMA4zM2YwDGKXD8L2uCadVSKChxxbeKT7077m40cTHYMTH 1wQg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=XOwBsK4LJIB/Noe1hwndd/rUz3qsAYh1KJM2Ku11QfQ=; b=A6LTrBstHXtiL7fpxHRbj6/TAFRfPpYPGmuGShnjGrmMZdWiUTa3PrGmuK3Xw8Mwxj krNLJ5C1YjPKX7mjMadHOWkDFRQ7Qw8dgyLr4la896xQ6Ys4neqQOV3UQEi8Ui6QV7WH xVLIwqv4xCUOdf9Dd5HReXNhISXU4AqDGmutLB6tZ7qKwhNQk6Uznf++F4TlGD2gg4gI Imo8cxaea6N2n7YD0rL8t2kTZUYFC7uzU+vEUFDbz8K2F/a+dcfbTXeEfPLQvD6NPo0m bxao89CJpjj7BGBVkgflUzI00kqRJKGUvy1cL8jr8yaihsS8DzLMWYJq4uCoTUhvFj97 l3mA== X-Gm-Message-State: AOAM5301zhns4aVGgp/TjpnmgBy0qz/aUWseIiIWhxsQ97IO9HZV1YMR V9LAnpFklBmlpJC/L0IeVWsWKFosrRXb9xPq8XIAJg== X-Google-Smtp-Source: ABdhPJxOeuWwIupNg1o9RUyN14YBsepnCsEF6hsKDEGslTDN9XzKdoQPlgqJWyfRUAG0dbii3DEkhNGqL4E6c/ljV6I= X-Received: by 2002:a2e:8898:: with SMTP id k24mr1987672lji.74.1600811440384; Tue, 22 Sep 2020 14:50:40 -0700 (PDT) MIME-Version: 1.0 References: <202009112049.08BKnavL032212@repo.freebsd.org> In-Reply-To: From: Warner Losh Date: Tue, 22 Sep 2020 15:50:29 -0600 Message-ID: Subject: Re: svn commit: r365643 - head/bin/cp To: Alan Somers Cc: Kyle Evans , Mateusz Guzik , src-committers , svn-src-all , svn-src-head X-Rspamd-Queue-Id: 4Bww3Q2MwTz3TbH X-Spamd-Bar: - Authentication-Results: mx1.freebsd.org; dkim=pass header.d=bsdimp-com.20150623.gappssmtp.com header.s=20150623 header.b=egCh3mi6; dmarc=none; spf=none (mx1.freebsd.org: domain of wlosh@bsdimp.com has no SPF policy when checking 2a00:1450:4864:20::22f) smtp.mailfrom=wlosh@bsdimp.com X-Spamd-Result: default: False [-1.57 / 15.00]; RCVD_TLS_ALL(0.00)[]; ARC_NA(0.00)[]; R_DKIM_ALLOW(-0.20)[bsdimp-com.20150623.gappssmtp.com:s=20150623]; NEURAL_HAM_MEDIUM(-0.91)[-0.908]; FROM_HAS_DN(0.00)[]; FREEMAIL_CC(0.00)[freebsd.org,gmail.com]; NEURAL_HAM_LONG(-0.98)[-0.975]; MIME_GOOD(-0.10)[multipart/alternative,text/plain]; PREVIOUSLY_DELIVERED(0.00)[svn-src-all@freebsd.org]; DMARC_NA(0.00)[bsdimp.com]; RCPT_COUNT_FIVE(0.00)[6]; TO_MATCH_ENVRCPT_SOME(0.00)[]; TO_DN_ALL(0.00)[]; DKIM_TRACE(0.00)[bsdimp-com.20150623.gappssmtp.com:+]; RCVD_IN_DNSWL_NONE(0.00)[2a00:1450:4864:20::22f:from]; NEURAL_SPAM_SHORT(0.31)[0.311]; R_SPF_NA(0.00)[no SPF record]; FORGED_SENDER(0.30)[imp@bsdimp.com,wlosh@bsdimp.com]; MIME_TRACE(0.00)[0:+,1:+,2:~]; RCVD_COUNT_TWO(0.00)[2]; ASN(0.00)[asn:15169, ipnet:2a00:1450::/32, country:US]; FROM_NEQ_ENVFROM(0.00)[imp@bsdimp.com,wlosh@bsdimp.com]; MAILMAN_DEST(0.00)[svn-src-all] Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.33 X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.33 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 22 Sep 2020 21:50:43 -0000 I think it's a great leap sideways, but I've done cp /dev/null foo to clear it out for 35 years now... It's why it feels like a workaround. Though it is a legit optimization, no matter the feelings. As for clearer, I'm less sure since then I have to remember what the : operator does. Warner On Tue, Sep 22, 2020 at 3:48 PM Alan Somers wrote: > It doesn't feel like a workaround to me. I think Kyle's version is > clearer than the original. > > On Tue, Sep 22, 2020 at 3:45 PM Warner Losh wrote: > >> >> >> On Tue, Sep 22, 2020 at 3:42 PM Kyle Evans wrote: >> >>> cp is already fixed, people are still feeling the fallout of being >>> within those revisions and needing to bootstrap their own cp. We can >>> reduce the number of components these invocations rely on trivially to >>> shell built-in mechanics, why not do so? >>> >> >> Fair point. I just bristle at putting workarounds in for valid /bin/sh >> syntax because we opposed for a few days. so long as it's an unconditional >> clearing of the file to be zero length, I'm OK with that. >> >> Warner >> >> >>> On Tue, Sep 22, 2020 at 4:40 PM Warner Losh wrote: >>> > >>> > So why do we need a workaround at all? cp /dev/null has been fixed, >>> and that's way more important to get right. >>> > >>> > I don't want to paper-over issues with this at all, though if we use >>> the host's (now broken) cp, I suppose that might be OK in the short term. >>> If that's the case, then maybe this is OK. >>> > >>> > Otherwise, I'd strongly prefer we fix cp. >>> > >>> > Warner >>> > >>> > On Tue, Sep 22, 2020 at 3:31 PM Alan Somers >>> wrote: >>> >> >>> >> +1. >>> >> >>> >> On Tue, Sep 22, 2020 at 3:27 PM Kyle Evans >>> wrote: >>> >>> >>> >>> I'm running a build at the suggestion of mjg to confirm there aren't >>> >>> any others hiding that can be converted, and I will commit after I've >>> >>> verified that this is it. >>> >>> >>> >>> On Tue, Sep 22, 2020 at 4:02 PM Alan Somers >>> wrote: >>> >>> > >>> >>> > LGTM. >>> >>> > >>> >>> > On Tue, Sep 22, 2020 at 2:59 PM Kyle Evans >>> wrote: >>> >>> >> >>> >>> >> Perhaps: >>> >>> >> >>> >>> >> diff --git a/stand/i386/zfsboot/Makefile >>> b/stand/i386/zfsboot/Makefile >>> >>> >> index ff315abc0ef..7e362b43a39 100644 >>> >>> >> --- a/stand/i386/zfsboot/Makefile >>> >>> >> +++ b/stand/i386/zfsboot/Makefile >>> >>> >> @@ -81,7 +81,7 @@ zfsboot.ld: zfsboot.ldr zfsboot.bin ${BTXKERN} >>> >>> >> -o ${.TARGET} -P 1 zfsboot.bin >>> >>> >> >>> >>> >> zfsboot.ldr: >>> >>> >> - cp /dev/null ${.TARGET} >>> >>> >> + :> ${.TARGET} >>> >>> >> >>> >>> >> zfsboot.bin: zfsboot.out >>> >>> >> ${OBJCOPY} -S -O binary zfsboot.out ${.TARGET} >>> >>> >> diff --git a/stand/libsa/Makefile b/stand/libsa/Makefile >>> >>> >> index effece9e01b..63cd46a9c54 100644 >>> >>> >> --- a/stand/libsa/Makefile >>> >>> >> +++ b/stand/libsa/Makefile >>> >>> >> @@ -122,7 +122,7 @@ beforedepend: >>> >>> >> ln -sf ${SRCTOP}/include/arpa/inet.h arpa/inet.h; \ >>> >>> >> ln -sf ${SRCTOP}/include/arpa/tftp.h arpa/tftp.h; \ >>> >>> >> for i in _time.h _strings.h _string.h; do \ >>> >>> >> - [ -f xlocale/$$i ] || cp /dev/null xlocale/$$i; \ >>> >>> >> + [ -f xlocale/$$i ] || :> xlocale/$$i; \ >>> >>> >> done; \ >>> >>> >> for i in ${STAND_H_INC}; do \ >>> >>> >> ln -sf ${SASRC}/stand.h $$i; \ >>> >>> >> >>> >>> >> >>> >>> >> On Tue, Sep 22, 2020 at 3:58 PM Alan Somers >>> wrote: >>> >>> >> > >>> >>> >> > Looks like two places in stand. Is there any reason why >>> Mateusz's suggestion wouldn't work? >>> >>> >> > >>> >>> >> > > rg -g Makefile 'cp.*/dev/null' >>> >>> >> > stand/libsa/Makefile >>> >>> >> > 125: [ -f xlocale/$$i ] || cp /dev/null xlocale/$$i; \ >>> >>> >> > >>> >>> >> > stand/i386/zfsboot/Makefile >>> >>> >> > 82: cp /dev/null ${.TARGET} >>> >>> >> > >>> >>> >> > On Tue, Sep 22, 2020 at 2:54 PM Mateusz Guzik < >>> mjguzik@gmail.com> wrote: >>> >>> >> >> >>> >>> >> >> Can we instead add a workaround to the build tree? >>> >>> >> >> >>> >>> >> >> Where is cp /dev/null coming from anyway? Perhaps this can be >>> patched >>> >>> >> >> to touch the target file. >>> >>> >> >> >>> >>> >> >> On 9/22/20, Alan Somers wrote: >>> >>> >> >> > On Tue, Sep 22, 2020 at 2:48 PM Kyle Evans < >>> kevans@freebsd.org> wrote: >>> >>> >> >> > >>> >>> >> >> >> On Fri, Sep 11, 2020 at 3:49 PM Alan Somers < >>> asomers@freebsd.org> wrote: >>> >>> >> >> >> > >>> >>> >> >> >> > Author: asomers >>> >>> >> >> >> > Date: Fri Sep 11 20:49:36 2020 >>> >>> >> >> >> > New Revision: 365643 >>> >>> >> >> >> > URL: https://svnweb.freebsd.org/changeset/base/365643 >>> >>> >> >> >> > >>> >>> >> >> >> > Log: >>> >>> >> >> >> > cp: fall back to read/write if copy_file_range fails >>> >>> >> >> >> > >>> >>> >> >> >> > Even though copy_file_range has a file-system agnostic >>> version, it >>> >>> >> >> >> still >>> >>> >> >> >> > fails on devfs (perhaps because the file descriptor is >>> non-seekable?) >>> >>> >> >> >> In >>> >>> >> >> >> > that case, fallback to old-fashioned read/write. Fixes >>> >>> >> >> >> > "cp /dev/null /tmp/null" >>> >>> >> >> >> > >>> >>> >> >> >> >>> >>> >> >> >> Hi, >>> >>> >> >> >> >>> >>> >> >> >> Any objection to adding a quick UPDATING entry for this? >>> I'm seeing >>> >>> >> >> >> occasional reports of this breakage as recent as today on >>> IRC from >>> >>> >> >> >> folks that were a little bit thrown off by this because it >>> throws up >>> >>> >> >> >> fairly far into the build and looks like a stand build >>> regression >>> >>> >> >> >> instead of a cp regression. >>> >>> >> >> >> >>> >>> >> >> >> Thanks, >>> >>> >> >> >> >>> >>> >> >> >> Kyle Evans >>> >>> >> >> >> >>> >>> >> >> > >>> >>> >> >> > No objection. Can you suggest the proper wording? >>> >>> >> >> > _______________________________________________ >>> >>> >> >> > svn-src-all@freebsd.org mailing list >>> >>> >> >> > https://lists.freebsd.org/mailman/listinfo/svn-src-all >>> >>> >> >> > To unsubscribe, send any mail to " >>> svn-src-all-unsubscribe@freebsd.org" >>> >>> >> >> > >>> >>> >> >> >>> >>> >> >> >>> >>> >> >> -- >>> >>> >> >> Mateusz Guzik >>> >>