From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A7060C10F26 for ; Sat, 7 Mar 2020 13:11:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7F8F02075A for ; Sat, 7 Mar 2020 13:11:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=mvista-com.20150623.gappssmtp.com header.i=@mvista-com.20150623.gappssmtp.com header.b="1/8MHk1O" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726296AbgCGNLl (ORCPT ); Sat, 7 Mar 2020 08:11:41 -0500 Received: from mail-ot1-f67.google.com ([209.85.210.67]:42215 "EHLO mail-ot1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726105AbgCGNLk (ORCPT ); Sat, 7 Mar 2020 08:11:40 -0500 Received: by mail-ot1-f67.google.com with SMTP id 66so5201933otd.9 for ; Sat, 07 Mar 2020 05:11:40 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mvista-com.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:reply-to:references:mime-version :content-disposition:in-reply-to:user-agent; bh=J4p6CveRCCmA2UOrY+JX/CiuZIW93/gthzgtABNAuu0=; b=1/8MHk1O7FLY17YfXkC+nkMhj/pCDJQDaSXUX3nfjZ1VOTf+nyTAaJ94as4sPG+vXr zJ9Si1xqkRV0mX+f5k4aUstJVHiepuZEySL0zb5J9DL637dw+n2a7ESC4rZQExO6JHvv pX9L9QK2ZK/RH2ifCDy6iDNFzjzJlATTZggA0B7XFPGtGJeZwfx+k2O3dDCLsTmb1BcO Ouu5GQfqwz1hrDPc49OJedXO6nX5k1FkMHOHRe4VSUBxtC7ZU77g9hqsjqbL1FmVt0fz 9QvSntzQky3OydY0/jyw4KxCShAH+cCEBY+af6bHZvkfiIVI6sR9iMG0W2kdv5WB+GhO jk5Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:reply-to :references:mime-version:content-disposition:in-reply-to:user-agent; bh=J4p6CveRCCmA2UOrY+JX/CiuZIW93/gthzgtABNAuu0=; b=gI2jSv+5DgdsuQWP9mpyWj4vfz16Fw5T0J0EBhcu/G+KpaQ7ewTE96Aytda3c6RfZb gUH3lAhkt8LQrsxZbn8p9N2ejuFI7S4Mcide6PwDDvofrGyFvG7sliHdwFzdI/NScDnB h3960m7r56sUSr3A3gnTlkueB70/JurI5q45ZmBPwHZHbduPBFEdoUClIfRiCjQx7+EG LCw9MWLD/ZgbILeA7DUlbz8I0o9oS7m7JOgGlbZyytTp+rUHeHdje3dSbWHr+VzDf/OZ YyYA7cVClnB5v0KKcW0Gwcr4l3Ek6JaLKJUuGPkn0ybYTMnZWVQbKY4l12otXv8WPz/e Z4qg== X-Gm-Message-State: ANhLgQ17MyDBWuc0ZR9ubBlMRqvOkMV5YkoqrytXXBb4JxpeTcvyj/vE OiCRt7gIcgk8pF/+XN5/sm0w3A== X-Google-Smtp-Source: ADFU+vvVyZPXSmAxtQpvvaio/rX9SrEtO/27S7Qk9r3r3pkTzRT5RxNkJ+ip1g+0uhhEcY4rhK06VA== X-Received: by 2002:a9d:7cd4:: with SMTP id r20mr6434214otn.148.1583586699738; Sat, 07 Mar 2020 05:11:39 -0800 (PST) Received: from minyard.net ([2001:470:b8f6:1b:a549:b51b:bece:c41b]) by smtp.gmail.com with ESMTPSA id o1sm12475012otl.49.2020.03.07.05.11.38 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Sat, 07 Mar 2020 05:11:38 -0800 (PST) Date: Sat, 7 Mar 2020 07:11:36 -0600 From: Corey Minyard To: Christian Brauner Cc: minyard@acm.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, Adrian Reber , Oleg Nesterov , Dmitry Safonov <0x7f454c46@gmail.com>, Andrei Vagin Subject: Re: [PATCH v2] pid: Fix error return value in some cases Message-ID: <20200307131136.GD2847@minyard.net> Reply-To: cminyard@mvista.com References: <20200306172314.12232-1-minyard@acm.org> <20200307110007.fmtaaqt2udsgohtp@wittgenstein> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200307110007.fmtaaqt2udsgohtp@wittgenstein> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Mar 07, 2020 at 12:00:07PM +0100, Christian Brauner wrote: > On Fri, Mar 06, 2020 at 11:23:14AM -0600, minyard@acm.org wrote: > > From: Corey Minyard > > > > Recent changes to alloc_pid() allow the pid number to be specified on > > the command line. If set_tid_size is set, then the code scanning the > > levels will hard-set retval to -EPERM, overriding it's previous -ENOMEM > > value. > > > > After the code scanning the levels, there are error returns that do not > > set retval, assuming it is still set to -ENOMEM. > > > > So set retval back to -ENOMEM after scanning the levels. > > > > Fixes: 49cb2fc42ce4 "fork: extend clone3() to support setting a PID" > > Signed-off-by: Corey Minyard > > Cc: # 5.5 > > Cc: Adrian Reber > > Cc: Christian Brauner > > Cc: Oleg Nesterov > > Cc: Dmitry Safonov <0x7f454c46@gmail.com> > > Cc: Andrei Vagin > > Thanks! I've pulled the patch now and applied. > > I think that restores the old behavior. If you don't mind, I'll add a > comment on top of it saying something like: > "ENOMEM is not the most obvious choice but it's the what we've been > exposing to userspace for a long time and it's also documented > behavior. So we can't easily change it to something more sensible." That's great. I was just looking through the code for another reason and noticed the issue. Every little thing counts for quality. -corey > > Acked-by: Christian Brauner