From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 52E7F19BA2 for ; Sat, 27 Jan 2024 21:11:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706389894; cv=none; b=RnnH61py0m3CGshehAHL6v8oz667mhI7jjvmTHtZOsQd98ZcY+vXCoKPYzHymqOQaLbG8BsKxBKwpo3buKzPhxC5TyvfPp2Xi25H5OcUVOc5GcwcGWXorMvCa/vYBt/BBufT4WU+4T1IKePfPuKkc9NJxqQAaNwhrqQs9cpMwtE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706389894; c=relaxed/simple; bh=e9ssbtj5/gqXRUdezTmszQ5A3hRAEynVyD59GYaJgEc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=WJS8Lqno7OXQIPCPKyMPl+WmsUUyux34L2QJDW3q3JcfpPFB+nlnnc97TSHEJ+KRxj1ZF7t9n7NRv1UteRQ5LZyMQAwiZk4pFpwjVH462xG5FLmnePI7RNH0/kZ8EXjDypG5suHrtEhtap8PAdR/PlEOek+lEeAMCUuc2iqE/Po= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=hOgzVJxC; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="hOgzVJxC" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1706389891; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=RxDG8FbkrxGkzjJwUDG8WjeC4k+DKoBsMZSfq3CWFgY=; b=hOgzVJxCuPWI9wQ8IoS3JpVRkKuIjXAx7EHWEa0FADjgKZFnTtwWYTq9mMfoqxw2aTb16/ I62dDoo89iwKP9EONMdRdk5H9agAnb8ao8S/72mHMvEQDtc12Fo5C2yc83QTA1XzkUnVHh ktDg8Xs+bP2vstIci7/MvkwU/ragofs= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-13-GEniBBKxMF2e41sgRC3b0w-1; Sat, 27 Jan 2024 16:11:29 -0500 X-MC-Unique: GEniBBKxMF2e41sgRC3b0w-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 150571013768; Sat, 27 Jan 2024 21:11:29 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.45.224.37]) by smtp.corp.redhat.com (Postfix) with SMTP id A1C5E1121306; Sat, 27 Jan 2024 21:11:27 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Sat, 27 Jan 2024 22:10:14 +0100 (CET) Date: Sat, 27 Jan 2024 22:10:12 +0100 From: Oleg Nesterov To: Tycho Andersen Cc: Christian Brauner , linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, Tycho Andersen , "Eric W. Biederman" Subject: Re: [PATCH v3 1/3] pidfd: allow pidfd_open() on non-thread-group leaders Message-ID: <20240127210634.GE13787@redhat.com> References: <20240123195608.GB9978@redhat.com> <20240125140830.GA5513@redhat.com> <20240127105410.GA13787@redhat.com> <20240127163117.GB13787@redhat.com> <20240127193127.GC13787@redhat.com> Precedence: bulk X-Mailing-List: linux-api@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.3 On 01/27, Tycho Andersen wrote: > > On Sat, Jan 27, 2024 at 08:31:27PM +0100, Oleg Nesterov wrote: > > > > On the second thought I am starting to understand your concern... > > > > Indeed, in this case -EBADF is technically correct but it can confuse > > the user which doesn't or can't know that this task/thread is exiting, > > because EBADF looks as if the "int fd" argument was wrong. > > > > Sorry I missed your point before. > > No worries. I realized it's not so hard to fix with your new > xxx_exited() helper from the PIDFD_THREAD patch, so maybe worth > cleaning up after all? OK, lets discuss this later. I'll (hopefully) send v2 on top of pidfd: cleanup the usage of __pidfd_prepare's flags pidfd: don't do_notify_pidfd() if !thread_group_empty() on Monday, will be busy tomorrow (family duties ;) Oleg.