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=-4.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 5E737C433E1 for ; Tue, 21 Jul 2020 02:54:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 338B82077D for ; Tue, 21 Jul 2020 02:54:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="g2GpQouO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728105AbgGUCyz (ORCPT ); Mon, 20 Jul 2020 22:54:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58206 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725857AbgGUCyy (ORCPT ); Mon, 20 Jul 2020 22:54:54 -0400 Received: from mail-pl1-x641.google.com (mail-pl1-x641.google.com [IPv6:2607:f8b0:4864:20::641]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 55F38C061794 for ; Mon, 20 Jul 2020 19:54:54 -0700 (PDT) Received: by mail-pl1-x641.google.com with SMTP id 72so9606323ple.0 for ; Mon, 20 Jul 2020 19:54:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=z2RSfMnvW+syz3YOB+XHzd61RaRTKVl0CYaYMTeo2IM=; b=g2GpQouOZ0by46nzuuPXea+3qTk65JlELWYwrLcFira2dq1gxPskSRkGhgMXt+ExwO +awvuQyhVyzF9/xfYXWP9qyv+dZP5JStWkJeREbMr+TyyiBYb7wB5l5b1hQxxK/gCo+s 2rgtqIRk4yQLfYd6dD0AxGOpscqE+7C5j2qas5SATLGP5OupzS/9ulh8XFKb3o3DipBv b44Lio6mR/B1vVtuuQtvb2wuzxvJisY4s4SDsdNz0l6DsFi9DL2Ha2RPrBcftIEZEZ3E EjXoZpgThsglU6ku+Q7JgJiyotqa8Ipu0ILPJdHhOxRBgKn+n/vhtGyQC7My9vw5YYnk ncVA== 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:references :mime-version:content-disposition:in-reply-to; bh=z2RSfMnvW+syz3YOB+XHzd61RaRTKVl0CYaYMTeo2IM=; b=X7Q6mo4YC2229SeSBqKAzlIlsONEe8LhDy2iMZQjPSl58vF9ARYfiCmmaA/8GOuoMI cySkVq2YZGg+sCjzF5PX8V69Na/6X+9N08C12ajA3dl3P10ujz8/MtXD/y7VKck5JkoK 6we3LhkfqnyiFOonxSUwX7YfGUumXpJVIGxmF13GtjaSFeELArxx4ZbFxuzjlslHH39R zWvdjTQjARWuB2ARc5ETcckNPQPgCTl6+tTGnMXEAss3tNIsBdNm2vaLU4kuDCGej1yZ DD/I1Ei0zQNnrXUdR5LV8qQ9BJYA9WUVbljQymjDHC8N2zlkxSujRpPerWXnJf8xUeqx T+2g== X-Gm-Message-State: AOAM533gP9b+FFMC3PlCHV2E3b3BlG6q7a6BhjhIn+6cDBNnB9BCuc6s 0DDBu90HNTaLIhuOpBk3d7U= X-Google-Smtp-Source: ABdhPJwWbe6de+I3xkaE1Q3ZDm3nbXKT4+42Pk8apBXAvEa0eBHeueusDPk90W9rlpPugT0jDs8CWw== X-Received: by 2002:a17:902:ff10:: with SMTP id f16mr20624644plj.277.1595300093875; Mon, 20 Jul 2020 19:54:53 -0700 (PDT) Received: from localhost ([2409:10:2e40:5100:6e29:95ff:fe2d:8f34]) by smtp.gmail.com with ESMTPSA id m26sm18223314pff.84.2020.07.20.19.54.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 20 Jul 2020 19:54:53 -0700 (PDT) Date: Tue, 21 Jul 2020 11:54:50 +0900 From: Sergey Senozhatsky To: John Ogness Cc: Petr Mladek , Sergey Senozhatsky , Sergey Senozhatsky , Steven Rostedt , Linus Torvalds , Greg Kroah-Hartman , Peter Zijlstra , Thomas Gleixner , Marco Elver , kexec@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH][next] printk: ringbuffer: support dataless records Message-ID: <20200721025450.GA5678@jagdpanzerIV.localdomain> References: <20200720140111.19935-1-john.ogness@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200720140111.19935-1-john.ogness@linutronix.de> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (20/07/20 16:07), John Ogness wrote: > > +/* Determine if a logical position refers to a data-less block. */ > +#define LPOS_DATALESS(lpos) ((lpos) & 1UL) > + [..] > @@ -1402,7 +1396,9 @@ static int prb_read(struct printk_ringbuffer *rb, u64 seq, > /* Copy text data. If it fails, this is a data-less record. */ > if (!copy_data(&rb->text_data_ring, &desc.text_blk_lpos, desc.info.text_len, > r->text_buf, r->text_buf_size, line_count)) { > - return -ENOENT; > + /* Report an error if there should have been data. */ > + if (desc.info.text_len != 0) > + return -ENOENT; > } If this is a dataless record then should copy_data() return error? Otherwise, looks good to me Acked-by: Sergey Senozhatsky -ss