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[2620:137:e000::1:20]) by mx.google.com with ESMTP id h7-20020a170906530700b006f3b19b0bb9si11195667ejo.89.2022.06.19.22.12.20; Sun, 19 Jun 2022 22:13:01 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=casper.20170209 header.b=O2Mz1eTE; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238035AbiFTEy4 (ORCPT + 99 others); Mon, 20 Jun 2022 00:54:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37870 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233817AbiFTEyz (ORCPT ); Mon, 20 Jun 2022 00:54:55 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 72A7FDEB5 for ; Sun, 19 Jun 2022 21:54:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=j30w33pgKvnkmiJ8DHGQfIQa6b/GR+VvA+wwmWWYK7E=; b=O2Mz1eTEa1YyqV2pwYjciVC6Ar OPnfdVrsHZk+V0zKt7DQys+D5CF+U4oJ3lXxZIokHK6DTDVMCruAg9U4hdqtq6fb2kR7X7C7HhiIC qW6gEEie9tDL1Xqk9au/p6lSkP546hglKd8ESKyEN2cgk7qL8mrlUICPzWldciRfQqWxOctuxKNSH kndVFTo93k9kRQ1iLyD0s3ZNs9YLjeiJyN0SKGXvKSw6tjTydG6LqM6Z0mUu7S/Y1FZEUne+usQM7 thjX8lz0NebgrIrbyhE3+uHjR+KiTTTxOvDfKlV16di0qyb7OopMtQ5JVRah8sfxstCNWXNh5HLJG PkAQ6DbQ==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1o39R2-004sEZ-P9; Mon, 20 Jun 2022 04:54:48 +0000 Date: Mon, 20 Jun 2022 05:54:48 +0100 From: Matthew Wilcox To: David Laight Cc: 'Kent Overstreet' , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "pmladek@suse.com" , "rostedt@goodmis.org" , "enozhatsky@chromium.org" , "linux@rasmusvillemoes.dk" Subject: Re: [PATCH v4 00/34] Printbufs - new data structure for building strings Message-ID: References: <20220620004233.3805-1-kent.overstreet@gmail.com> <0a5901f8460f452a89c9b0cda32fb833@AcuMS.aculab.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <0a5901f8460f452a89c9b0cda32fb833@AcuMS.aculab.com> X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED,SPF_HELO_NONE, SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 20, 2022 at 04:19:31AM +0000, David Laight wrote: > I really think that is a bad idea. > printk() already uses a lot of stack, anything doing a recursive > call is just making that worse. > Especially since these calls can often be in error paths > which are not often tested and can already be on deep stacks. You made this complaint last time and I challenged you to provide data. You have not, as yet, provided data.