From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf1-f198.google.com (mail-pf1-f198.google.com [209.85.210.198]) by kanga.kvack.org (Postfix) with ESMTP id C08C68E0001 for ; Wed, 19 Dec 2018 12:36:38 -0500 (EST) Received: by mail-pf1-f198.google.com with SMTP id t72so18997787pfi.21 for ; Wed, 19 Dec 2018 09:36:38 -0800 (PST) Received: from smtprelay.synopsys.com (us01smtprelay-2.synopsys.com. [198.182.60.111]) by mx.google.com with ESMTPS id d189si17530719pfa.70.2018.12.19.09.36.36 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 19 Dec 2018 09:36:37 -0800 (PST) From: Vineet Gupta Subject: Re: [PATCH 1/2] ARC: show_regs: avoid page allocator Date: Wed, 19 Dec 2018 17:36:35 +0000 Message-ID: References: <1545159239-30628-1-git-send-email-vgupta@synopsys.com> <1545159239-30628-2-git-send-email-vgupta@synopsys.com> <1545239047.14089.13.camel@synopsys.com> Content-Language: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: owner-linux-mm@kvack.org List-ID: To: Eugeniy Paltsev , "linux-snps-arc@lists.infradead.org" Cc: "linux-arch@vger.kernel.org" , "linux-mm@kvack.org" , "peterz@infradead.org" , "linux-kernel@vger.kernel.org" On 12/19/18 9:04 AM, Eugeniy Paltsev wrote:=0A= > Just curious: isn't that enough to use GFP_NOWAIT instead=0A= > of GFP_KERNEL when we allocate page in show_regs()?=0A= >=0A= > As I can see x86 use print_vma_addr() in their show_signal_msg()=0A= > function which allocate page with __get_free_page(GFP_NOWAIT);=0A= =0A= I'm not sure if lockdep will be happy with it still.=0A= =0A= At any rate, as explained in changelog, this still has merit, since the buf= fer is=0A= only needed for nested d_path calls, which are better served with a smaller= =0A= on-stack buffer. For cases such as kernel crash, we want lesser code/traces= in=0A= fault path to sift thru !=0A= =0A= -Vineet=0A=