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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2D243C04A94 for ; Fri, 4 Aug 2023 07:51:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234063AbjHDHvK (ORCPT ); Fri, 4 Aug 2023 03:51:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42992 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233795AbjHDHvE (ORCPT ); Fri, 4 Aug 2023 03:51:04 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [IPv6:2001:67c:2178:6::1d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EC0A34234 for ; Fri, 4 Aug 2023 00:51:01 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 461081F749; Fri, 4 Aug 2023 07:51:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1691135460; h=from:from:reply-to: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=vjm5wLyvz4cY9tLarxXb4REzVGSm0jQGJmCuVtpqVdo=; b=fLkVdr8WXOyDzySmPvkVnK1GAmb5vqHMQHl8cyod1jYgQmhu/eshedwFHp05bvZ1LB1kRF dNEHhlHk620xBke/GpFs5J5gT3Q+QJkC6Bz1EM6uQiV/fWhnMG628zBaGm1YjfoJFTTiYX KbUkxTDTnLudRfJMVggZl0e77iDqq9w= Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 26AB913904; Fri, 4 Aug 2023 07:51:00 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id JWX2BuStzGRtZQAAMHmgww (envelope-from ); Fri, 04 Aug 2023 07:51:00 +0000 Date: Fri, 4 Aug 2023 09:50:59 +0200 From: Michal Hocko To: Douglas Anderson Cc: Andrew Morton , Petr Mladek , kernel test robot , Lecopzer Chen , Pingfan Liu , linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 2/2] watchdog/hardlockup: Avoid large stack frames in watchdog_hardlockup_check() Message-ID: References: <20230803160649.v3.1.Ia35521b91fc781368945161d7b28538f9996c182@changeid> <20230803160649.v3.2.I501ab68cb926ee33a7c87e063d207abf09b9943c@changeid> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230803160649.v3.2.I501ab68cb926ee33a7c87e063d207abf09b9943c@changeid> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 03-08-23 16:07:58, Douglas Anderson wrote: > After commit 77c12fc95980 ("watchdog/hardlockup: add a "cpu" param to > watchdog_hardlockup_check()") we started storing a `struct cpumask` on > the stack in watchdog_hardlockup_check(). On systems with > CONFIG_NR_CPUS set to 8192 this takes up 1K on the stack. That > triggers warnings with `CONFIG_FRAME_WARN` set to 1024. > > We'll use the new trigger_allbutcpu_cpu_backtrace() to avoid needing > to use a CPU mask at all. > > Fixes: 77c12fc95980 ("watchdog/hardlockup: add a "cpu" param to watchdog_hardlockup_check()") > Reported-by: kernel test robot > Closes: https://lore.kernel.org/r/202307310955.pLZDhpnl-lkp@intel.com > Signed-off-by: Douglas Anderson Acked-by: Michal Hocko Thanks! -- Michal Hocko SUSE Labs