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 411EBC433EF for ; Wed, 6 Apr 2022 01:00:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1838783AbiDFA4x (ORCPT ); Tue, 5 Apr 2022 20:56:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33850 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1385155AbiDEMbf (ORCPT ); Tue, 5 Apr 2022 08:31:35 -0400 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 090C87DE1A for ; Tue, 5 Apr 2022 04:45:50 -0700 (PDT) Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out1.suse.de (Postfix) with ESMTP id 99DBD210E5; Tue, 5 Apr 2022 11:45:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1649159149; 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=T2+2DI4PJUlQeQ3bPjloIZWijphTujPw/rrjaz7/Ejs=; b=ghtHkB4Oe3/PPKVMfeSxtiRqyttn4srt4dPMqKfup4sys6+1pALw8SNp1pRxsbuNgfa2U1 za2xH+BJM6ssCQ5jl1aKQwmnkGePjjYuRUxUYNmBkyg3kUv/7Yviozl12mPKkoWf4YWkfr yFpKJIYX1CUAzxHqmSdGe/Mjx9kU8pY= Received: from suse.cz (unknown [10.100.201.86]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by relay2.suse.de (Postfix) with ESMTPS id 86893A3B87; Tue, 5 Apr 2022 11:45:48 +0000 (UTC) Date: Tue, 5 Apr 2022 13:45:48 +0200 From: Michal Hocko To: Alexander Sverdlin Cc: Nicholas Piggin , Alexander Duyck , Matthew Wilcox , Hugh Dickins , Yu Zhao , Mel Gorman , Lee Schermerhorn , Sasha Levin , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: mm: swap: locking in release_pages() Message-ID: References: <89009285-c75d-0f09-5b08-d133c42a18f9@nokia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue 05-04-22 13:36:09, Alexander Sverdlin wrote: > Hello Michal, > > thanks for the quick reply! > > On 05/04/2022 12:43, Michal Hocko wrote: > >> 1. Crash of v5.4.170 on an ARM32 machine: > >> > >> Unable to handle kernel NULL pointer dereference at virtual address 00000104 > >> pgd = e138149d > >> [00000104] *pgd=84d2fd003, *pmd=8ffd6f003 > >> Internal error: Oops: a07 [#1] PREEMPT SMP ARM > >> ... > >> CPU: 1 PID: 6172 Comm: AaSysInfoRColle Tainted: G B O 5.4.170-... #1 > >> Hardware name: Keystone > >> PC is at release_pages+0x194/0x358 > >> LR is at release_pages+0x10c/0x358 > > Which LOC does this correspond to? (faddr2line should give you a nice > > output). > > Sorry, I forgot this info in the initial report: > > this is indeed the del_page_from_lru_list() in this crash. Could you be more specific please? Is the problem in list_del or update_lru_size? -- Michal Hocko SUSE Labs