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,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 8726AC433E1 for ; Wed, 15 Jul 2020 06:36:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 573E420663 for ; Wed, 15 Jul 2020 06:36:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594795005; bh=72SF09OiKWNVBX6ta9gVBnB9wY+l4ES/Y5ThiS2yDNk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=pUzaAnH9DBMEq8BMQB+kU2BBAF1Sol6Be0rnKXud348u2U+aT3zJymha1kJSj/7ZW mAVykjipnaa/HQprD/QKHpINwQwHr86jK8x35nYM+00UtW4cs7kxAVXWkMKvgkvNTL jiq2SSm9FBcL9wKZw0zDS70t+1g+hgpD19ytuBoM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728788AbgGOGgo (ORCPT ); Wed, 15 Jul 2020 02:36:44 -0400 Received: from mail-wm1-f67.google.com ([209.85.128.67]:54119 "EHLO mail-wm1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728170AbgGOGgn (ORCPT ); Wed, 15 Jul 2020 02:36:43 -0400 Received: by mail-wm1-f67.google.com with SMTP id j18so4154447wmi.3 for ; Tue, 14 Jul 2020 23:36:42 -0700 (PDT) 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=7/7YlCQQS4NfdI2cjoTLRwj8KZpvs8wrGSrY0FMkPh0=; b=auYB1ZrHE+hLA2QLYSMZCKP28XdnqsbplFy86fYIxJRVCIBanEKafGrrMGjI+iSzyU nPKmMReFyEoOIo/IDz3Slmj92b1n4eBTRZukc81zSw8pgOwmfRZbKWkB8blPniiZSksq QRwx45UBfyZx/EPQ3mSAadhAUc3MCdeSCzYrYMyjf4gll3aZLgm1PHBrlijoRzwsWd67 SV9PZjCSN2vVQwx3moQx5P77ZgfkRme8jlA23aM0LWi4ncb1jA6ovxHWOacMzkhEvrbf Qkb26bVeeHXWM7tSzrFlLXBCHGnar2bQ034bYsS76Z9c+/oeuoj/7CC1hPHR9r1LmWRC Fqug== X-Gm-Message-State: AOAM533XIZuLu6qAenkeL6OaaxiCM7WSl0E84LsQ/p9l4dH35aigkY6r Zp+3Gz/JmH1+S0+Po5E20Og= X-Google-Smtp-Source: ABdhPJzhsPV6nJJtiemGrmFxaPyOMI93M1GFQlk9i6/jxMDh1l1C4XRZG2kXT5m6ORa3FiYsr6xBRg== X-Received: by 2002:a7b:cf18:: with SMTP id l24mr7024055wmg.116.1594795001964; Tue, 14 Jul 2020 23:36:41 -0700 (PDT) Received: from localhost (ip-37-188-169-187.eurotel.cz. [37.188.169.187]) by smtp.gmail.com with ESMTPSA id u16sm1896668wmn.11.2020.07.14.23.36.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 14 Jul 2020 23:36:41 -0700 (PDT) Date: Wed, 15 Jul 2020 08:36:39 +0200 From: Michal Hocko To: Suren Baghdasaryan Cc: Todd Kjos , Hridya Valsaraju , Hillf Danton , Eric Biggers , syzbot , Andrew Morton , Arve =?iso-8859-1?B?SGr4bm5lduVn?= , Christian Brauner , "open list:ANDROID DRIVERS" , Greg Kroah-Hartman , Hugh Dickins , "Joel Fernandes (Google)" , LKML , Linux-MM , Martijn Coenen , syzkaller-bugs , Todd Kjos , Markus Elfring Subject: Re: possible deadlock in shmem_fallocate (4) Message-ID: <20200715063639.GA5451@dhcp22.suse.cz> References: <0000000000000b5f9d059aa2037f@google.com> <20200714033252.8748-1-hdanton@sina.com> <20200714053205.15240-1-hdanton@sina.com> <20200714140859.15156-1-hdanton@sina.com> <20200714141815.GP24642@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue 14-07-20 10:32:20, Suren Baghdasaryan wrote: [...] > I'm not sure how we can annotate the fact that the inode_lock in > generic_file_write_iter and in shmem_fallocate always operate on > different inodes. Ideas? I believe that the standard way is to use lockdep_set_class on your backing inode. But asking lockdep experts would be better than relying on my vague recollection -- Michal Hocko SUSE Labs