From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wj0-f197.google.com (mail-wj0-f197.google.com [209.85.210.197]) by kanga.kvack.org (Postfix) with ESMTP id 1F4996B0253 for ; Wed, 18 Jan 2017 08:17:17 -0500 (EST) Received: by mail-wj0-f197.google.com with SMTP id ez4so2433730wjd.2 for ; Wed, 18 Jan 2017 05:17:17 -0800 (PST) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id p198si20033729wmb.10.2017.01.18.05.17.15 for (version=TLS1 cipher=AES128-SHA bits=128/128); Wed, 18 Jan 2017 05:17:15 -0800 (PST) Date: Wed, 18 Jan 2017 14:17:11 +0100 From: Michal Hocko Subject: Re: [Bug 192571] zswap + zram enabled BUG Message-ID: <20170118131711.GA7021@dhcp22.suse.cz> References: <20170117122249.815342d95117c3f444acc952@linux-foundation.org> <20170118013948.GA580@jagdpanzerIV.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170118013948.GA580@jagdpanzerIV.localdomain> Sender: owner-linux-mm@kvack.org List-ID: To: Sergey Senozhatsky Cc: sss123next@list.ru, Dan Streetman , Seth Jennings , Minchan Kim , bugzilla-daemon@bugzilla.kernel.org, linux-mm@kvack.org, Andrew Morton On Wed 18-01-17 10:39:48, Sergey Senozhatsky wrote: > Cc Dan > > On (01/17/17 12:22), Andrew Morton wrote: > > > https://bugzilla.kernel.org/show_bug.cgi?id=192571 > > > > > > --- Comment #1 from Gluzskiy Alexandr --- > > > [199961.576604] ------------[ cut here ]------------ > > > [199961.577830] kernel BUG at mm/zswap.c:1108! > > zswap didn't manage to decompress the page: > > static int zswap_frontswap_load(unsigned type, pgoff_t offset, > struct page *page) > { > ... > dst = kmap_atomic(page); > tfm = *get_cpu_ptr(entry->pool->tfm); > ret = crypto_comp_decompress(tfm, src, entry->length, dst, &dlen); > put_cpu_ptr(entry->pool->tfm); > kunmap_atomic(dst); > zpool_unmap_handle(entry->pool->zpool, entry->handle); > BUG_ON(ret); > ^^^^^^^^^^^ Ugh, why do we even do that? This is not the way how to handle error situations. AFAIU propagating the error out wouldn't be a big deal because we would just fallback to regular swap, right? -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org