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=-0.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 30FF4C64E8A for ; Thu, 3 Dec 2020 11:04:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CA13621D91 for ; Thu, 3 Dec 2020 11:04:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388903AbgLCLEq (ORCPT ); Thu, 3 Dec 2020 06:04:46 -0500 Received: from mout.gmx.net ([212.227.17.22]:49371 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388620AbgLCLEp (ORCPT ); Thu, 3 Dec 2020 06:04:45 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1606993392; bh=9+nbOrXwLJSC+W7DSVLzLP7U34ixrGEowGrDbS6eeWE=; h=X-UI-Sender-Class:Subject:From:To:Cc:Date:In-Reply-To:References; b=imnJRMJ/fhLqoVSSUsrAhzoOYA6obamY1b35vU4yq9sp8ssnEKzy/dWZyaXIrnGW0 8ush9hLlX+H01QuXoK/AKlLOnK+BTMnLSzkRD3wteEvzdrywvMGpXkOrjJOmwG4IgO /7xrc5VhfIL7NNxpjLHi/99zu9FzCNnPtR0gNjdA= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from homer.fritz.box ([185.221.149.242]) by mail.gmx.com (mrgmx105 [212.227.17.168]) with ESMTPSA (Nemesis) id 1MSKy8-1kZkoS0Fg0-00SeJo; Thu, 03 Dec 2020 12:03:12 +0100 Message-ID: <2b297170dbf98b36526f876650a2707e59d4ae92.camel@gmx.de> Subject: Re: zswap explosion when using zsmalloc pool compression From: Mike Galbraith To: Sebastian Andrzej Siewior Cc: RT Date: Thu, 03 Dec 2020 12:03:11 +0100 In-Reply-To: <20201203094805.dhk3f7mlth3vm6ck@linutronix.de> References: <20201130132014.mlvxeyiub3fpwyw7@linutronix.de> <856b5cc2a3d4eb673743b52956bf1e60dcdf87a1.camel@gmx.de> <20201130145229.mhbkrfuvyctniaxi@linutronix.de> <05121515e73891ceb9e5caf64b6111fc8ff43fab.camel@gmx.de> <20201130160327.ov32m4rapk4h432a@linutronix.de> <20201202220826.5chy56mbgvrwmg3d@linutronix.de> <64ab382309c41ca5c7a601fc3efbb6d2a6e68602.camel@gmx.de> <345fdb33f5bc0046b80c6319e61e9ee33b83cac6.camel@gmx.de> <20201203094805.dhk3f7mlth3vm6ck@linutronix.de> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.34.4 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:wzf2ux7iY1baGuh3o5iJNxQREK76XgF/MeG1sqVJ1QAFayzMScC MuJJ5ZIl+YR7k/hjB+LOqwR0iYAiyiy7BzlwL8HD7Q4oL2jIMQ965JKeGM1DiO+On00x0l1 9ihdZ6ShM5ad1avmTGEYRyuCaoqrcvntvtfjzppAQkyvi1qqXgmMA+nWK1o/2ddsHldRyQ7 kMchudJjpVtzxVAsaLftQ== X-UI-Out-Filterresults: notjunk:1;V03:K0:r3X0u48/svY=:q7oTRAYFbRjT+taH5b+1C1 PG3L21z4Capi6LLD6+4ifPopCUyJANCA8m9z2sETCiNdo+hYoMjfDP1bGHr3p0p9Tge4WwLPj 9v0RqBr6wdBQgRr1LqvkZfLVx8TyJ03aynHpnsezhuZLtSbWVymnA5cquK+NijsEvGgotYSDx 17HGAFBLAsfgLhYvcHgVwrfJq2Y4PYEOymGrTLhb9grFQt1J168UpH/oNHmjJ598z2w0J+IJy ZOTglabcQwZMQblSt62B426PlOreH36lkwPkj06x/zzvzinSNLbck5HRGp2wVFG31fOaOX9AH 9Dw91Yck5U4q6xwuoNkqencrKcuh+aaS55E3qEJ647FPmDrN1poKn2ZJBB5B53hbe4dEYCfYj RU0hPAGowG0vgT7GXgwMROzK2wNAhanjEeWCBhj4pIwI+3Rl/IDjeibIgunc+Dz1HiZDI54pU ERqX8GOB494/VLxd6/us80bKrkH8JRp8t6xw+HJie0lbujm9668T4qGaHgI8nlL44Nk60+FPl K7BrRDWosQpNcnwdJVak7DWaHro2EhpWq17EMQUsX1dKUOtTonSGameOoZXZgj+5lR2Huk5p2 /mNcaJY2XuyLV8SB1rx38M7BomaLdpaQJbxi39Kxa356JmYiNRbNNTi1R/pr7CCk8Kumq9e0w SjGv9GPoGdgP9n64Xa3YW8fJ7nlyR3Ew04ijttEanrxQu9QYLlXVcvfk41bVWnPTahtuZxi3k hI7NvcdNB/nIT9S9JmVIxlXZI8ZEHNegiLZUDUSeGf8YXJeQJSwD0QhNmMiYKgpZSYEEeTcyL jsDm/WEN60DVGXYPd2UnuLRFdLg11UFBIZEC4cpo6pNweNV5FAWxaiwLNfDsj5iZ3RhTnLRiV dD0Cy33pkzDoJJO/LJfQ== Precedence: bulk List-ID: X-Mailing-List: linux-rt-users@vger.kernel.org On Thu, 2020-12-03 at 10:48 +0100, Sebastian Andrzej Siewior wrote: > On 2020-12-03 10:40:16 [+0100], Mike Galbraith wrote: > > In thread "scheduling while atomic in z3fold", I mentioned that of the > > three pool methods, only zbud did not explode. Below is the explosion > > encountered when zsmalloc is used in conjunction with runltp -f mm. A= s > > with the z3fold explosion, this one also seems to be highly repeatable= , > > this from one of my full distro "my box plays russian dolls [1]" KVMs. > > great. > > > [ 5763.720268] kernel BUG at kernel/locking/rtmutex.c:1057! > =E2=80=A6 > > [ 5763.726016] RAX: 00000000ffffffdd RBX: ffff903f77c68080 RCX: 000000= 0000000001 > > That is a deadlock. Does lockdep say anything or does it disable the bug > from happening? The later, for the first time it did not explode. However... [ 458.195604] BUG: spinlock bad magic on CPU#1, oom01/9449 [ 458.195609] lock: 0xffff980db7c69560, .magic: 00000000, .owner: = /-1, .owner_cpu: 0 [ 458.195613] CPU: 1 PID: 9449 Comm: oom01 Kdump: loaded Tainted: G = E 5.9.12-rt20-rt #19 [ 458.195615] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS= rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014 [ 458.195616] Call Trace: [ 458.195617] dump_stack+0x77/0x97 [ 458.195633] do_raw_spin_lock+0x71/0xc0 [ 458.195644] _raw_spin_lock_irqsave+0x45/0x50 [ 458.195650] ? rt_spin_lock_slowlock+0x3a/0x70 [ 458.195652] rt_spin_lock_slowlock+0x3a/0x70 [ 458.195656] rt_spin_lock+0x46/0xc0 [ 458.195658] ? zswap_frontswap_store+0x26e/0xa50 [ 458.195665] zswap_frontswap_store+0x26e/0xa50 [ 458.195667] ? rt_mutex_futex_unlock+0x56/0x80 [ 458.195668] __frontswap_store+0x6e/0x100 [ 458.195670] swap_writepage+0x37/0x70 [ 458.195671] shmem_writepage+0x267/0x400 [ 458.195674] pageout+0xd2/0x400 [ 458.195677] shrink_page_list+0xa6e/0xbd0 [ 458.195679] shrink_inactive_list+0x216/0x620 [ 458.195683] shrink_lruvec+0x39f/0x5e0 [ 458.195689] ? shrink_node+0x237/0x6e0 [ 458.195694] shrink_node+0x237/0x6e0 [ 458.195697] do_try_to_free_pages+0xb9/0x400 [ 458.195698] try_to_free_pages+0xe6/0x3b0 [ 458.195701] __alloc_pages_slowpath.constprop.108+0x3f8/0x1090 [ 458.195705] __alloc_pages_nodemask+0x3f6/0x480 [ 458.195707] alloc_pages_vma+0x135/0x190 [ 458.195711] handle_mm_fault+0x87c/0x16f0 [ 458.195715] ? lockdep_hardirqs_on+0x79/0x100 [ 458.195718] exc_page_fault+0x343/0x720 [ 458.195720] ? asm_exc_page_fault+0x1e/0x30 [ 458.195722] ? asm_exc_page_fault+0x8/0x30 [ 458.195723] asm_exc_page_fault+0x1e/0x30 [ 458.195724] RIP: 0033:0x414300 [ 458.195726] Code: e8 d5 f5 fe ff 48 83 f8 ff 0f 84 9c 00 00 00 41 83 fd= 02 48 89 c5 74 32 41 83 fd 03 74 74 49 63 c4 48 89 ea 66 0f 1f 44 00 00 <= c6> 02 07 48 01 c2 48 89 d1 48 29 e9 48 39 cb 7f ef 31 c0 48 83 c4 [ 458.195730] RSP: 002b:00007f1e1d790ec0 EFLAGS: 00010206 [ 458.195731] RAX: 0000000000001000 RBX: 00000000c0000000 RCX: 0000000041= 6a8000 [ 458.195731] RDX: 00007f1cdde38000 RSI: 00000000c0000000 RDI: 0000000000= 000000 [ 458.195732] RBP: 00007f1c9c790000 R08: ffffffffffffffff R09: 0000000000= 000000 [ 458.195732] R10: 0000000000000022 R11: 0000000000000246 R12: 0000000000= 001000 [ 458.195733] R13: 0000000000000001 R14: 0000000000000001 R15: 00007ffe1f= 97c860