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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4C6B7C41513 for ; Thu, 10 Aug 2023 23:16:39 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id D4E0E6B0071; Thu, 10 Aug 2023 19:16:38 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id CFEC96B0072; Thu, 10 Aug 2023 19:16:38 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BC61F6B0074; Thu, 10 Aug 2023 19:16:38 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id AE6136B0071 for ; Thu, 10 Aug 2023 19:16:38 -0400 (EDT) Received: from smtpin22.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 40936B26D6 for ; Thu, 10 Aug 2023 23:16:38 +0000 (UTC) X-FDA: 81109756476.22.04ED338 Received: from mail-lf1-f43.google.com (mail-lf1-f43.google.com [209.85.167.43]) by imf13.hostedemail.com (Postfix) with ESMTP id 8356E2001F for ; Thu, 10 Aug 2023 23:16:36 +0000 (UTC) Authentication-Results: imf13.hostedemail.com; dkim=pass header.d=google.com header.s=20221208 header.b=iP8bvxcW; dmarc=pass (policy=reject) header.from=google.com; spf=pass (imf13.hostedemail.com: domain of yosryahmed@google.com designates 209.85.167.43 as permitted sender) smtp.mailfrom=yosryahmed@google.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1691709396; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=5rGQ9Py9pERUpRDN5xhuNohTgelLDMrFaS27ePXSIqI=; b=tROTetCoWDDNOK8Ys33z9cJov9Ow793fKAVBREyrIu7lLjjvfN2iF5jNqkBW0njgEU/S8n 4VH34/w56i8Zna4Cj+TH+0oSxBU38K4zGfM/KWYvdFcsK7XID3rCCROXMPLuqe4YiCaI6x l9x6UysskY1hgZ5giRKw1S92QE2PZBo= ARC-Authentication-Results: i=1; imf13.hostedemail.com; dkim=pass header.d=google.com header.s=20221208 header.b=iP8bvxcW; dmarc=pass (policy=reject) header.from=google.com; spf=pass (imf13.hostedemail.com: domain of yosryahmed@google.com designates 209.85.167.43 as permitted sender) smtp.mailfrom=yosryahmed@google.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1691709396; a=rsa-sha256; cv=none; b=ISsWloVq3tZFPmPHmvs27qH75/DjnJ4qq2hrHep2PT5UaiDOJfnf90YWyMlCI/Up0cCJn/ gvGnybr1qMnsyAP549fjuNnjbNx19vPvUGTzVwTEocCOlSo9zSnm9AMt0ZWKeg24jLpXRg D68v1LFMz3bA8y41RJHOEw2r/JRE0M4= Received: by mail-lf1-f43.google.com with SMTP id 2adb3069b0e04-4fe457ec6e7so2264147e87.3 for ; Thu, 10 Aug 2023 16:16:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1691709394; x=1692314194; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=5rGQ9Py9pERUpRDN5xhuNohTgelLDMrFaS27ePXSIqI=; b=iP8bvxcWSy2WRDc/fthlBMuD16N9seuxTX4Y74WxV0dFrOrrvdRXnNVB4lyhCOJ+K2 ckI8CtZxMa/RGi5VilvfHHXO2mzTidTwZgcep5H4k3Oyd9FkCBFTUPnnxAGTWZY1ooA3 BHX2nrbfOyq/OaqnSyJ4La4rjXA/w/yK8cclIgWfHBxsO/JR3CyOMrJS+BQX0Y56dlrc eM1qprw+UQFxSvyZB+uAM7lz8n/7nXk5Svnc23zqRx/wqZ6+ZjOw2IQR/7giir6JxtUz XnQNCD8u7pUkKwA8DLqAZGtjWZVqSMWhcdLRQvoiBdKSxnkwMtuKNogZA3vx2iJChL3J +zDQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1691709394; x=1692314194; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=5rGQ9Py9pERUpRDN5xhuNohTgelLDMrFaS27ePXSIqI=; b=QdVACkxcZRZMXLFnmOokZzwOI6dDLsszluy7OUuR2Cw2++lu6bd1Bbc1CLO5pn6DTR k0A7qZveRplAfyiVR3IaROpYCpjHBc3fLbuuNcooNgXoHKrycZACvT4DZ81HvxbFMDKv eVvk+WH2cnmqLFuekEK31EQTVFDzCmE5X5Co7Yxb70Vfh2RTV+icP8WoO+sdjXJOWomR dmrAX4HdK23CFyToRY6j45TfKga+PMU5bGbaMmXLKZ+gOy/YzfgWirZ9+h0sraCSsSoD pMJSV20lDaFjmtfuzb6SFSPlxHbjxGQ9dCn7NFwSymXVk1qGF4u7MltC2t72gIgt6Cp1 2v5Q== X-Gm-Message-State: AOJu0YxTCPHrwAY7muv2BPGEqgbKMB6SE4kxhC1JVL3RKneVnaNkqzW8 mPThPV8P+tqckpktiZtjSRWesXdyb5CzNxCG7nagpg== X-Google-Smtp-Source: AGHT+IGNK4uyE/Tr8yc4HFri/kdX48VsivQD+lAEPIYM7KRgcSjILo0I7ai2sDqt9GcQcGZQuIJH8PJ5jFQAvgrXpQA= X-Received: by 2002:a05:6512:308e:b0:4fe:5fc:9c4b with SMTP id z14-20020a056512308e00b004fe05fc9c4bmr113879lfd.15.1691709394136; Thu, 10 Aug 2023 16:16:34 -0700 (PDT) MIME-Version: 1.0 References: <20230810095652.3905184-1-fengwei.yin@intel.com> <26949c92-95a0-414f-918a-8b8cc11e3e9c@intel.com> In-Reply-To: <26949c92-95a0-414f-918a-8b8cc11e3e9c@intel.com> From: Yosry Ahmed Date: Thu, 10 Aug 2023 16:15:57 -0700 Message-ID: Subject: Re: [PATCH] zswap: don't warn if none swapcache folio is passed to zswap_load To: "Yin, Fengwei" Cc: Yu Zhao , linux-kernel@vger.kernel.org, linux-mm@kvack.org, akpm@linux-foundation.org, willy@infradead.org, hannes@cmpxchg.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: 8356E2001F X-Rspam-User: X-Rspamd-Server: rspam02 X-Stat-Signature: shx5p6fpyqy5z3mmwepktthkh416tnkt X-HE-Tag: 1691709396-929193 X-HE-Meta: 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 E6h4up3X +PH24ZtHobNzVwEpWTvJxsoDy1jVjJs7bqDluFjeMsy9did8X6H/Yc8eeFa8NcifaiN7UScyH6DJ7ywZmuUNGP1ae5SAaoObTlQC7G5t7/lj3iRWAYxsLvwa3mzggVO8B7Gf08eUyMCl0QQIo1JFWJVj+SlBwdkCrhFhVxLFF5NBIKcBZXkAhKmoTMnlyhcG1IbeAnD4xNNJrCnPyR74fz3+X+Of+OQIoJhFVUeN+sRTJ96g/rxc8Uy8DS/CeaE+K4NGFBB5YIpUzBjLwNwwyE7Quo0lP50lohDp7iy5CuvHYN/Q= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Aug 10, 2023 at 4:09=E2=80=AFPM Yin, Fengwei wrote: > > > > On 8/11/2023 2:44 AM, Yu Zhao wrote: > > On Thu, Aug 10, 2023 at 3:58=E2=80=AFAM Yin Fengwei wrote: > >> > >> With mm-unstable branch, if trigger swap activity and it's possible > >> see following warning: > >> [ 178.093511][ T651] WARNING: CPU: 2 PID: 651 at mm/zswap.c:1387 zsw= ap_load+0x67/0x570 > >> [ 178.095155][ T651] Modules linked in: > >> [ 178.096103][ T651] CPU: 2 PID: 651 Comm: gmain Not tainted 6.5.0-r= c4-00492-gad3232df3e41 #148 > >> [ 178.098372][ T651] Hardware name: QEMU Standard PC (i440FX + PIIX,= 1996), BIOS 1.14.0-2 04/01/2014 > >> [ 178.101114][ T651] RIP: 0010:zswap_load+0x67/0x570 > >> [ 178.102359][ T651] Code: a0 78 4b 85 e8 ea db ff ff 48 8b 00 a8 01= 0f 84 84 04 00 00 48 89 df e8 d7 db ff ff 48 8b 00 a9 00 00 08 00 0f 85 c4 > >> [ 178.106376][ T651] RSP: 0018:ffffc900011b3760 EFLAGS: 00010246 > >> [ 178.107675][ T651] RAX: 0017ffffc0080001 RBX: ffffea0004a991c0 RCX= :ffffc900011b37dc > >> [ 178.109242][ T651] RDX: 0000000000000000 RSI: 0000000000000001 RDI= :ffffea0004a991c0 > >> [ 178.110916][ T651] RBP: ffffea0004a991c0 R08: 0000000000000243 R09= :00000000c9a1aafc > >> [ 178.112377][ T651] R10: 00000000c9657db3 R11: 000000003c9657db R12= :0000000000014b9c > >> [ 178.113698][ T651] R13: ffff88813501e710 R14: ffff88810d591000 R15= :0000000000000000 > >> [ 178.115008][ T651] FS: 00007fb21a9ff700(0000) GS:ffff88813bc80000= (0000) knlGS:0000000000000000 > >> [ 178.116423][ T651] CS: 0010 DS: 0000 ES: 0000 CR0: 00000000800500= 33 > >> [ 178.117421][ T651] CR2: 00005632cbfc81f6 CR3: 0000000131450002 CR4= :0000000000370ee0 > >> [ 178.118683][ T651] DR0: 0000000000000000 DR1: 0000000000000000 DR2= :0000000000000000 > >> [ 178.119894][ T651] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7= :0000000000000400 > >> [ 178.121087][ T651] Call Trace: > >> [ 178.121654][ T651] > >> [ 178.122109][ T651] ? zswap_load+0x67/0x570 > >> [ 178.122658][ T651] ? __warn+0x81/0x170 > >> [ 178.123119][ T651] ? zswap_load+0x67/0x570 > >> [ 178.123608][ T651] ? report_bug+0x167/0x190 > >> [ 178.124150][ T651] ? handle_bug+0x3c/0x70 > >> [ 178.124615][ T651] ? exc_invalid_op+0x13/0x60 > >> [ 178.125192][ T651] ? asm_exc_invalid_op+0x16/0x20 > >> [ 178.125753][ T651] ? zswap_load+0x67/0x570 > >> [ 178.126231][ T651] ? lock_acquire+0xbb/0x290 > >> [ 178.126745][ T651] ? folio_add_lru+0x40/0x1c0 > >> [ 178.127261][ T651] ? find_held_lock+0x2b/0x80 > >> [ 178.127776][ T651] swap_readpage+0xc7/0x5c0 > >> [ 178.128273][ T651] do_swap_page+0x86d/0xf50 > >> [ 178.128770][ T651] ? __pte_offset_map+0x3e/0x290 > >> [ 178.129321][ T651] ? __pte_offset_map+0x1c4/0x290 > >> [ 178.129883][ T651] __handle_mm_fault+0x6ad/0xca0 > >> [ 178.130419][ T651] handle_mm_fault+0x18b/0x410 > >> [ 178.130992][ T651] do_user_addr_fault+0x1f1/0x820 > >> [ 178.132076][ T651] exc_page_fault+0x63/0x1a0 > >> [ 178.132599][ T651] asm_exc_page_fault+0x22/0x30 > >> > >> It's possible that swap_readpage() is called with none swapcache folio > >> in do_swap_page() and trigger this warning. So we shouldn't assume > >> zswap_load() always takes swapcache folio. > > > > Did you use a bdev with QUEUE_FLAG_SYNCHRONOUS? Otherwise it sounds > > like a bug to me. > I hit this warning with zram which has QUEUE_FLAG_SYNCHRONOUS set. Thanks= . Does it make sense to keep the warning and instead change it to check SWP_SYNCHRONOUS_IO as well? Something like: VM_WARN_ON_ONCE(!folio_test_swapcache(folio) && !swap_type_to_swap_info(type)->flags && SWP_SYNCHRONOUS_IO); Of course this is too ugly, so perhaps we want a helper to check if a swapfile is synchronous. > > > Regards > Yin, Fengwei > >