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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 40C8E106ACEF for ; Thu, 12 Mar 2026 22:42:09 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 5635F6B00C6; Thu, 12 Mar 2026 18:42:08 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 4E7866B00C8; Thu, 12 Mar 2026 18:42:08 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3E9E56B00CA; Thu, 12 Mar 2026 18:42:08 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 2A97F6B00C6 for ; Thu, 12 Mar 2026 18:42:08 -0400 (EDT) Received: from smtpin06.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id B7BCE1B7FB7 for ; Thu, 12 Mar 2026 22:42:07 +0000 (UTC) X-FDA: 84538885494.06.085DBE9 Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf29.hostedemail.com (Postfix) with ESMTP id AA7A012000F for ; Thu, 12 Mar 2026 22:42:05 +0000 (UTC) Authentication-Results: imf29.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=mdT6dHHc; spf=pass (imf29.hostedemail.com: domain of yosry@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=yosry@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1773355325; 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=lC2a+1vOmRKp3WlfoeTjd43xyQDMCZwY8VihOpOWx2k=; b=5WFi1lhL2x8QFUAuZK+ckcVYVjC8AOy5Bmga0gyUciDlPCZTwOKAYZy2cpXXaVqGu4VSeM n5ijF91z64AFnztmBIrL6lrp52R8ic0nAWjUiaHaJ6rt9MpbsZYzvGaTWdoTuu1UQNdmSE SbllSPTFHWsm3sTyIbXvMGs1xsCbqpE= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1773355325; a=rsa-sha256; cv=none; b=u80hYyG9FAbRLCo7FPJ5197ndo9hStGh/VjV9PsLXehlNNq54SAY8KR1892WPgSnsnd6Wi HzXW0pcRvY3ESBJwhc9hxPn83VBQWXomI7FOQ1cPpre7PD5cBa4N7TTrTLqKwwAPTKDLoH uIUv+vXZ8REV3cRJSTMdjoWvEl0iuBM= ARC-Authentication-Results: i=1; imf29.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=mdT6dHHc; spf=pass (imf29.hostedemail.com: domain of yosry@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=yosry@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 76B7542ABB for ; Thu, 12 Mar 2026 22:42:04 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 53CF1C19425 for ; Thu, 12 Mar 2026 22:42:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773355324; bh=HHV+jtL/hjU1db8zdC4zMLkvl9PbzMDoy2kQU0Dx+tM=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=mdT6dHHcAt6V/CpqpRZaVALOF95EOcrXXZ784JAFN/5vX8mb8wbvdAj2GsxZ6cb0F 0BXeyXrEGp74j9yFwVVyz56cXYOQKCdRNuvWoODPBUdBJFFBgJ54LMDcgtGIAW5OEP ZUv2Xuoah7em2JMErw7xsVJrtH5YFiQ2+9vFhtLrnlfjPKizcwBJCYVAQhVH8sa6Wr v1RTI9b1UFbAJdkynr9U4lvc/CMujwmDzDDomsR9GzSV/TZPnFAyfL13nC9f5nWnQD 7Dpu476sZjNOlQkt7Hk3KqMwX7zC+M1qJ6zbGPxb9ccdLsJ8x13Qyv9jf+yrC4Q/4r r2Xr5Bhn7ySeQ== Received: by mail-ej1-f51.google.com with SMTP id a640c23a62f3a-b976536806cso51778266b.0 for ; Thu, 12 Mar 2026 15:42:04 -0700 (PDT) X-Forwarded-Encrypted: i=1; AJvYcCXPtysG8uAkKq4T8ZuvpBac8TQapFyyMo1rBLww0Wr6gsLxmhxlyH9bkwISc6bAWcsdTyI3PzG20g==@kvack.org X-Gm-Message-State: AOJu0Yy5xIjs15ZBxt/hAF9S3eViDKyJzZXe8w0kJ1462jEheMhyFqem YpoKZiwjLSelFNHKdtQse19/EkBGigIWDh7SBs1/gO0aUapIL28/sLh0JiIfRNx0gD30sar5wMA te76LgActwNxUBqxYAmOfJ98G2pxcKf0= X-Received: by 2002:a17:907:94d3:b0:b94:1771:5296 with SMTP id a640c23a62f3a-b97651433b9mr58650466b.23.1773355323156; Thu, 12 Mar 2026 15:42:03 -0700 (PDT) MIME-Version: 1.0 References: <20260312040627.55257-1-liwang@redhat.com> <20260312040627.55257-2-liwang@redhat.com> In-Reply-To: <20260312040627.55257-2-liwang@redhat.com> From: Yosry Ahmed Date: Thu, 12 Mar 2026 15:41:51 -0700 X-Gmail-Original-Message-ID: X-Gm-Features: AaiRm50EiwfxZTHpWfQGcASFk7zY7F3P-3cUk_qRomA1oNgqKm5k_mkkpcGbFG8 Message-ID: Subject: Re: [PATCH v2 2/7] selftests/cgroup: avoid OOM in test_swapin_nozswap To: Li Wang Cc: mkoutny@suse.com, yosryahmed@google.com, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Johannes Weiner , Michal Hocko , Muchun Song , Nhat Pham , Tejun Heo , Roman Gushchin , Shakeel Butt Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: AA7A012000F X-Stat-Signature: o3ztkfrzn1ogors3cp7fb7qej93uoqjs X-HE-Tag: 1773355325-192478 X-HE-Meta: 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 10PkTeTf 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Mar 11, 2026 at 9:06=E2=80=AFPM Li Wang wrote: > > test_swapin_nozswap can hit OOM before reaching its assertions on some > setups. The test currently sets memory.max=3D8M and then allocates/reads > 32M with memory.zswap.max=3D0, which may over-constrain reclaim and kill > the workload process. > > Raise memory.max to 24M so the workload can make forward progress, and > lower the swap_peak expectation from 24M to 8M to keep the check robust > across environments. > > The test intent is unchanged: verify that swapping happens while zswap > remains unused when memory.zswap.max=3D0. > > =3D=3D=3D Error Logs =3D=3D=3D > > # ./test_zswap > TAP version 13 > 1..7 > ok 1 test_zswap_usage > not ok 2 test_swapin_nozswap > ... > > # dmesg > [271641.879153] test_zswap invoked oom-killer: gfp_mask=3D0xcc0(GFP_KER= NEL), order=3D0, oom_score_adj=3D0 > [271641.879168] CPU: 1 UID: 0 PID: 177372 Comm: test_zswap Kdump: loade= d Not tainted 6.12.0-211.el10.ppc64le #1 VOLUNTARY > [271641.879171] Hardware name: IBM,9009-41A POWER9 (architected) 0x4e02= 02 0xf000005 of:IBM,FW940.02 (UL940_041) hv:phyp pSeries > [271641.879173] Call Trace: > [271641.879174] [c00000037540f730] [c00000000127ec44] dump_stack_lvl+0x= 88/0xc4 (unreliable) > [271641.879184] [c00000037540f760] [c0000000005cc594] dump_header+0x5c/= 0x1e4 > [271641.879188] [c00000037540f7e0] [c0000000005cb464] oom_kill_process+= 0x324/0x3b0 > [271641.879192] [c00000037540f860] [c0000000005cbe48] out_of_memory+0x1= 18/0x420 > [271641.879196] [c00000037540f8f0] [c00000000070d8ec] mem_cgroup_out_of= _memory+0x18c/0x1b0 > [271641.879200] [c00000037540f990] [c000000000713888] try_charge_memcg+= 0x598/0x890 > [271641.879204] [c00000037540fa70] [c000000000713dbc] charge_memcg+0x5c= /0x110 > [271641.879207] [c00000037540faa0] [c0000000007159f8] __mem_cgroup_char= ge+0x48/0x120 > [271641.879211] [c00000037540fae0] [c000000000641914] alloc_anon_folio+= 0x2b4/0x5a0 > [271641.879215] [c00000037540fb60] [c000000000641d58] do_anonymous_page= +0x158/0x6b0 > [271641.879218] [c00000037540fbd0] [c000000000642f8c] __handle_mm_fault= +0x4bc/0x910 > [271641.879221] [c00000037540fcf0] [c000000000643500] handle_mm_fault+0= x120/0x3c0 > [271641.879224] [c00000037540fd40] [c00000000014bba0] ___do_page_fault+= 0x1c0/0x980 > [271641.879228] [c00000037540fdf0] [c00000000014c44c] hash__do_page_fau= lt+0x2c/0xc0 > [271641.879232] [c00000037540fe20] [c0000000001565d8] do_hash_fault+0x1= 28/0x1d0 > [271641.879236] [c00000037540fe50] [c000000000008be0] data_access_commo= n_virt+0x210/0x220 > [271641.879548] Tasks state (memory values in pages): > ... > [271641.879550] [ pid ] uid tgid total_vm rss rss_anon rss_fi= le rss_shmem pgtables_bytes swapents oom_score_adj name > [271641.879555] [ 177372] 0 177372 571 0 0 = 0 0 51200 96 0 test_zswap > [271641.879562] oom-kill:constraint=3DCONSTRAINT_MEMCG,nodemask=3D(null= ),cpuset=3D/,mems_allowed=3D0,oom_memcg=3D/no_zswap_test,task_memcg=3D/no_z= swap_test,task=3Dtest_zswap,pid=3D177372,uid=3D0 > [271641.879578] Memory cgroup out of memory: Killed process 177372 (tes= t_zswap) total-vm:36544kB, anon-rss:0kB, file-rss:0kB, shmem-rss:0kB, UID:0= pgtables:50kB oom_score_adj:0 > > Signed-off-by: Li Wang > Cc: Johannes Weiner > Cc: Michal Hocko > Cc: Michal Koutn=C3=BD > Cc: Muchun Song > Cc: Nhat Pham > Cc: Tejun Heo > Cc: Roman Gushchin > Cc: Shakeel Butt > Cc: Yosry Ahmed Acked-by: Yosry Ahmed