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 E24ADC44536 for ; Thu, 23 Jul 2026 00:43:02 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C1EEC6B00B8; Wed, 22 Jul 2026 20:43:01 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id BF7696B00DB; Wed, 22 Jul 2026 20:43:01 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B371E6B00DC; Wed, 22 Jul 2026 20:43:01 -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 871176B00B8 for ; Wed, 22 Jul 2026 20:43:01 -0400 (EDT) Received: from smtpin24.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay03.hostedemail.com (Postfix) with ESMTP id 0839FA0348 for ; Thu, 23 Jul 2026 00:43:01 +0000 (UTC) X-FDA: 85018191762.24.A621046 Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf16.hostedemail.com (Postfix) with ESMTP id 669E6180004 for ; Thu, 23 Jul 2026 00:42:59 +0000 (UTC) Authentication-Results: imf16.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=mTqLo440; spf=pass (imf16.hostedemail.com: domain of sj@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=sj@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=1784767379; 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-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=X+2kLP9EImJrEMVLvA4gKSuudUGJH4mKmiOkjQNmRDQ=; b=CgSdARMVGMiKhikLKQ60AIWRSt4y402HR2Qf8Er1vXy4g0vsqsL+PTWK8j1Q1JC6qOioaw CKuqDdA2OMbAup/qrxaWgKO3HjGbevsR0wzsRqEkVmIWl93av88q2ymVOAKc0x7mXCN92W bW6/6pKe8RzixXKlhINusvksLAmoWpI= ARC-Authentication-Results: i=1; imf16.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=mTqLo440; spf=pass (imf16.hostedemail.com: domain of sj@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=sj@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1784767379; b=MQfWqiLsLmb9qrOIx2JpKZ/VJx5Xmn2UM8DrB+9+uVPpQo3SUCySNHOKrFTRRJ6Oth2uc9 1u4BUykTzqkm8yXzfmujdJxxQYef0z+XUOgws15P9suGoNWK31JUXEm3cURX6wZskmY+sF OFFVBUKK7LycChOLTXdpSg3dwB8xycQ= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 9B65040750; Thu, 23 Jul 2026 00:42:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 214441F000E9; Thu, 23 Jul 2026 00:42:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784767378; bh=X+2kLP9EImJrEMVLvA4gKSuudUGJH4mKmiOkjQNmRDQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=mTqLo440Dol06r7eUsxr2uCFOzX9K0M4cgRa7uukdEBjKRDQ1wLsKCtZ7f8Qq5wfr HEg+AXOec3M7KXRZxVN9SKxvtbIk0WfaR0noRnTw/eqSsPwHG5II8/naBxyoXSNp5p NGFGcBRNvWCH9UCi8+TE5LCkI6zRdsgUqzKE5nQG2SAKeKf8nWD3KyfQAtysmY0Hoj uHeWSoorIJhn0fv4a11Rkg5mZPJQ3EB+tWLgzAXQnzXblk8qtrNhYswkU1D5Et1Qth sOML6nJjjMcByq0+E0MEjNfXZQMUAoRFBGB/ms+lKBSEAcTt7IgLJePqhrPgswMW+d HB8FaUiy05MyA== From: SJ Park To: "Lorenzo Stoakes (ARM)" Cc: SJ Park , jiale yao <19888972804@163.com>, Andrew Morton , David Hildenbrand , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/page_idle: call folio_test_lru() after folio_get() Date: Wed, 22 Jul 2026 17:42:49 -0700 Message-ID: <20260723004250.96509-1-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspam-User: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 669E6180004 X-Stat-Signature: 4gnwrbkkb1b7pgr79fi6itt4zb369pgn X-HE-Tag: 1784767379-414425 X-HE-Meta: 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 eLIB6aNb 8nzuC025mX52IYzuSWSNm9AAaiDZDqiaPEppOubSe5KFp03Q9Ce5y10NMndWsCxebr9nXMPz9QkbhY/NMsyoMiSFTAf1IUK/SPcJECaOhBNIBrx8VtMELPte8HiJXbIEwqZTQr5Nb3f0TgbaBmX3YcFaCD9ckXhysGfRCJygf8BwYrhT3zQDrY6K9UUOb3Y/czIKHF/Z2kFdn/IqwRWMORd0fAQY5e8xo7n5deHyzOy/gy4PsPuE4uw5K2VuAO2oZ3612PEFo031tTReAf25s0sctMirHKbL/peciRGIYvdebbhDKyPC1tCSHyla24zIo635yKtLr0g2zChk= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, 22 Jul 2026 13:50:05 +0100 "Lorenzo Stoakes (ARM)" wrote: > Nooooo :) this is not how you send patches. > > Also you should _reply_ to review comments, not just send another patch with no > reply. Comms is king. > > Also - don't respin so quick. Wait a day. > > Then send a v2, NOT in reply to anything. > > Really best way is to use b4, docs at > https://b4.docs.kernel.org/en/latest/contributor/prep.html and etc. > > But you can also do something like: > > git format-patch -v2 HEAD~1 > scripts/checkpatch.pl > scripts/get_maintainer.pl > git send-email --to="(andrew)" --cc="" > > > On Wed, Jul 22, 2026 at 07:20:20PM +0800, jiale yao wrote: > > page_idle_get_folio() speculatively calls folio_test_lru() before > > folio_try_get(). The folio can get freed and reallocated to a tail page > > in the meantime. In that case, VM_BUG_ON_PGFLAGS() in > > const_folio_flags() can be triggered. Remove the speculative call. > > > > This is a sibling-path bug: damon_get_folio() was copied from this > > function with the same flawed pattern. Commit d6b8b02a27b3 > > ("mm/damon/ops-common: call folio_test_lru() after folio_get()") fixed > > damon_get_folio(), but page_idle_get_folio() was left unfixed. I was actually thinking I should also do this, but I was again failed at managing my memory. Thank you for doing this, Jiale! > > KCSAN > > (strict mode) confirms the data race on the folio flags: > > > > BUG: KCSAN: data-race in ... / percpu_counter_add_batch > > page_idle_get_folio+0x7a/0x2d0 > > page_idle_bitmap_read+0xc9/0x220 > > > > Signed-off-by: Jiale Yao > > Reviewed-by: Lorenzo Stoakes (ARM) > > this should really be backported, so good to find the right commit to use as a Fixes: here. > > Also then add Cc: so it gets send for backporting. > > But _please_ wait a day before sending the v2 :) > > > --- > > Also in the v2 put a list of changes here (will not be included in commit msg) > with links to previous versions on lore. Assuming all the above nice suggestions from Lorenzo are accepted, Reviewed-by: SJ Park Thanks, SJ [...]