From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=74.125.82.50 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794333647; b=lpZbz6dd1EJD7kfoSyDiKteTDbCwF/FODJ98NYK2jCrofGdxKS2xEmbzLiMLAl4pY6e7 vJ2zBhYs5/ILZYUt+I6UF5im0Yk0FehuCDjjBFIxZhS7gEjuZLXRaB5nrWMUaQ/KHhh6j khjGz5UrFv3XTKo1fksSRaHITNTYkTy2EauRxGK3JTCrXqk98CUH8BpGI4/PZRvfa/iYa sL4UDLMcoRBJzBCcFMIBKxsB4IGRyxWFTGwWK2+v/kHUIbOa7OioFyJ7pgf75NjsNO4jd wCl+LIcL60AC51nM7vbbYh+LZ6W5Y8gF0ROBfSd3dxeTVBUDYz80BEXISK8a7rSdzSw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794333647; h=DMARC-Filter:Received:DKIM-Signature:X-Google-DKIM-Signature: X-Forwarded-Encrypted:X-Gm-Message-State:X-Gm-Gg:X-Received:Received: From:To:Cc:Subject:Date:Message-Id:X-Mailer:In-Reply-To:References: MIME-Version:Content-Transfer-Encoding; bh=+9N5Sc1Y8ONMq1nw5Y8gb9n5wSCLwY8oTDzk3ovJiVU=; b=nautuD3okE2+lmCiCHfX5W3wY9t4pHp067i9Xvq0Rbd9kTr2QtIrMqJps1hMYqAE8e56 B/OOPQ+I8i8ZhX/up4NJsi5AY/qnq+8zCxqNrDYjNFJx2jOqFF5SgSGmYOCRqbqqG4Trf qvxasJYjEW9EITLnYSM70oAXKc45lZN8UGJX7B4PfJqeEVYjF7hjlffewSaArZJbMJUva fJlWZm4WBx59Mk52OfDcaxrCaG/inZ49UMZdNcWjn0jS4ZQedl53ntxgNMpwKahw3CThL ac7qDYm14z0ghl//Ijr6pLYL+IM+nwz2nBnG/YuCHtVBj4craBx8i5JUo+SHmLiP20Q== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20260707 header.b=lPpAztYi; arc=none smtp.remote-ip=74.125.82.50 Received: from mail-dl1-f50.google.com (mail-dl1-f50.google.com [74.125.82.50]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6E13B606A330 for ; Tue, 10 Nov 2026 18:00:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 6E13B606A330 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20260707 header.b=lPpAztYi Received: by mail-dl1-f50.google.com with SMTP id a92af1059eb24-1931ff67a29so2634573c88.1 for ; Tue, 10 Nov 2026 10:00:47 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20260707; t=1794333647; x=1794938447; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to:content-type; bh=+9N5Sc1Y8ONMq1nw5Y8gb9n5wSCLwY8oTDzk3ovJiVU=; b=lPpAztYi8aeJ6OBN3RP85MvzjoYDSOhz7iAhYyUIZRsC8DPug6tPHBt/nB+KDlNTB6 +pzVynLqxFDI9e8ge35hXlobrdy/GjZuFhegfNK9bQ6sVszbr/iWI5zUNY6TQdC6Gua4 soK1gUrcxITYiPfAWjUprq4PzOOy7EcuKu1imvqGZgBf1dOGYIbo0Ns/kZMP5apTPyZ4 yCp44Gu/SIAeEMEgeeaDRpFu7fjKstGzrd1Et6syGgP0XhyjcRsX9N3/miR/oD/vvmxh bf/YEgEWIyLEGpdq7rvTWk9hbkDRFuw1+wHG2QKhxmTs968gGt9hvLfOitv/70qLpbhf UiSQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1794333647; x=1794938447; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to:content-type; bh=+9N5Sc1Y8ONMq1nw5Y8gb9n5wSCLwY8oTDzk3ovJiVU=; b=ZhPcAeMlKFkMCihQmqua5lu6vtU584v2OWWaxXqVo+9cLLL+LJ+vX3cz3TA4WuIm3J sexzb2nw/8X2hzo2vJ/F888qTtOGV851KiF4rWtFnp0+zEArwe0k+msVQrAesP9IwzEk fMNkHG2n/lYr+JTs/LX72BYSmwO9wGxBj4pj8jJzNpHoXL2HpwneEjG4EhXb2Bwd/Dhg WZr+iSbH9+z8450MQLKvsSl9R7almiQycnbPabMQoBurFWt76VRH5+f+QEW6mM6VV2SX /DZTtkukFMILXlMRe68zPOtOnst+rNO+BC83tru0H4Y3JwCJnUmeikrWk569vOHdgWMr hzcQ== X-Forwarded-Encrypted: i=1; AL+hErHJRFXwtMjY1ba9pOj65KNmwt2tDJb18KPcBBTzWiwfMz6CFLd/N9e+J4lvOuFvLgSO+Ku/5m1tvmEK4Xo=@vger.kernel.org X-Gm-Message-State: APuU4Z/1q+QDiRV8fLJHnY3YuQx2+jolKdY4SjA8PGaD9DOwZqA0ssYz 3nFGj58bu8T/NaV1PVPwvHKb0BXf541BJp679uzbOXCN8Md4pqiXZJiW X-Gm-Gg: AYBFou2ggbpr7EugHTpqboqwHbTzziqoteyAz+Pod1wDEQWkY/5AYL4orunRGxtbUnK y/ZaZVjiHKtjjjV3QfSEDAtKfHejABwcLKYtzk/h9P5zYLPvECIXIblZTHnDIpxqs8DzGI6DbPr IEYf9Y7YqEuxJXlvIBq4YjHV0b3NaJ/2o0NSlYycJ6KZhmi/twZ1BMmigyBs9nBGXkkXMr8HkFo v92cT5jWQFL9DswxltnXVAtPmChTT//ut5ohRiqQfmMlpBYnqCOiRBLujP2pjliPe71pAqNJFUF KjJI8+KlRQIuvIvwIPffwlQDjbRyvJ/PKf4edUHp3uPSROwH2K5DmeYBt1FKQCcVer9oS5aQdJI jFizaouLEw/iUKuwWfhb5Go49om329ZQ+LfzlF147LHasdbcnELKZqxrYeNpyi01sj7lVdDRQ7J hkUR30dHcbDmj7aqAqhzOZULhqF/gaoR/X0IYLnmjxYUTVQkaorlCtBJg89F/GoNXtOQY+MEOdJ fLzC5VyDj2L0BsdCl45YG9eByII017QLF0aCbtpqbB1L9tJjKtSZBnGCCz1nuZ2NOW9G/Esj/DL 0k4djsYo8yppEvbiufhbqFOAgaaiADmL2M1BW+SyqY3b0OoLlryJpCJ6BAQ= X-Received: by 2002:a05:7022:b052:20b0:1ab:fe29:5081 with SMTP id a92af1059eb24-1b3b6073e47mr5274788c88.20.1794333646393; Tue, 10 Nov 2026 10:00:46 -0800 (PST) Received: from aig-kmd-01.. ([120.133.49.20]) by smtp.gmail.com with ESMTPSA id a92af1059eb24-1b3b5b4b90csm7624260c88.14.2026.11.10.10.00.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 10 Nov 2026 10:00:45 -0800 (PST) From: Yin Tirui To: akpm@linux-foundation.org, david@kernel.org, ziy@nvidia.com Cc: ljs@kernel.org, dev.jain@arm.com, baolin.wang@linux.alibaba.com, baohua@kernel.org, lance.yang@linux.dev, ryan.roberts@arm.com, nico.pache@linux.dev, usama.arif@linux.dev, liam@infradead.org, kas@kernel.org, wangkefeng.wang@huawei.com, chenjun102@huawei.com, yintirui@gmail.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH RFC v2 5/9] mm/huge_memory: dispatch on the folio when splitting a huge PMD Date: Wed, 11 Nov 2026 01:59:20 +0800 Message-Id: <20261110175924.2945538-6-yintirui@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20261110175924.2945538-1-yintirui@gmail.com> References: <20261110175924.2945538-1-yintirui@gmail.com> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Only anonymous folios carry the anon rmap and PageAnonExclusive() state needed when rebuilding PTEs, so decide the split path from folio_test_anon() rather than vma_is_anonymous(). Treat a NULL folio as nothing to rebuild. This only changes behavior for folio/VMA mismatches, which are not produced by any in-tree path. Signed-off-by: Yin Tirui --- mm/huge_memory.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index d0ff2957e47f..dcc8cd380da2 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -3289,7 +3289,7 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, if (unlikely(!is_present && !folio)) return; - if (!vma_is_anonymous(vma)) { + if (!folio || !folio_test_anon(folio)) { unmap_huge_pmd_entry(vma, haddr, pmd, folio, is_present); return; } @@ -3299,14 +3299,12 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, entry = softleaf_from_pmd(old_pmd); page = softleaf_to_page(entry); - folio = page_folio(page); soft_dirty = pmd_swp_soft_dirty(old_pmd); uffd_wp = pmd_swp_uffd(old_pmd); write = softleaf_is_migration_write(entry); - if (PageAnon(page)) - anon_exclusive = softleaf_is_migration_read_exclusive(entry); + anon_exclusive = softleaf_is_migration_read_exclusive(entry); young = softleaf_is_migration_young(entry); dirty = softleaf_is_migration_dirty(entry); } else if (pmd_is_device_private_entry(old_pmd)) { @@ -3314,7 +3312,6 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, entry = softleaf_from_pmd(old_pmd); page = softleaf_to_page(entry); - folio = page_folio(page); soft_dirty = pmd_swp_soft_dirty(old_pmd); uffd_wp = pmd_swp_uffd(old_pmd); @@ -3366,7 +3363,6 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, */ old_pmd = pmdp_invalidate(vma, haddr, pmd); page = pmd_page(old_pmd); - folio = page_folio(page); if (pmd_dirty(old_pmd)) { dirty = true; folio_set_dirty(folio); @@ -3377,7 +3373,6 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, uffd_wp = pmd_uffd(old_pmd); VM_WARN_ON_FOLIO(!folio_ref_count(folio), folio); - VM_WARN_ON_FOLIO(!folio_test_anon(folio), folio); /* * Without "freeze", we'll simply split the PMD, propagating the -- 2.34.1