From nobody Mon Feb 9 14:22:38 2026 Received: from mail.loongson.cn (mail.loongson.cn [114.242.206.163]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 22329306B31 for ; Tue, 4 Nov 2025 07:30:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=114.242.206.163 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762241418; cv=none; b=OK6UhtfENJCjorKhSC++HGVm+H1Uju/ffwb0rJfefXea3HLoSACuutWRv4ZbM1tKzaLzE9FdW7X4K9FqfaXdqNSPMchFPA3yd9DIiNnfSdBu7QrWkshap+uyHxtzx5T1dddih+o6BO5b/pxNyzAorXkrk3hi0Hku3hXwqJkWwoM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762241418; c=relaxed/simple; bh=4qu48qG7YL4eZS1i6WIUe1h73DZmFPEKiZYJlND7Mn0=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=DT+1IIB1RsF4Al4hIcApUGtPHZzWWf3JWbf3MIemZ9HPSlz0ydAmy+FLPuPD8Sen6eTKuNLm8fqoeeYDBDAkiCZGmLekftmRl1ZZYeBRNcnZti9UAWTPyiQmhEH7Ob1raNoms7GniafCKAMX5uF0Glv8A/O1GDD7cFDlrDDH93g= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=loongson.cn; spf=pass smtp.mailfrom=loongson.cn; arc=none smtp.client-ip=114.242.206.163 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=loongson.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=loongson.cn Received: from loongson.cn (unknown [10.40.57.136]) by gateway (Coremail) with SMTP id _____8BxmdGDqwlpspkeAA--.1093S3; Tue, 04 Nov 2025 15:30:11 +0800 (CST) Received: from localhost.localdomain (unknown [10.40.57.136]) by front1 (Coremail) with SMTP id qMiowJAxfcGBqwlpo+MlAQ--.61910S2; Tue, 04 Nov 2025 15:30:09 +0800 (CST) From: Tianyang Zhang To: chenhuacai@kernel.org, kernel@xen0n.name, akpm@linux-foundation.org, willy@infradead.org, david@redhat.com, linmag7@gmail.com, thuth@redhat.com, maobibo@loongson.cn, apopple@nvidia.com Cc: loongarch@lists.linux.dev, linux-kernel@vger.kernel.org, Tianyang Zhang , Liupu Wang Subject: [PATCH] Loongarch:Make pte/pmd_modify can set _PAGE_MODIFIED Date: Tue, 4 Nov 2025 15:30:06 +0800 Message-ID: <20251104073006.1764241-1-zhangtianyang@loongson.cn> X-Mailer: git-send-email 2.41.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: qMiowJAxfcGBqwlpo+MlAQ--.61910S2 X-CM-SenderInfo: x2kd0wxwld05hdqjqz5rrqw2lrqou0/ X-Coremail-Antispam: 1Uk129KBj93XoW7KFWftFWkAFyxAw1xWw47KFX_yoW8Zr4UpF s7CF9Yvay5Kr1xZay3JF17Xr15AwsrGas7J3sFk3WkG3Wqq3yjqr1xKwn8Zr1rXay8Zr18 X3yFgw45WF4UJwbCm3ZEXasCq-sJn29KB7ZKAUJUUUUx529EdanIXcx71UUUUU7KY7ZEXa sCq-sGcSsGvfJ3Ic02F40EFcxC0VAKzVAqx4xG6I80ebIjqfuFe4nvWSU5nxnvy29KBjDU 0xBIdaVrnRJUUUBjb4IE77IF4wAFF20E14v26r1j6r4UM7CY07I20VC2zVCF04k26cxKx2 IYs7xG6rWj6s0DM7CIcVAFz4kK6r1Y6r17M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48v e4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_Xr0_Ar1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI 0_Gr0_Cr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_ GcCE3s1ln4kS14v26r126r1DM2AIxVAIcxkEcVAq07x20xvEncxIr21l57IF6xkI12xvs2 x26I8E6xACxx1l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r126r1D McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr4 1lc7CjxVAaw2AFwI0_JF0_Jw1l42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_ Gr1l4IxYO2xFxVAFwI0_JF0_Jw1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK67 AKxVWUGVWUWwC2zVAF1VAY17CE14v26r1q6r43MIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8I cVAFwI0_JFI_Gr1lIxAIcVC0I7IYx2IY6xkF7I0E14v26r1j6r4UMIIF0xvE42xK8VAvwI 8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v2 6r1j6r4UYxBIdaVFxhVjvjDU0xZFpf9x07j5o7tUUUUU= Content-Type: text/plain; charset="utf-8" In the current pte_modify operation, _PAGE_DIRTY might be cleared. Since the hardware-page-walk does not have a predefined _PAGE_MODIFIED flag, this could lead to loss of valid data in certain scenarios. The new modification involves checking whether the original PTE has the _PAGE_DIRTY flag. If it exists, the _PAGE_MODIFIED bit is set, ensuring that the pte_dirty interface can return accurate information. Co-developed-by: Liupu Wang Signed-off-by: Liupu Wang Signed-off-by: Tianyang Zhang --- arch/loongarch/include/asm/pgtable.h | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/arch/loongarch/include/asm/pgtable.h b/arch/loongarch/include/= asm/pgtable.h index bd128696e96d..106abfa5183b 100644 --- a/arch/loongarch/include/asm/pgtable.h +++ b/arch/loongarch/include/asm/pgtable.h @@ -424,8 +424,13 @@ static inline unsigned long pte_accessible(struct mm_s= truct *mm, pte_t a) =20 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) { - return __pte((pte_val(pte) & _PAGE_CHG_MASK) | - (pgprot_val(newprot) & ~_PAGE_CHG_MASK)); + unsigned long val =3D (pte_val(pte) & _PAGE_CHG_MASK) | + (pgprot_val(newprot) & ~_PAGE_CHG_MASK); + + if (pte_val(pte) & _PAGE_DIRTY) + val |=3D _PAGE_MODIFIED; + + return __pte(val); } =20 extern void __update_tlb(struct vm_area_struct *vma, @@ -547,9 +552,13 @@ static inline struct page *pmd_page(pmd_t pmd) =20 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot) { - pmd_val(pmd) =3D (pmd_val(pmd) & _HPAGE_CHG_MASK) | + unsigned long val =3D (pmd_val(pmd) & _HPAGE_CHG_MASK) | (pgprot_val(newprot) & ~_HPAGE_CHG_MASK); - return pmd; + + if (pmd_val(pmd) & _PAGE_DIRTY) + val |=3D _PAGE_MODIFIED; + + return __pmd(val); } =20 static inline pmd_t pmd_mkinvalid(pmd_t pmd) --=20 2.41.0