From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2810C3D6CDE for ; Thu, 18 Jun 2026 07:55:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781769315; cv=none; b=gC6s5qFyb+WiplkqzTKMYrvUCj4aK4DOdXWb836QcLKeI/uAAzjwKLfr+Y55quvNGxbpH7nCUMpNVewF/kWtrGLs4O0fa1pfUFcdawWcXz3kbebFxTXiyOVWOcYdO9sRSXvu/PhTUOgPyRjKAYdgiL8UuKUc3tsBqag55AdXGh0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781769315; c=relaxed/simple; bh=41pYxcdFUTdl+nRgCeyJZg6CRW6klbPHt8q5iw+IN8I=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=ImO6YveKDn1ipNHHA+yOjW5PZVNxItCKbfOuRRh1Aos1FZ/vOWyZGi8EeHHnZa1l6PyFi0StDVHdKhq/MUrjd6IDo4JAMYQaBnSChckCaU6WdSa7Kj7Xoa5nY87+oYSyYCXHZEgg3iOsBKPVYq2IXjD4Y/OG4Qilno5WCANAqUc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=hR68x+AP; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="hR68x+AP" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EC7461F000E9; Thu, 18 Jun 2026 07:55:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1781769313; bh=EkAdqSMgT4IE675E96Ud/DGR3xfZxz5Ydu1hH9Sk92I=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=hR68x+APscYPTTUaaeyVnTYO1e8f8HwElrVN+2G6wh91nB+LwsFxXXXIejmWEdWDp /l9MGTfHL/0VF3THyK+v+ac54bbE5/lIu4RBxr/g/NMKCjJm0TTBxEhHSVIuX2d8hv gpYTFyDUcAVjTIStNCVJWFT70x08K7Ueo29nH8xyG1FIBfPZ4elpycbbouH5JLA0f9 zGSwLwPQybL54Ij5H2cTM5v9c2Kq0nshQZ4bfWYZeDNH/oLuRrZNI+AKs1lu/oMC+K w3FsFRymcTRQg1xLP9J+CC8XWaEtRssmH7OEoR8NDsenQkYURPBLPhr4irtGhCxTjX dRWQSXdVcPQWA== Message-ID: Date: Thu, 18 Jun 2026 09:55:04 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 02/12] mm/rmap: Add try_to_unmap_hugetlb_one To: Lance Yang , dev.jain@arm.com Cc: akpm@linux-foundation.org, ljs@kernel.org, chrisl@kernel.org, kasong@tencent.com, hughd@google.com, liam@infradead.org, riel@surriel.com, vbabka@kernel.org, harry@kernel.org, jannh@google.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, qi.zheng@linux.dev, shakeel.butt@linux.dev, baohua@kernel.org, axelrasmussen@google.com, yuanchu@google.com, weixugc@google.com, shikemeng@huaweicloud.com, nphamcs@gmail.com, bhe@redhat.com, youngjun.park@lge.com, baolin.wang@linux.alibaba.com, pfalcato@suse.de, ryan.roberts@arm.com, anshuman.khandual@arm.com References: <20260618074449.24974-1-lance.yang@linux.dev> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit > return __rste_to_pte(pte_val(*ptep)); > } > >>> + VM_WARN_ON(!pte_present(pteval)); >>> + subpage = folio_page(folio, pte_pfn(pteval) - folio_pfn(folio)); >> >> No need for subpages. > > So plain ptep_get() can feed raw huge-entry bits into pte_pfn(), and the > derived subpage can be wrong. Good question which impact that might have in practice? -- Cheers, David