From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 4FBFF4266A4; Mon, 9 Feb 2026 19:39:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770665970; cv=none; b=DVJs60Q+O3vRROqfnxxLHJvkdkRo2xxBEiw1bK7uN5IcqYR8o+K8OUknQOQouGH1MYaqSC4+oqD4pK1SoEL5KhRfaR41poIVUovi9QnROIRrUd9HZrgNR/d2lmGMw0f5hyNhzNOdRONTcIYO0tj0v9UWEDu91xr5VSKo2pQ2bv8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770665970; c=relaxed/simple; bh=n4Kvj4wOUb0BbsPUCO8jW48A0gwM+U+LAE6RdQaRVfQ=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=VeLbgkFEX23TrO37kb0KTwVsNPT+55KPj5559SSOevr7F5A8gE4XSlnZxF29cupzDwrMLnYv38n/GG+rwJyd5XNDaRtWlu1sD8kZbBsau0A/PR173ejoOzpGkim3s48OONWY5F9Ln6pCRomHxZQc/g1KDTgRaQT5MLc+b5fZMRM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=EQ4hvmkG; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="EQ4hvmkG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CDCE3C19423; Mon, 9 Feb 2026 19:39:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1770665970; bh=n4Kvj4wOUb0BbsPUCO8jW48A0gwM+U+LAE6RdQaRVfQ=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=EQ4hvmkGWYxIwKiZ2OXd/Uxe1X+keZkxqhDigcX6xGCp+GOpciQ5vLiGCA4Jdw4SS FAfr4xM2RgYh1WbX81nymMzJGjjtSKSG4pVC6UmOJmqi7s6wtIpcBqDrJvZYPbs8t9 ssCMNwpGXtLfAzA+vzLSd3fx2itWsfERSkJ42uHXM1CMUcqccmnWkfnuLAuov3NRML 0F0kpA8ZL0S6Nq28aeeLn2jqUzCcav/cxay8nDMN7bhzHLbxXxHr68YrzdxX8sKhfQ 3C1VQxugmdsOLV9wi4ubWP/IwPlGTCZw5FKr1JClym4lNwyx4hqYP89arMAXTUB/0N GNnCEWeRgMing== Message-ID: <4a759288-baf9-4fe6-9d16-034edf6615f0@kernel.org> Date: Mon, 9 Feb 2026 20:39:22 +0100 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 v3] mm/page_alloc: clear page->private in free_pages_prepare() To: Zi Yan Cc: Mikhail Gavrilov , linux-mm@kvack.org, akpm@linux-foundation.org, vbabka@suse.cz, surenb@google.com, mhocko@suse.com, jackmanb@google.com, hannes@cmpxchg.org, npiggin@gmail.com, linux-kernel@vger.kernel.org, kasong@tencent.com, hughd@google.com, chrisl@kernel.org, ryncsn@gmail.com, stable@vger.kernel.org, willy@infradead.org References: <209207FE-D3A9-4BE2-8DA7-9BE38A19F387@nvidia.com> <20260207173615.146159-1-mikhail.v.gavrilov@gmail.com> <0BC1D792-80CA-4E60-AEA0-187F73BD4723@nvidia.com> <22431471-b569-4ade-9881-387debada00b@kernel.org> <91F2E741-5473-4D34-ADA1-C9E6EDCBF5E0@nvidia.com> <546b200d-5b70-4db4-99f1-f50f6a343c10@kernel.org> <3E055DAD-647A-456B-9230-4DD2574D4E8E@nvidia.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 2/9/26 18:44, Zi Yan wrote: > On 9 Feb 2026, at 12:36, David Hildenbrand (Arm) wrote: > >> On 2/9/26 17:33, Zi Yan wrote: >>> >>> >>> I agree. Silently fixing non zero ->private just moves the work/responsibility >>> from users to core mm. They could do better. :) >>> >>> We can have a patch or multiple patches to fix users do not zero ->private >>> when freeing a page and add the patch below. >> >> Do we know roughly which ones don't zero it out? > > So far based on [1], I found: > > 1. shmem_swapin_folio() in mm/shmem.c does not zero ->swap.val (overlapping > with private); > 2. __free_slab() in mm/slub.c does not zero ->inuse, ->objects, ->frozen > (overlapping with private). > > Mikhail found ttm_pool_unmap_and_free() in drivers/gpu/drm/ttm/ttm_pool.c > does not zero ->private, which stores page order. > Looks doable then :) Should we take v3 as a quick fix to backport then? -- Cheers, David